Obstetrics & Gynecological Nursing Department 2024-2023 PDF

Faculty of Nursing Zagazig university Obstetrics & gynecological Nursing Department High Technical Institute Of Nursing 2024-2023  Table of content Chapter Title...

Faculty of Nursing Zagazig university Obstetrics & gynecological Nursing Department High Technical Institute Of Nursing 2024-2023  Table of content Chapter Title Page 1 Anatomy Of female Genital tract 1 2 Physiology of menstruation 12 3 Fertilization 20 4 Physiological changes during pregnancy 28 5 Antenatal Assessment 38 6 Minor Discomforts 49 7 Preeclampsia 55 8 Gestational diabetes 65 9 Physiology of normal labor , 75 Anatomy of female pelvis 107 Anatomy of fetal skull Management of 1st stage of labor 128 Management 2nd stage of labor. Management of 3rd stage of normal labour 10 Management 4th stage of labor Postpartum adaptation 184 11 Hysterectomy 202 12 Genital organ prolapse 235 13 Infertility 241 14 Endometriosis 266 15 Pelvic inflammatory diseases 282 16 Polycystic ovarian disease 286  Anatomy & Physiology Of Female Reproductive System Define the terms listed. Identify the female external reproductive organs & functions of each organ. Identify the female internal reproductive organs & functions of each organ. Introduction - External Female Structures Collectively, the external female reproductive organs are called the Vulva. External Female Structures Clitoris. Mons Pubis. Vestibule. Labia Majora Perineum Labia Minora. 1  Mons Pubis Is rounded soft fullness of subcutaneous fatty tissue, prominence over the symphysis pubis that forms the anterior border of the external reproductive organs. It is covered with varying amounts of pubic hair. Labia Majora & Minora The labia Majora are two rounded, fleshy folds of tissue that extended from the mons pubis to the perineum. It is protect the labia minora, urinary meatus and vaginal introitus. Labia Minora It is located between the labia majora, are narrow. The lateral and anterior aspects are usually pigmented. The inner surfaces are similar to vaginal mucosa, pink and moist. Rich in vascularity. Clitoris. The term clitoris comes from a Greek word meaning key. Erectile organ. Its rich vascularity, highly sensitive to temperature, touch, and pressure sensation Vestibule. Is oval-shaped area formed between the labia minora, clitoris, and fourchette. Vestibule contains the external urethral meatus, vaginal introitus, and Bartholins glands. Bartholin’s Glands Two small glands on either side of the vaginal opening that provide lubrication during sexual arousal. 2  This prevents pain for the female during sexual intercourse. Perineum Is the most posterior part of the external female reproductive organs. It extends from fourchette anteriorly to the anus posteriorly. Composed of fibrous and muscular tissues that support pelvic structures. Internal Female Structures Vagina Uterus Fallopian tubes Ovaries 3 4  Fallopian tubes (Oviduct) The two tubes extended from the cornu of the uterus to the ovary. It runs in the upper free border of the broad ligament. Length 8 to 14 cm average 10 cm Its divided into 4 parts.  The ovum is pushed through the tube by cilia and muscle contractions.  This is the site of fertilization if sperm is present as the egg moves through the tube.  It takes 4-7 days after fertilization for the zygote (fertilized egg) to reach the uterus. An unfertilized ovum will degenerate. Interstitial part Which runs into uterine cavity, passes through the myometrium between the fundus and body of the uterus. About 1-2cm in length. Isthmus Which is the narrow part of the tube adjacent to the uterus. Straight and cord like, about 2 – 3 cm in length. 5  Ampulla Which is the wider part about 5 cm in length. Fertilization occurs in the ampulla. Infundibulum It is funnel or trumpet shaped. Fimbriae are fingerlike processes, one of these is longer than the other and adherent to the ovary. The fimbriae become swollen almost erectile at ovulation. Functions of fallopian tubes Gamete transport (ovum pickup, ovum transport, sperm transport). Final maturation of gamete post ovulate oocyte maturation, sperm capicitation. Fluid environment for early embryonic development. Transport of fertilized and unfertilized ovum to the uterus. 5-Fimbriae These fingerlike projections are at the end of the fallopian tubes. They will move to create a current drawing the released ovum into the fallopian tube. Ovaries Oval solid structure, 1.5 cm in thickness, 2.5 cm in width and 3.5 cm in length respectively.  Each weights about 4–8 gm. Ovary is located on each side of the uterus, below and behind the uterine tubes Structure of the ovaries Medulla Cortex 6 Hilum Ovaries and Relationship to Uterine Tube and Uterus The Medulla: The central core of the ovary surrounded by the cortex and continuous with the hilum. It is formed of connective tissue. The Cortex: The outer active part of the ovary that produces hormones and oocytes. The Hilum: Is the site of attachment of the mesovarium that carries blood vessels, nerves and lymphatics entering and leaving the ovary. Function of the ovary Secrete estrogen & progesterone. Production of ova Uterus The uterus is a hollow, pear shaped muscular organ that houses and nourishes a fertilized egg through birth.. The uterus measures about 7.5 X 5 X 2.5 cm and weight about 50 – 60 gm.  A fertilized egg will implant itself into the side of the uterus eventually creating the placenta which houses the fetus.  A uterus can grow up to 6times its normal size during pregnancy. Its normal position is anteverted (rotated forward and slightly antiflexed (flexed forward) The uterus divided into three parts Body of the uterus The upper part is the corpus, or body of the uterus The fundus is the part of the body or corpus above the area where the fallopian tubes enter the uterus. Length about 5 cm. 7  Isthmus A narrower transition zone. Is between the corpus of the uterus and cervix. During late pregnancy, the isthmus elongates and is known as the lower uterine segment. Cervix The lowermost position of the uterus “neck”. The length of the cervix is about 2.5 t0 3 cm. It will open to be about 10cm in diameter during birth. The os, is the opening in the cervix that runs between the uterus and vagina. The upper part of the cervix is marked by internal os and the lower cervix is marked by the external os. It connects the uterus to the vagina and allows sperm to enter the uterus and travels up to the fallopian tube. The cervix helps to keep the unborn baby in the body until it is ready to be born. Layers of the uterus Perimetrium. Myometrium. Endometrium. Perimetrium Is the outer peritoneal layer of serous membrane that covers most of the uterus. Laterally, the perimetrium is continuous with the broad ligaments on either side of the uterus. 8  Myometrium Is the middle layer of thick muscle. Most of the muscle fibers are concentrated in the upper uterus, and their number diminishes progressively toward the cervix. The myometrium contains three types of smooth muscle fiber 1-Longitudinal fibers (outer layer) Which are found mostly in the fundus and are designed to expel the fetus efficiently toward the pelvic outlet during birth. 2- Middle layer figure-8 fibers These fiber contract after birth to compress the blood vessels that pass between them to limit blood loss. 3- Inner layer circular fibers Which form constrictions where the fallopian tubes enter the uterus and surround the internal os Circular fibers prevent reflux of menstrual blood and tissue into the fallopian tubes. Promote normal implantation of the fertilized ovum by controlling its entry into the uterus. And retain the fetus until the appropriate time of birth. Is the inner layer of the uterus. It is responsive to the cyclic variations of estrogen and progesterone during the female reproductive cycle every month. The three layers of the endometrium are: - Compact layer - The basal layer 9 - The functional or Sponge layer this layer is shed during each menstrual period and after child birth in the lochia The Function of the uterus Menstruation --- the uterus sloughs off the endometrium. Pregnancy --- the uterus support fetus and allows the fetus to grow. Labor and birth --- the uterine muscles contract and the cervix dilates during labor to expel the fetus Vagina It is an elastic fibro-muscular tube and membranous tissue about 8 to 10 cm long. Lying between the bladder anteriorly and the rectum posteriorly. It releases menstrual fluids. Serves as a birth canal during birth. 10 The vagina is slightly acidic to prevent the growth of pathogens. The vaginal lining has multiple folds, or rugae and muscle layer. These folds allow the vagina to stretch considerably during childbirth. The reaction of the vagina is acidic, the pH is 4.5 that protects the vagina against infection. Functions of the vagina Allow discharge of the menstrual flow. Female organs of coitus. Allow passage of the fetus from the uterus. Support structures The bony pelvis support and protects the lower abdominal and internal reproductive organs. Muscle, Joints and ligaments provide added support for internal organs of the pelvis against the downward force of gravity and the increases in intra-abdominal pressure. 11  Physiology of Menstrual cycle Out line:  Introduction  Definition  Characteristics of normal menstruation  The hypothalamic-pituitary-ovarian axis  Ovarian cycle  Menstrual cycle  Menstrual abnormalities  Comfort measures during menstruation Definition:  Menstruation means cyclic uterine bleeding caused by shedding of progestational endometrium it occurs between menarche and menopause  Menstruation (also called menstrual bleeding, menses, or a period)  Shedding of the sloughed endometrium with mucous and blood through the vagina externally, following failure of fertilization or implantation  The cycle depends on changes occurring within the ovaries and fluctuation in the ovarian hormones levels, that are themselves controlled by the pituitary gland and hypothalamus (hypothalamic - pituitary – ovarian axis). NORMAL MENSTRUAL CYCLE  Mean 28 days (only 15%)  Range 21-35  3-7 days  Ovulation occur usually day 14(36 hrs after the onset of mid-cycle LH surge) Characteristics of normal menstruation 1-Menarche: 10-16 years. average 13 years. 2-Duration: 2-7 days (7 days is menorrhagia. 12 3-Amount: 30-80 ml., uses 3 napkins per day, >80 mi. is menorrhagia and < 30 ml. is hypomenorrhea. 4-Normally menstrual blood doesn't coagulate as a result of secretion of fibrinolysin enzyme (plasmin) secreted by the endometrium. 5-Menstrual molimina refers to mild symptoms of 7-10 days before menstruation relieved once menstruation occurs exaggerated condition called (premenstrual syndrome). The hypothalamic-pituitary-ovarian axis: are two main components of the menstrual cycle, the changes that happen in the ovaries in response to pituitary hormones (the ovarian cycle) and the variations that take place in the uterus, but it is important to remember that both cycles work together simultaneously to produce the menstrual cycle. menstrual cycle. During the course of a normal menstrual cycle: The ovaries go through 3 phases: 1. Follicular. 2. Ovulation. 3. Luteal. The endometrium goes through 3 phases: 1. Proliferative. 2. Secretory. 3. Menstruation. Ovarian Cycle: every month during the S reproductive life. 13  Cyclical changes in the ovaries occur in response to two anterior pituitary hormones: o Follicle-stimulating hormone(FSH) o Luteinizing hormone (LH). Ovarian follicular development  Fetus:6-7 million in 20 wks.  " At birth: 1-2 million  At puberty:300,000  " Release during ovulation: 400-500  At menopause: rare The changes that occur in the ovary during each cycle can be divided into three phases: 1. Follicular phase (day 1-13 ) 2. Ovulatory phase (day 13-15) 3. The luteal phase (day 15-28).  These phases run in parallel with the phases of the uterine cycle and together comprise the menstrual cycle  At the beginning of each menstrual cycle, the hypothalamus secretes GnRh in a pulsatile manner to stimulate ant. Pit.gland to secretes FSH & LH.  FSH is responsible for the growth of several primary follicle  The follicular phase is controlled by FSH. encompasses days 1 to 13 of a 28 day cycle.  Only one follicle on one of the ovaries reaches maturity (graafian follicle) which secretes estrogen.  Estrogen has negative feedback on the pituitary to stop FSH.  Estrogen causes the uterine lining (endometrium) to grow thicker  The estrogen peak stimulates secretion of LH. The LH peak leads to: abdominal cavity a process called (ovulation). and corpous luteum formation. 14  -day cycle. Note: High estrogen also suppress FSH secretion so no further follicles grow After ovulation, LH levels remain elevated and cause the remnants of the follicle to develop into a yellow body called the corpus luteum. estrogen, the corpus luteum secretes a hormone called progesterone. when progesterone reaches a high level it inhibits the secretion of LH leads to: Degeneration of the corpus luteum (If fertilization does not take place), "and so oestrogen and progesterone drop & separation of the endometrium (menstruation) stimulates the hypothalamus to secrete more GRH,a new cycle is started. 15  Uterine Cycle: The uterine cycle refers to the changes that are found in the uterine lining of the uterus. These changes come about in response to the ovarian hormones estrogen and progesterone. There are 4 four phases to this cycle: 1. Menstrual, 2.proliferative, 3. secretory and 4.ischemic. 1-Menstrual Phase During the menstrual phase of the uterine cycle, the uterine lining is shed because of low levels of progesterone & estrogen. At the same time, a follicle is beginning to develop and starts producing. 'The menstrual phase ends when the menstrual period stops on approximately day 5. 16  -5 days 2-Proliferative Phase o When estrogen levels are high enough, the endometrium begins to regenerate. o Estrogen stimulates blood vessels to develop. The blood vessels in turn bring nutrients and oxygen to the uterine lining and it begins to grow and become thicker. o The proliferative phase ends with ovulation on day 14. 3-Secretory Phase  After ovulation, the corpus luteum begins to produce progesterone.  This hormone causes the uterine lining to become rich in nutrients in preparation for pregnancy.  Estrogen levels also remain high so that the lining is maintained. If pregnancy doesn't occur, the corpus luteum gradually degenerates, and the woman enters the ischemic phase of the menstrual cycle. 4-Ischemic Phase  'On days 27 and 28, estrogen and progesterone levels fall because the corpus luteum is no longer producing them.  without these hormones to maintain the blood vessel network, the uterine lining becomes ischemic.  When the lining start slough, the woman has come full cycle and is once again at day 1 of the menstrual cycle. Cervical Mucus Changes: he menstrual cycle. Some women use these characteristics to help determine when ovulation is likely to happen. During the menstrual phase the cervix doesn't produce mucus. As the proliferative phase begins, the cervix begins to produce a tacky, crumbly type of mucus that is yellow or white. progressively clear, thin and lubricative, with the properties of raw egg white. At the peak of fertility (ie., during ovulation), the mucus has a 17  distensible, stretchable called spinbarkheit. After ovulation the mucus becomes scanty, thick, and opaque. Estrogen causes:  Mild mvometrial contraction  Rhythmic contraction in the fallopian tube.  Production of thin elastic mucous that attracts sperm.  In the vagina, causes cornifcation of its epithelium with increasing acidity. Progesterone causes:  Relaxation of the myometrium.  The fallopian tube epithelium to be rich with nutrients for the zygote.  Thick cervical mucous.  In the vagina decrease cornification.  In negative feedback, rising levels of hormones feedback to the hypothalamus and pituitary gland to decrease the production of the hormones.  In positive feedback, rising levels of hormones feedback to increase hormone production. 18 Care comfort measures during menstruation Menstrual hygiene: 1. Sanitary pads and tampons: 2. Wash hands before & after giving self-perineal care. 3. Washing or wiping the perineium should be always done from front to back. 4. Reduce use of tampons by substituting sanitary pads especially at night. 5. Use tampon only for heavy menstrual flow. 6. Vaginal spray and douching: 7. Spray should be used externally only not with pads. 8. Should not be applied with broken irritated or itched skin. 9. Douching washes away the natural mucus and upsets the vaginal ecology, thus make it liable to infection. CYCLE ABNORMALITIES 1. Anovulation 2. Oligomenorrhea 3. Anovulatory cycle 4. Amenorrhea 5. Hypomenorrhea 6. Polymenorrhea 7. Metrorrhagia. 19 Fertilization Pregnancy is a sequence of events that normally includes fertilization, implantation, embryonic growth, and fetal growth that terminates in birth. The first two weeks of the human development are called the pre-embryonic period. This period begins with the fertilization. Fertilization is the beginning of the pregnancy and can be considered as the beginning of a new life. Fertilization, the process by which the male and female gametes fuse, marks the beginning of the pregnancy. Female gamete (oocyte) is produced during the menstrual cycle and expelled during the ovulation. During each ovarian cycle, only one follicle with an oocyte reaches full maturity. At the 14th day in an average 28-day cycle this follicle bulges on the surface of the ovary. Immediately before the ovulation, during ovulation, follicle bursts and the oocyte is expelled into the uterine tube. The ovum is picked up by the fimbrial end of the fallopian tubes and moved towards the ampulla by the: 20 1. Ciliary movement of the cells and 2. Rhythmic peristalsis of the tube Pregnancy occurs when mature ovum is fertilized by a mature capacitated spermatozoon. To be capable of fertilization:- - Capacitation & - Acrosomal reaction Capacitation The ability of the sperm to reach & penetrate the ovum, it takes from 2-6 hours (The cervical and tubal secretions are mainly responsible for capacitation). Removal of acrosomal membrane over sperm head with activation and release of hydrolytic & proteolytic enzymes (Which are necessary for penetration of the corona radiate) After penetration of corona radiata , the sperm attaches to receptors on the zona pellucida activating acrosin (trypsin –like acrosomal enzyme), thus enables the head of the mature sperm to penetrate zona pellucida. 21 Mature ovum 1. Perivitelline space 2. Zona pellucida 3. Polar bodies 4. Sperm Poly-spermy is prevented by:  Zonal reaction Change in the action potential of ZP  Cortical reaction release of cortical granules in the peri-vitelline space. Fertilization ends with the fusion of female and male pronucleus and formation of the zygote. Within 24-48 hours after fertilization, early pregnancy factor (EPF) can be detected in the maternal serum. Zygote 1. Zygote 2. Perivitelline space 3. Zona pellucida 4. Polar bodies Cleveage After the fertilization, the zygote undergoes a series of rapid divisions called cleavage.  The zygote first divides into two cells known as blastomeres (30 hours after fertilization). Two-cell stage:- 1.Zona pellucida 2.Blastmere 22  Three days after the fertilization, a rapid increase in the number of the cells results in the formation of a solid ball of 12-16 cells, the morula. Four-cell stage morula  These repeated mitotic divisions happen during the zygote's passage through the uterine tube toward the uterus.  Morula remains 4 days in the fallopian tube & 3 days in the uterine cavity before implantation (fertilization - implantation interval is one week)  Four days after fertilization, when the morula enters the uterus, fluid-filed spaces between the blastomeres appear and fuse into a central cavity called the blastocoele. At this stage of the development, the conceptus is called a blastocyst. 23 Implantation The blastocyst usually implants on the posterior uterine wall.( 60 % post. & 40 % ant.) The implantation begins at the end of the first week and is completed by the end of the second week.  The Decidua: is the endometrium of pregnancy after fertilization (thickened & vascular). Function of Decidua Site of implantation Protection of the uterine wall against invasion by the chorionic villi. Nutrition of the embryo in the early stage 24  Implantation of the blastocyst in the endometrium of the uterus is completed during the second week of the development. The cells of the inner cell mass (embryoblast) differentiate into two layers: the hypoblast layer, consisting of small cuboidal cells, and the epiblast layer consisting of high columnar cells. The two-layered plate that will differentiate into the embryo is called the embryonic disc.  The embryo attaches to the uterine wall and penetrates first the epithelium then the circulatory system of the mother to form the placenta. 25 Placenta Anatomy at Term  Shape: discoid.  Diameter: 15-20 cm.  Weight: 500 gm.  Thickness: 2.5 cm at its center and  Gradually tapers towards the periphery. Surfaces of placenta Fetal surface: smooth, glistening and is covered by the amnion which is reflected Fetal surface on the cord. Maternal surface: dull greyish red in color and is divided into 15-20 cotyledons. Each cotyledon is formed of the branches of one main villus stem covered by decidua basalis. Function of placenta Nutrition: Substances pass from the maternal to fetal circulation Respiratory: Gas transport through the placenta by simple diffusion. Excretory: Acts as a fetal kidney Secretory Function: 26  A. Proteins: PSP & PAPP A, B and C. B. Hormones: Steroid hormones: Estrogen (E3) & progesterone. a. Protein hormones: HPL & HCG C. Enzymes Heat stable alkaline phosphatase Insulinase , mono – amine oxidase , histaminase & oxytocinase. The umbilical cord Development of the umbilical cord Origin: It develops from the connecting stalk A. At Full term, 50 cm in length and 1-2 cm in diameter. B. It consists of C.T known as Wharton jelly `covered by amnion. C. It contains 1 umbilical vein, 2 umbilical arteries. D. The umbilical vein carries oxygenated blood, while the umbilical arteries carry deoxygenated blood. E. Insertion: In the fetal surface "eccentric insertion" (70%) or "central insertion" (30%). 27 Maternal adaptation during pregnancy During pregnancy, the internal genital tract undergoes anatomical and physiological changes to accommodate the changes and development of the fetus. These changes are presented as below: Uterus  With pregnancy progression, the uterus leaves the pelvis and ascends to the abdominal cavity. The abdominal content displaced in response to the increased size of the uterus which is five times more than normal.  This increase in the size of uterus is associated with an increase of blood supply to the uterus and uterine muscle activity.  Uterus increases in size till the 38 weeks after that the fundus level starts to descend preparing for delivery. Its weight increases from 50mg to 1000mg at 40 weeks and stretches to accommodate the fetus size, which is associated with an increase in the thickness and length of the fundus. Fundus levels during pregnancy 28   In length from 6.5 to 32 cm. In depth from 2.5 to 22 cm.  In width from 4 to 24 cm In weight from 50 to 1000 grams.  In thickness of the walls from 1 to 0.5 cm Cervix  The enlarged mucus glands of the cervix during pregnancy secrete a mucus, which forms a plug called the “operculum”. This acts as a seal for the uterus and protects it from ascending infection, and acts as a barrier between the vagina and cervix.  During labor when the mucus is blood-tinged, it is referred to as a "bloody show".  The cervix undergoes a marked softening which is referred to as the Goodell's sign"  Later in pregnancy before delivery, additional changes and softening of the cervix occur prior to the beginning of labor  There is a softening of the cervix in response to oestrogen and progesterone. Ripening of the cervix occurs due to the effect of prostaglandin and relaxin as labor becomes imminent. Vagina  The muscle layer of the vagina thickens and it becomes more elastic, making it possible for the vagina to dilate during the second phase of labour. The number of squamous cells increases, due to glycogen, which predisposes the vagina towards thrush.  Increased circulation to the vagina early in pregnancy changes the color from normal light pink to a purple hue which is known as the "Chadwick's sign" 29 Ovaries.  The follicle-stimulating hormone (FSH) ceases its activity due to the increased levels of estrogen and progesterone secreted by the ovaries and corpus luteum. The FSH prevents ovulation and menstruation.  The corpus luteum enlarges during early pregnancy and may even form a cyst on the ovary. The corpus luteum produces progesterone to help maintain the lining of the endometrium in early pregnancy.  It functions until about the 10th to 12th week of pregnancy when the placenta is capable of producing adequate amounts of progesterone and estrogen. It slowly decreases in size and function after the 10th to 12th week. Changes of the skin during pregnancy Alterations in hormonal balance and mechanical stretching are responsible for several changes in the integumentary system. The following changes occur during pregnancy:  Linea Nigra. This is a dark line that runs from the umbilicus to the symphysis pubis and may extend as high as the sternum. It is a hormone induced pigmentation. After delivery, the line begins to fade, though it may not ever completely disappear. 30  Mask of pregnancy (Chloasma). This is the brownish hyper pigmentation of the skin over the face and forehead. It begins about the 16th week of pregnancy and gradually increases, then it usually fades after delivery  Striae Gravidarum (Stretch Marks). This may be due to the action of the adreno corticosteroids. It reflects a separation within underlying connective tissue of the skin. This occurs over areas of maximal stretch--the abdomen, thighs, and breasts. It will usually fade after delivery although they never completely disappear. Sweat Glands. Activity of the sweat glands throughout the body usually increases which causes the woman to perspire more profusely during pregnancy. Changes of the breast  In early pregnancy, the breast may feel full or tingle, and increase in size as pregnancy progresses. The areola of the nipples darken and the diameter increases.  The Montgomery's glands (the sebaceous glands of the areola) enlarge and tend to protrude. The surface vessels of the 31  breast may become visible due to increased circulation and turns to a bluish tint to the breasts.  By the 16th week (2nd trimester) the breasts begin to produce colostrum. This is the precursor of breast milk. It is a thin, watery, yellowish secretion that thickens as pregnancy progresses. It is extremely high in protein. Cardiovascular System The earliest and most dramatic changes in maternal physiology are cardiovascular. These changes improve fetal oxygenation and nutrition. Anatomic Changes During pregnancy, the heart is displaced upward and to the left and assumes a more horizontal position as its apex is moved laterally. These position changes are the result of diaphragmatic elevation caused by displacement of abdominal viscera by the enlarging uterus. 32 Functional Changes: The primary functional change in the cardiovascular system in pregnancy is:-  Marked increase in cardiac output: Circulating blood volume begins increasing by 6 to 8 weeks of gestation and reaches a peak increase of 45% by 32 weeks of gestation.  Systemic vascular resistance decreases because of a combination of the smooth muscle–relaxing effect.  In late pregnancy, cardiac output may decrease when venous return to the heart is impeded because of vena cava obstruction by the enlarging gravid uterus.  During labor, at the time of uterine contraction, cardiac output increases approximately 40% above that in late pregnancy.  Cardiac output increases significantly immediately after delivery, because venous return to the heart is no longer blocked by the gravid uterus impinging on the vena cava and because extracellular fluid is quickly mobilized. Respiratory System The changes that occur in the respiratory system during pregnancy are necessitated by the increased oxygen demand of the mother and fetus. These changes are primarily mediated by progesterone. Anatomic Changes :- The maternal thorax undergoes several morphologic changes due to pregnancy.  The diaphragm is elevated approximately 4 cm by late pregnancy due to the enlarging uterus. 33   Additionally, the subcostal angle widens as the chest diameter and circumference increase slightly. Functional Changes Pregnancy is associated with an increase in total body oxygen consumption of approximately 50 mL O2/minute, which is 20% greater than non-pregnant levels.  Approximately 50% of this increase is consumed by the gravid uterus and its contents, 30% by the heart and kidneys, 18% by the respiratory muscles and the remainder by the mammary tissues.  The consequence of diaphragmatic elevation is a 20% reduction in the residual volume and a 5% reduction in total lung volume.  Although the maternal respiratory rate is essentially unchanged, there is a 30% to 40% increase in tidal volume due to a 5% increase in inspiratory capacity. Hematologic System The physiologic adaptations in the maternal hematologic system maximize the oxygen- carrying capacity of the mother to enhance oxygen delivery to the fetus. 34 Anatomic Changes  The primary anatomic adaptation of the maternal hematologic system is a marked increase in plasma volume, red cell volume, and coagulation factors.  Maternal plasma volume begins to increase as early as the sixth week of pregnancy and reaches a maximum at 30 to 34 weeks of gestation, after which it stabilizes.  Red cell volume also increases during pregnancy  Because iron is actively transported to the fetus, fetal hemoglobin (Hgb) levels are maintained regardless of maternal iron stores. Supplemental iron use in pregnancy is intended to prevent iron deficiency in the mother not to prevent either iron deficiency in the fetus or to maintain maternal Hgb concentration.  The concentration of numerous clotting factors is increased during pregnancy. Fibrinogen (factor I) increases by 50%, as do fibrin split products and factors VII, VIII, IX, and X. Prothrombin (factor II)  Factors V and XII remain unchanged 35 Renal System: The renal system is the site of increased functional activity during pregnancy to maintain fluid, solute, and acid–base balance in response to the marked activity of the cardiorespiratory systems. Anatomic Changes The primary anatomic change of the renal system is enlargement and dilation of the kidneys and urinary collecting system.  The kidneys lengthen by approximately 1 cm during pregnancy.  The renal pelvis and ureters dilate during pregnancy because of mechanical and hormonal factors.  Mechanical compression of the ureters occurs as the uterus enlarges and rests on the pelvic brim. The right ureter is usually more dilated than the left, possibly due to dextrorotation of the uterus and compression from the enlarged right ovarian venous plexus. Progesterone causes relaxation of the smooth muscle of the ureters, which also results in dilation  As the uterus enlarges as pregnancy progresses, bladder capacity decreases. Functional Changes The majority of pregnancy-associated functional changes in the renal system are a result of an increase in renal plasma flow.  Early in the first trimester, renal plasma flow begins to increase, and, at term, it may be 75% greater than non-pregnant levels.  Similarly, the glomerular filtration rate (GFR) increases to 50% over the non-pregnant state. 36  Urinary glucose excretion increases in virtually all pregnant women. A trace of glucose on routine prenatal colorimetric “dipstick” evaluation is normal and is usually not associated with glycemic pathology but should be watched closely for further trends into true glycosuria.  There is no significant increase in urinary protein loss, which means that any proteinuria that occurs during pregnancy should prompt consideration of illness. In addition,  Sodium metabolism remains unchanged. The potential loss of this electrolyte caused by an increased GFR is compensated for by an increase in renal tubule reabsorption of sodium. 37  Antenatal care Objectives: By the end of the lecture, the student will be able to:  Mention the components of antenatal care.  Obtain complete history from the pregnant woman during antenatal visits.  Perform general and abdominal examination.  Auscultate FHR and identify its abnormalities.  Follow ethical issues while examining the pregnant woman. Aims of antenatal care: To screen the high risk cases To prevent or detect or treat at the earliest complication To ensure continued medical surveillance and prophylaxis To educate the mother about the physiology of pregnancy and labour by demonstrations, charts and diagrams so that fear is removed and psychology is improved To discuss with the couple about the place, time and mode of the delivery, provisionally and care of the newborn To motivate the couple about the need of family planning To advice the mother about breast-feeding, post-natal care and immunization Schedule for antenatal visits: Monthly up to 28 weeks Two weekly between 28 and 36 weeks 38  Weekly 36 weeks onwards. (This equals about 15 visits)  High-risk cases need more frequent visits Components of antenatal care: Careful antenatal assessment (history taking and examination and investigation). Advice given to the pregnant woman Antenatal assessment include: Antenatal Assessment History taking Physical Investigations examination Personal history. General examination Routine tests Present pregnancy Abdominal Optional tests history. examination Past history (medical - Inspection and surgical). - Palpation (Fundal Obstetric history height- leopold’s maneuver) Menstrual history - FHR auscultation. Family history Vaginal examination 39 History taking include:  Personal history which include: name, age, education, occupation, address, marital status and duration of marriage.  Present pregnancy history of any complaint as: nausea & vomiting, increased frequency of micturition, constipation, heaviness of breast, rise of temperature, edema, pain in the abdomen, backache and vaginal bleeding.  Past medical history: which include any medical disorder as hypertension, DM, renal, hepatic , cardiac or psychiatric disease. If the woman is taking any drugs as antihypertensives, hypoglycemics, antidepressants, corticosteroids and anticoagulants. Allergy to certain foods or drugs are also considered.  Obstetrical history which include details related to: Gravidity: number of pregnancies, any complications encountered during previous pregnancy, onset of pregnancy (spontaneous, induced or ART). Parity: number of deliveries, onset of labor (spontaneous, induced), mode of delivery( NVD or CS), GA at the onset of labor( preterm, full term or postdate), any complications encountered during labor or postpartum, sex of children. Abortion: number, GA at the onset of abortion and management techniques.  Menstrual History: age of menarche, duration of menstrual period, LMP to calculate EDD.  Family history of HTN, DM, renal, hepatic or cardiac diseases, multiple pregnancy or pregnancy complications. Physical examination:  General examination: include vital signs, breast, heart sound, lungs, appearance, height of patient, weight of patient, pallor, jaundice, edema and cyanosis. 40  Abdominal examination: Inspection of the shape of the uterus, striae gravidarum, linea nigra and scar marks. Palpation  Assessment of fundal height  Loepold’s maneuver: Fundal grip: While facing the woman, palpate the woman's upper abdomen with both hands. Often determine the size, consistency, shape, and mobility of the form that is felt. The fetal head is hard,, round, and moves independently of the trunk. The buttocks feels softer, is symmetric, and has small bony prominences; it moves with the trunk. 41 Umbalical ( Lateral grip): The maneuver attempts to determine the location of the fetal back. Facing the woman, the health care provider palpates each side of the abdomen with gentle but deep pressure using the tips of his or her hands. The fetal back is firm and smooth, hard, resistant surface. Fetal extremities feels like small irregularities and protrusions. 42 Pelvic grip: To determine which part of the fetus occupy the lower uterine segment Pawlick grip:  Done at 36 weeks to determine engagement of the fetal head.  Determine what fetal part is lying above the inlet, or lower abdomen.  The individual performing the maneuver first grasps the lower portion of the abdomen just above the symphysis pubis with the thumb and fingers of the right hand. 43 Auscultation of FHR:  Explain the procedure to the woman.  Assist the woman to a supine position.  By palpation, determine the following fetal position , fetal presentation and fetal lie  Place the head of the fetoscope on the woman’s abdomen where you are most likely to find fetal heart tones.  In cephalic presentation, FHR is auscultated below the umbilicus on the side of the fetal back.  In breech presentation, FHR is auscultated above the umbilicus on the side of the feta back.  Normal FHR is 120-160 b/m, foetal tachycardia (>160 b/m), foetal bradycardia (, consider pre-eclampsia 5. GCT 24-48 weeks --- 130 mg/dL or more, do a GTT 6- culture if infection is swabs from suspected vagina and cervix 45 Ultrasound: Benefits: Determine gestational age Detect multiple pregnancies Help with later screening for Down's syndrome. Determine the amount of amniotic fluid (average, oligohydramnios, polyhydramnios). Localize site of the placenta and evaluation of the retro placental space. Determine fetal sex. Determine fetal viability. Identify fetal presentation, position, lie and attitude. Localize fibroid with pregnancy. Diagnosis of cervical incompetence by vaginal ultrasonography. Optional tests:  Amniocentesis  Alpha fetoprotein to screen for birth defects.  Non stress test.  Screening for syphilis. In subsequent visits: Patient complains General examination Gestational age to be calculated Identification of problem 46  Foetal movement Health education Prophylaxis & treatment of anemia Developing individualized birth plan Antenatal advice: Following advices are to be given: 1- Diet should be: nutritious, balanced, light, easily digestible, rich in protein, mineral and vitamin and with woman’s choice. The woman need extra 300kcal/day from 2nd trimester onwards, Calcium : 1.5 g daily, Vit. C, folic acid, Vit. B12. 2- Rest and sleep: 8 hour sleep at night, at least 2 hour sleep after mid- day meal. Hard strenuous work should be avoided in first trimester and last 4 weeks. 3- Bowel: Regular bowel movement may be facilitated by regulation of diet, taking plenty fluid, vegetable and milk. 4- Coitus : should be avoided in 1st trimester and in the last 6 weeks. 5- Travelling: should be avoided in 1st trimester and in the last 6 weeks. Air travelling is contraindicated in placenta praevia, preeclampsia, severe anemia and history of abortion and preterm labor. Immunization: Indicated TT, HAV, HBV and Rabies. Contraindicated immunizations are live virus vaccine (rubella measles, mumps, varicella). Warning signals of pregnancy !!! Bleeding p/v at any time in pregnancy Head ache, blurring vision, epigastric pain & oliguria oedema, severe, not subsiding with rest, or on face & hands 47  Decrease/ loss of fetal movements Abdominal pain Urinary infection with vulvovaginitis Clear fluid p/v (PROM). 48  Minor Complaints During Pregnancy Objectives: By the end of the lecture, the student will be able to:  Identify several minor ailments that the woman may experience during pregnancy.  Mention the causes of each ailment or discomfort.  Determine the relief measures of each discomfort. (1) Bckache: Causes:  Lumbar lordosis.  Relaxation of ligaments and intervertebral joints by progesterone effect. Relief measures:  Adequate rest and support the back when sitting in a chair with a pillow.  Avoid wearing high heeled shoes. (2) Nausea and vomiting: It is called morning sickness.  Having vomiting and nausea and feeling tired are normal during pregnancy due to the adjustment of your body’s hormone level.  This usually all happens in early pregnancy from 4-12 wks. Relief measures:  Add dry foods like crackers, cereal and toast before waking up from the bed.  Avoid fried and fatty foods. 49   Eat small frequent meals.  In case, your vomiting is constant and severe and to have anemia test, consult your doctor. (3) Gingivitis Increased vascularity and hypertrophy of the interdental papillae. It is improved usually after pregnancy termination. Sequelae:  Increased tendency for bleeding.  Retention of food debris predisposes to sepsis and dental caries. Relief measures: Proper dental hygiene. (4) Ptyalism (Sialorrhoea) Causes: Increased salivation may occur early in pregnancy and subsides later. It is due to failure of the patient to swallow the saliva rather than increase in its amount. Relief measures:  Care of dental hygiene.  Discontinue smoking.  Anticholinergic drugs as belladonna, which induce dryness of the mouth, may be needed. (5) Heartburn Causes: A common complaint caused by reflux of gastric contents into the lower oesophagus due to mechanical relaxation of the cardiac sphincter caused by upward displacement and compression of the stomach by the pregnant uterus, and by the action of progesterone. 50 Relief measures:  More frequent but smaller meals. Avoid salty and spicy foods.  Avoidance of bending over or lying flat.  Antacids containing aluminium hydroxide are preferable as they buffer the gastric contents. (6) Constipation Causes  Reduced intestinal motility by the action of progesterone.  Increased fluid resorption from the large bowel.  Reduced exercise.  Mechanical compression by the gravid uterus. Relief measures:  Evacuate the bowel at the same time every day. Increase fluid intake.  Diet rich in green vegetables and fruits.  Mild laxative as. Liquid paraffin interferes with absorption of fat soluble vitamins, so better to be avoided. (7) Hemorrhoids Causes  Laxity of the rectal veins by progesterone effect.  Pressure by the gravid uterus.  Tendency to constipation. Relief measures:  Avoid constipation.  Soothing agents.  Local anaesthetics.  Surgical and local injection treatment have to be avoided. 51 (8) Varicosities Causes:  increased venous pressure in the lower limbs by compression with the pregnant uterus.  prolonged standing.  relaxation of veins walls by steroid hormones. Relief measures:  Avoid prolonged standing.  Encourage active exercise.  Elevate the legs in higher level than the body during sitting and sleeping.  Elastic stocking are worn while the patient is lying down and veins are empty.  Surgical or injection treatment should be avoided during pregnancy. (9) Dyspnoea: Causes:  It may occur early in pregnancy due to hyperventilation caused by progesterone.  Late in pregnancy, it occurs due to pressure on the diaphragm by the pregnant uterus. Relief measures:  Avoid tight clothes around the chest.  Sleeping in the semi- sitting position.  Well ventilated areas. 52 (10) Dependent edema Causes: Shift of fluids from the intravascular compartment to the extravascular compartment. Relief measures:  Avoid standing for long periods.  Elevate legs when laying or sitting.  Avoid tight stockings. (11) Faintness Relief measures:  Rise slowly from sitting to standing.  Evaluate hemoglobin and hematocrit.  Avoid hot environments (12) Urinary symptoms Frequency and stress incontinence may occur during pregnancy. Causes  Increased intra-abdominal pressure.  Pressure on the bladder by the enlarging uterus reducing its capacity. (13) Leucorrhoea Causes: Increased vaginal discharge is a common complaint during pregnancy due to excess oestrogen production. Relief measures: No treatment is needed except if there is associated infection. Monilial infection is common. 53 (14) Leg Cramps Sustained involuntary painful contractions, usually affecting the calf and peroneal muscles may occur in the second half of pregnancy, particularly at night. Causes  Depletion of serum calcium as well as sodium and chloride due to excessive vomiting, sweating or salt restriction.  Local vascular insufficiency. Relief measures:  Massage of the contracted muscles and passive stretching.  Calcium gluconate may be helpful. (15) Paraethesia Tingling sensation of the fingers and sometimes weakness of small muscles of the hand caused by edema of the carpal tunnel. 54 Chapter 5 Obstetrics and Gynecological Nursing Pre-eclamptic toxemia(PET) 0 Definition: Preeclampsia is a disorder of widespread vascular endothelial malfunction and vasospasm that occurs after 20 weeks' gestation and can present as late as 4-6 weeks postpartum. It is clinically defined by hypertension 9 and proteinuria, with or without pathologic edema. Incidence: hypertensive disorders complicate 6% to 8% of all pregnancies, preeclampsia accounts for 80% of these cases. The rate of preeclampsia has risen steadily by approximately 30% to since 1990 for all ages, races, and ethnic groups to the rate of 39.9 per 1000 live births. It is the most common medical complication of pregnancy and the second leading cause of maternal morbidity and mortality in the United States. Etiology: Not exactly known, but it is common in certain groups of females (toxemia prone). 1- Primigravida especially elderly primigravida. 2-Hypertension, chronic nephritis 3-Diabetes mellitus 4- Hydatidiform mole 5- Twin pregnancy 6- Hydramnios 7- Malnutrition 8- Fetal hydrops 9- Maternal genetic: PET runs in families because PET is dependent "'' upon 55 55 Chapter 5 Obstetrics and Gynecological Nursing a single recessive genes. Diagnosis: (A) Clinical picture of pre-eclampsia; 1) Hypertension: It is an early sign due to vasospasm, usually precedes clinical edema and proteinuria. The position of the person in whom the blood pressure is measured is important in pregnancy. The supine and right lateral positions are not recommended —» the effect of the gravid uterus on venous return leading to postural hypotension. Sitting or lying in the left lateral position with the sphygmomanometer cuff at the level of the heart. Diagnosed by: * BP > 140/90 on 2occasions , 6 hours or more apart. * There is a rise 15 mmHg in diastolic blood pressure or there is a rise 30 mmHg in systolic blood pressure compared to baseline reading before pregnancy or during 1st trimester. * Mean Arterial Pressure (MAP) = Diastolic + (Systolic - Diastolic) /3 A rise of 20 mmHg in MAP is ominous compared with 1st trimester. MAP 100 abnormal. MAP 105 indicates hypertension. 2) Edema : 2 types : * Occult edema : Usually develops before hypertension in the form of excessive weight gain (gain of 2 pounds. or more/week or 6 pounds or more/month are suggestive). * Manifest edema : Usually develops after hypertension at lower limb, lower abdomen, e. It is due to 56 56 Chapter 5 Obstetrics and Gynecological Nursing salt retention. 3) Proteinuria : Always develops after hypertension and is caused by anoxia of the glomerular capillaries due to spasm of the afferent arterioles.( presence of > 300 mg / litre in a 24 hour collection or presence of > 1 gm / litre in at least 2 random urine specimens 6 hours or more apart). Urine samples must be midstream or by catheterization. Proteinuria in the absence of Detection of proteinuria: a- Boiling test: - 10 cc urine in a test tube. - Boiling upper 1/3 of tube -> A cloud is formed. - Add few drops of acetic acid. - If the cloud dissolves -> phosphate. - If the cloud persists ->albuminuria b- Sulpha salicylic acid test: 10 drops sulpha salicyclic acid + 5 ml lear urine -> white cloud the amount and density of the cloud roughly indicates the amount of proteins. Trace or + or ++ or +++ or++++. c- Albustix (colour strips) : If albuminuria is present -> green color. The depth of green color correlates with the amount of protein in urine. In severe cases, the following manifestation (symptoms) may occur: (a) Eye symptoms: As blurring of vision, flashes of light or complete blinding due to retinal changes: * Vascular spasm. * Hemorrhage and exudates (cotton wool and fluffy appearance). * Edema of the optic disc. * Accumulation of sub retinal fluid. Retinal detachment in severe cases. Prognosis is good as they are reversible once pregnancy termination. 57 57 Chapter 5 Obstetrics and Gynecological Nursing (b) Headache (frontal): due to hypertension. (c) Oliguria and anuria: due to kidney pathology. (d) Epigastric pain: due to rapid enlargement and subcapsular hemorrhage of the liver, which stretch Glisson's capsule. , (e) Severe nausea and vomiting: due to congestion of gastric mucosa or cerebral edema. Investigations: 1- Complete urine analysis: to exclude urinary tract infection , and to detect and measure proteinuria. 2-Kidney function tests: blood urea, Serum creatinine, creatinine clearance test and serum uric acid. Serum uric acid increases as an early and sensitive indicator of the onset of pre-eclampsia. Level > 6 mg% is abnormal in pregnancy but gradually increasing levels are more significant. 3- Liver function tests: serum albumin, bilirubin and liver enzymes (SGOT and SGPT). 4- Tests of placental functions: daily fetal movement count, non-stress test , Oxytocin challenge test, fetal biophysical profile and Doppler velocimetry. 5- Ultrasound assessment of fetal growth by repeated measurement of biparietal diameter, femur length, abdominal circumference, estimated fetal weight and amount of amniotic fluid to detect intra-uterine growth retardation. 6- Fundus examination (by ophthalmologist): spasm, hemorrhage , papilledema, or retinal detachment. 7- ESTIMATION of coagulation index: PT, PIT, FDP and platelet count 58 58 Chapter 5 Obstetrics and Gynecological Nursing Management of pre-eclampsia 1- Prophylactic treatment: 1- Proper antenatal care. 2- Proper diet, decrease salt intake (2-4 gm daily), LOW carbohydrate , more protein, vitamins and minerals e.g. calcium and magnesium. 3- Prevent excessive weight gain. 4- Avoid prophylactic diuretics, as the circulating blood volume is already low. 5- Regular examination for BP, urine for albumin, and weight. 6- Antithrombic agent (low dose aspirin) 40-100 mg orally/day. It inhibits the production of platelet aggregating agent. II-Active treatment: The definitive treatment of PE is delivery of the fetus. Our policy is to manage conservatively pre-eclampsia occurring before 37 weeks provided that: 1- Mother is asymptomatic. 2- Blood pressure can be controlled. 3- Normal liver and renal function. 4- No signs of fetal distress. (A) General measures: 1) Bed rest: Physical and mental rest. 12 hours sleep in lateral recumbent position each night and rest periods during the day to facilitate renal and placental perfusion by mobilizing the movement of extracellular fluid back into the intravascular space. At home in mild pre-eclampsia. Hospitalization in severe pre-eclampsia however many centers 59 59 Chapter 5 Obstetrics and Gynecological Nursing preformed hospitalization in all cases of pre-eclampsia. 2)Balanced diet containing at least 60 to 70 g of protein, 400 mcg of folic acid, 1200 mg of calcium, adequate zinc, magnesium and vitamins is greatly recommended. There is no sodium restriction; however excessively salty foods should be avoided. Foods with roughage (whole grains, raw fruits, and vegetables) are encouraged. The woman is advised to drink six to eight glasses of water per day and avoid alcohol and caffeine intake 3) Observation : On admission, history, general and physical examination followed by daily search for development of such symptoms and signs -> headache, visual disturbance, epigastric pain and rapid weight gain. Weight measure on admission then every 2 days. Blood pressure every 4 hours. Urine: * Protein on admission then every 2 days. * Casts and cells indicative of underlying renal disease. Measurement of serum creatinine, uric acid and urea nitrogen repeat every week. Measurement of hematocrit, serum SGOT, repeated every week. Coagulation profile (PT, PTT, FDP and platelet count) repeated every week. Frequent evaluation of fetal size by serial sonography. Estimation of placental function and assessing fetal well-being by non-stress test (repeated according to severity of PE). Fundus examination (repeated every 2-3 days). (B) Medical measures: 1) Sedative: 30-60 mg phenobarbitone 4 times daily. 2) Diuretics: Lowers blood pressure and reduces edema. But, do not significantly reduce the incidence of proteinuric pre-eclampsia or 60 60 Chapter 5 Obstetrics and Gynecological Nursing improve perinatal outcome and are not useful in established pre eclampsia: - They cause hyperuricemia obscuring a useful sign. - Aggravate hypovolemia. - Reduced placental perfusion. So, we avoid their use except in management of pulmonary edema, which is a rare complication of pre-eclampsia. 3) Plasma volume expansion: Expansion of the blood volume may be required to improve the maternal systemic and uteroplacental circulation, there by preventing hypoxia and reducing the effect of hemorrhage. Clear fluids will leak out and aggravate pre-existing edema, therefore colloid solution such as hemaccel and gelofusine are used. These solutions increase the colloid osmotic pressure and pull fluid back into the circulation there by reducing the edema and increasing blood volume. (4) Hypotensives : given only when blood pressure > 160/110. Aim: to decrease maternal complications i.e. not curative. a) Methyl dopa (Aldomet): It is the first line of treatment. No evidence of long-term adverse effects in exposed infants. It has short half life and slow onset of action. It inhibits vasoconstriction by a centrally mediated effect. Treatment starts with a loading dose 500-750 mg orally followed by a maintenance dose of between 250 twice daily and 1 gm three times daily. b) Calcium channel blockers e.g. nifedipine which is the second line of treatment with no evidence of harm to the fetus. It is a Ca channel blocker which inhibits influx of Ca ions to vascular smooth muscle, resulting in arterial vasodilatation. The initial dose is 10 mg twice daily and may be increased to 40 mg twice daily. 61 61 Chapter 5 Obstetrics and Gynecological Nursing c) Other antihypertensive drug as: Reserpin injection, Apresolin = hydralazin by IV infusion then oral tablet, Labetalol (combined alpha and beta adrenergic blocker) and MgSO4 for imminent eclampsia. (c) Obstetric measures :Termination of pregnancy. Advantages: to minimize immediate and remote complications on the mother and fetus. Disadvantage : Prematurity and risk of termination method. Methods: If the cervix is favorable : artificial rupture of the membranes + pitocin drips. If the cervix is unfavorable : or obstetric indication for CS : LSCS. Indication: Mild pre-eclampsia: with improvement termination of pregnancy at the end of 37 Weeks or at term not beyond. Severe pre-eclampsia : termination of pregnancy. 1- All cases of pre-eclampsia when the fetus pass the hazards of prematurity (> 37 weeks). 2- Maternal blood pressure can't be safety controlled. 3- Mother will become symptomatic with signs of imminent eclampsia. 4- Mother will develop biochemical or hematological abnormality indicating that pregnancy cannot be safely controlled. 5- Severe pre-eclampsia + retinal changes. 6-Signs of fetal distress. 62 62 Chapter 5 Obstetrics and Gynecological Nursing (D) Management during labor: 1- Careful observation of the mother e.g. BP, pulse and proper sedation. 2- FHR monitoring during labor. 3- Shorten 2nd stage of labor by forceps or ventouse. 4- No ergometrine in the 3rd stage of labor except if there is postpartum hemorrhage. 5- Ergometrine will cause peripheral vasoconstrictipn and increase hypertension. (E) Care of the baby: Most babies are premature or growth retarded, so they should be handled by pediatrician. (F) Postpartum interventions for preeclampsia include close monitoring of the blood pressure and maternal condition. If blood pressure remains high after puerperium, the same antihypertensive drugs that are used during pregnancy seem to be the safest during breast feeding as long as they are taken at the lowest dose possible for hypertensive management (G) If the woman remains hypertensive, all types of contraception are available to her, provided that compliance and close follow up are guaranteed. The risks of oral contraceptives must be discussed completely if that method is considered. Prognosis: Depends on severity and duration of' PE. Immediate complication: 1- Convulsion and coma (eclampsia). 2- Bilateral renal cortical necrosis with renal failure. 3- Accidental hemorrhage. 4- Intrauterine fetal death due to placental insufficiency. 5- Cerebral hemorrhage. 63 63 Chapter 5 Obstetrics and Gynecological Nursing 6- Coagulation failure. 7- Premature birth and IUGR. 8- PP hemorrhage and shock. 9- HELLP syndrome: Hemolytic anemia, Elevated liver enzymes, Low Platelets. Remote complication: 1- Residual chronic hypertension (1/3 of cases). 2- Recurrent of PE in the following pregnancy. 64 64  Gestational Diabetes Mellitus (GDM) Objectives of this lecture: By the end of this lecture, the students will be able to:  Define gestational diabetes mellitus  Identify risk factors for gestational diabetes mellitus  Mention the effect of gestational diabetes mellitus on pregnancy  Explain the diagnosis for gestational diabetes mellitus during pregnancy.  Describe the management steps for gestational diabetes mellitus during pregnancy.  List the nursing care for gestational diabetes mellitus during pregnancy. 65 Introduction Insulin is a hormone which enable glucose in the bloodstream to enter the cells of the body, where used as a source of energy. Placenta produces hormones that make the mother resistant to her own insulin. Most pregnant women produce more insulin to compensate and keep their blood sugar level normal. Some pregnant women cannot produce enough extra insulin and their blood sugar level rises, a condition called gestational diabetes. Definition of GDM: It is any degree of glucose intolerance with onset of pregnancy or first recognition during pregnancy and considers the second most common medical disorders during pregnancy. Gestational diabetes is a condition in which a woman without diabetes develops high blood sugar levels during pregnancy. Incidence: Gestational diabetes mellitus is a common complication of pregnancy with short and long-term maternal, fetal, and newborn adverse outcomes and the prevention of pathological hyperglycemia during pregnancy is meaningful for global public health. The pooled global standardized prevalence of GDM was 14.0% ranged between 7.1% and 27.6% worldwide. Time of testing: Testing for gestational diabetes is usually done between 24th and 28th week of pregnancy for low risk women. However, testing may be done earlier in the pregnancy (first prenatal visit) if the woman has risk factors for gestational diabetes, such as: 66   Maternal age above 35 years or over  previous history of gestational diabetes in a previous pregnancy  Personal history of diabetes  Family history of type 2 diabetes or a first-degree relative (mother or sister) who has had gestational diabetes  Overweight or obesity  Polycystic Ovary Syndrome Causes for gestational diabetes mellitus: Although the cause of GDM is not known, there are some theories as to why the condition occurs. In pregnancy the placenta supplies a growing fetus with nutrients and water, and also produces a variety of hormones to maintain the pregnancy. Some of these hormones (estrogen, cortisol, and human placental lactogen) can have a blocking effect on insulin. This is called contra-insulin effect or insulin resistance, which usually begins about 20 to 24 weeks into the pregnancy. As the placenta grows, more of these hormones are produced, and the risk of insulin resistance becomes greater. Normally, the pancreas is able to make additional insulin to overcome insulin resistance, but when the production of insulin is not enough to overcome the effect of the placental hormones, gestational diabetes results. Effect of Pregnancy on Diabetes:  Pregnancy is diabetogenic due to increased production of human placental lactogen, placental insulinase, cortisol and progesterone. 67   Insulin requirements: increases during pregnancy due to increased production of placental hormones while it decreases postpartum. Effect of diabetes on pregnancy (complications):  Maternal complications: 1-During pregnancy: Preeclampsia, preterm labour, monilial vulvo vaginitis, urinary tract infection and Placenta previa: due to large placenta. 2- During labor:  Prolonged and obstructed labor due to large sized baby.  Shoulder dystocia  Birth canal injuries 3-During puerperium:  Puerperal sepsis  Postpartum hemorrhage 68   Increase risk of type 2 diabetes  Breast infection and lactation failure.  Fetal complications:  Abortion.  Polyhydramnios: due to large placenta and fetal size.  Congenital anomalies: due to uncontrolled diabetes during fetal organogenesis.  Preterm labor: with its complications. (RDS)  Intrauterine fetal death: especially in the last 4 weeks due to: ketosis, hypoglycaemia, pre-eclampsia, congenital anomalies, and placental insufficiency.  Fetal macrosomia: it is defined as fetal birth weight is>4.1kg  Causes: maternal hyperglycemia → fetal hyperglycemia →increase fetal insulin secretion (hyper insulinaemia) leads to excessive deposition of fat, glycogen &protein and enlargement of fetal organs because insulin is growth factor.  Neonatal Hypoglycemia: due to hyperinsulinaemia.  Neonatal morbidity and mortality. 69 Assessment of gestational diabetes  History  Examination  Investigation History  Previous GDM  Family history of diabetes  Preeclampsia  Polyhydramnos  Abortion  Preterm labor  Delivery of large baby Screening tests for G.D:  First method: woman taken 50gm glucose which ingested orally and venous blood samples withdrawn 1hour later. 70  Result: normal screen if blood glucose level is 140mg \dl and If >140mg\dl, oral glucose tolerance test G.T.T must be done  Oral glucose tolerance test: it is done by measuring blood sugar level when the woman is (fasting 8-14 hours), then again after one, two, and three hours after the ingestion of 100gm of glucose orally and a venous blood samples were taken (when the patient is fasting and after1, 2 and 3 hours). Diagnostic Criteria for 100-g glucose Challenge Test: Two or more of the following indicates diagnosis of gestational diabetes mellitus:  95 mg/dl or higher fasting blood glucose  180 mg/dl or higher at 1-hour postprandial blood glucose  155 mg/dl or higher at 2-hour postprandial blood glucose  140 mg/dl or higher at 3-hour postprandial blood glucose Second method: Measuring blood sugar level when the woman is (fasting 8-14 hours), then again after one and two hours after the ingestion of 75gm of glucose orally and a venous blood samples were taken (when the patient is fasting and after1 and 2 hours). Antenatal care Women should be seen at a combined antenatal and diabetic clinic Frequent antenatal visits: for maternal and fetal follow up. Diet: restriction of carbohydrates, less fat and more proteins and vitamins. Exercises Insulin therapy Oral hypoglycemics are contraindicated during pregnancy; labor and early puerperium as they are not adequate for controlling diabetes, have teratogenic effects and may result in neonatal hypoglycemia. 71 Keeping blood sugar level under control Management of Labor and delivery: 1. Timing: pregnancy is terminated at 37 completed weeks to avoid intrauterine fetal death. 2. Mode of delivery: vaginal delivery is induced in normal presentation, favorable cervix, average sized baby and no fetal distress. Otherwise, caesarean section is indicated. 3. Monitor fetal condition throughout the labor 4. Careful observation for PPH Neonatal care: The neonate is managed as a premature baby as it is more liable for RDS.  Newborn should be examined carefully for congenital abnormality. 72  The baby should be fed soon after delivery to prevent hypoglycemia as the baby continues to produce insulin than he needs. (to avoid brain damage). Post-natal care:  Carbohydrate metabolism returns to normal within 24 hours after delivery and insulin requirements will fall rapidly.  Careful observation for PPH  Diabetic mother is liable to infection: advice women to change pads frequently and keep any wound clean and dry. Contraception  Barrier methods ( condom and diaphragm) ….The best  Combined hormonal contraceptive pills: are contraindicated as it increases hyperglycemia.  Progestin only pills can be used as it not cause metabolic changes.  Intra uterine device (IUD): increase risk of pelvic infection. 73  References 1- Musa, E., Salazar‐Petres, E., Arowolo, A., Levitt, N., Matjila, M., & Sferruzzi‐Perri, A. N. (2023): Obesity and gestational diabetes independently and collectively induce specific effects on placental structure, inflammation and endocrine function in a cohort of South African women. The Journal of Physiology, 601(7), 1287-1306.‫‏‬ 2- Ramezani Tehrani, F., Naz, M. S. G., Yarandi, R. B., & Behboudi- Gandevani, S. (2021): The impact of diagnostic criteria for gestational diabetes mellitus on adverse maternal outcomes: a systematic review and meta- analysis. Journal of clinical medicine, 10(4), 666.‫‏‬ 3- Wang, H., Li, N., Chivese, T., Werfalli, M., Sun, H., Yuen, L., & Yang, X. (2022): IDF diabetes atlas: estimation of global and regional gestational diabetes mellitus prevalence for 2021 by International Association of Diabetes in Pregnancy Study Group’s Criteria. Diabetes research and clinical practice, 183, 109050.‫‏‬ 74 Chapter 6 Obstetrics and Gynaecological Nursing Normal labor Unit objectives: At the end of this unit, the student should be able to: 1. Define normal labor 2. Identify the main causes of onset of labor 3. Outline premonitory signs of labor 4. Compare and contrast true versus false labor 5. Discuss the critical factors affecting labor and birth 6. List the cardinal movements of labor 7. Identify the maternal and fetal response to labor and birth 8. Describe the stages of labor and critical events occurring during each stage 9. Recognize the normal physiologic changes occurring during all four stages of labor 10. Discuss the ongoing assessment involved in each stage of labor and birth 11. Delineate the nurse’s role throughout the labor and birth process 75 Chapter 6 Obstetrics and Gynaecological Nursing Anatomy of the Female Reproductive System The Bony Pelvis: The bony pelvis is composed of 4 bones: 1- Two innominate or hip bones 2- One sacrum 3- One coccyx Innominate or hip bone is divided into: A) Ilium parts: -Iliac fossa. -Iliac crest. -Anterior iliac spine. -Posterior iliac spine. - 2/5 acetabulum. 76 Chapter 6 Obstetrics and Gynaecological Nursing 77 Chapter 6 Obstetrics and Gynaecological Nursing B)Ischum parts: -Ischeal tuberosity -Ischeal spine - 2/5 acetabulum C) Pubis parts: -Body and superior and inferior rami -Symphysis pubis - 1/5 acetabulum SACRUM: - 5 sacral vertebrae fused together. - Sacral promontory and ala on each side of it. COCCYX: - 4 small rudimentary coccygeal vertebrae fused together. 78 Chapter 6 Obstetrics and Gynaecological Nursing Differences between the male and female pelvis: CHARACTERISTIC MALE FEMALE Bones Heavier, rougher Lighter, delicate Size Smaller Larger Sacrum Narrow, curved Broader, less curved Symphysis pubis Deeper Shallower Ischeal tuberosity Inverted Everted Inferior pubic angle Narrower Wider (90°) Ischeal spine Bigger Smaller Coccyx Less movable Movable False pelvis Tall Flaired Pelvic inlet Android Gynecoid Pelvic vavity Funnel-shaped Less funnel shaped Pelvic outlet Smaller Larger ** Birth Canal is divided into: (1) Major (greater or false) pelvis (2) Minor (Lesser, deep or true) pelvis True Conjugate diagonal Obstetric a- Inlet Measurements Oblique Transverse b- Cavity Transverse c- Outlet Measurements Transverse mid plane antero posterior 79 Chapter 6 Obstetrics and Gynaecological Nursing Measurements of the true pelvis: Anteroposterior Oblique Transverse Inlet 11 cm. 12 cm. 13 cm Cavity 12 cm. 12 cm. 12 cm. Outlet 13 cm. 12 cm. 11 cm ( 1 ) The major (greater or false) pelvis : Is that portion of the bony pelvis between the iliac crests and the pelvic brim: a. Laterally, the alar plates of the ilia. b. Posteriorly L3, L4 and L5. c. Anteriorly, the anterior abdominal wall. ( 2 ) The minor (Lesser, deep or true) pelvis: Lies inferiorly to the pelvic brim. A- The pelvic inlet = pelvic brim Demarcates the minor from the major pelvis. It is defined by the sacral promontory and the linea terminalis of the innominate bone. 80 Chapter 6 Obstetrics and Gynaecological Nursing Measurement of the female pelvic inlet: Conjugate diameters: * The true conjugate diameter (10 cm). Is the anteroposterior diameter from the sacral promontory to the superior margin of the sympysis pubis. This can be measured only radiographically. 81 Chapter 6 Obstetrics and Gynaecological Nursing BONY PELVIS-BRIM 82 Chapter 6 Obstetrics and Gynaecological Nursing  The diagonal conjugate (12.5cm). Is measured from the sacral promontory to the inferior margin of the pubic symphysis. This is easily noted on pelvic examination.  The obstetric conjugate (10.5cm). Is the least anteroposterior diameter from the sacral promontory to a point a few millimeters below the superior margin of the pubic symphysis.  The oblique diameter (12.5 cm).Is measured from the sacroiliac joint to the contralateral ilio-pectineal eminence.  The transverse diameter (13.5 cm). Is the widest distance across the pelvic brim B- The pelvic cavity: Is defined by minor pelvis, forms the birth canal, and contains portion of the gastrointestinal tract as' well as the lower portion of the urinary tract and certain reproductive organs. Pelvic inclination:By this is meant the angle that any pelvic plane makes with the horizontal. In the erect position the brim is normally inclined at 60 degrees. 83 Chapter 6 Obstetrics and Gynaecological Nursing C - The pelvic outlet: Is closed by the pelvic diaphragm and covered by the perineum. It is defined by thecoccyx, ischial tuberosities, and inferior bubic symphysis. ◙ During pregnancy the ligaments of the sacro - iliac joints and the symphysis pubis become softened and there is slightly increased mobility at these joints. The sacrococcygeal joint allows the coccyx to move freely backward during delivery. 84 Chapter 6 Obstetrics and Gynaecological Nursing Measurements of the female pelvic outlet:  The transverse diameter (11 cm). Is between the ischial tuberosities. It is approximately aslong as a clenched fist is wide.  The transverse midplane diameter (10.5 cm). Is measured between the ischial spines  The anteroposterior (Sagittal) diameter (13.5 cm). Is measured from the lower margin of the pubic symphysis to the sacrococcygeal joint. 85 Chapter 6 Obstetrics and Gynaecological Nursing N.B. Thorn's Dictum states that for spontaneous delivery to take place, the transverse of the outlet plus the posterior sagittalmust be equal at least 15 cm. # The girdle of contact of the head  It is the circumference of the head which first comes in contact with the pelvic brim. This circumference varies according to the length of the engaging diameters.  In a well flexed vertex presentation, it forms a rounded circle, as both the antero-posterior and transverse diameters measure 9.5 cm. This rounded shape is quite.  favourable in preventing premature rupture of the membranes it fits in the lower uterine segment and effectively separates the hind waters from bag of fore waters. 86 Chapter 6 Obstetrics and Gynaecological Nursing  In deflexed vertex and I or other abnormal presentations, the girdle of contact is oblong or uneven, allowing free communication between the hind waters and the bag of forewaters and hence predisposes to premature rupture of membranes. The pelvic axis: The axis of the pelvis is an imaginary curve line which shows the path which the- centre of the fetal head follows during its passage through the pelvis. It is obtained by taking several antero-posterior diameters of the pelvis and joining their centers. Pelvic joints: a) Sacro-iliac joint: between the sacrum and ilium. b) Sacro-coccygeal joint: between the Pelvic Joints: sacrum ana coccyx. c) Symphysis pubis joint: between the two bodies of the pubis. Pelvic ligaments: *Sacrotuberous ligament *Sacroi!iac ligament * lliolumbar ligament PELVIC LIGAMENTS Ligaments support inside the pelvis: Broad Ligament: It is a peritoneal fold extending from the pelvic wall to the lateral borders of the uterus. It contains, the fallopian tube, the uterine, ovarian vessels, lymphatics and nerves, mesonephric remnants and considerable amount of connective tissues. 87 Chapter 6 Obstetrics and Gynaecological Nursing Round Ligament: It is a fibro-muscular band arises at the cornu of the uterus anterior to the tubal insertion and passes in the inguinal canal to be inserted into the labium majus of the vulva. Ovarian Ligament: It is a fibro-muscular band which link the ovary to the cornu of the uterus posterior to tubal insertion. Cardinal ligament "Mackenrodt's ligament": It is formed of a condensed endopelvic fascia extending from the supra-vaginal cervix and the upper vaginato the lateral pelvic wall. Utero-sacral Ligament: It is a condensed end pelvic fascia extending from the back of the supra-vaginal cervix and upper vagina to the sacrum. The pelvic floor: This is the soft tissue filling the pelvic bony outlet consists from above downwards: *The pelvic peritoneum. * The pelvic fascia. * The levator ani muscles and coccygeus muscle. * The perineal muscles. * The skin of the perineum. Subdivisions of pelvic floor muscles (pelvic diaphragm): 1-lliococcygeus 2- Pubococcygeus Levator ani 3- Puborectalis · 4- Ischiococcygeus 88 Chapter 6 Obstetrics and Gynaecological Nursing Actions: * Supports the pelvic organs. *Acts as a sphincter tothe urethra and rectum. * Important for internal rotation of the head during labor. # N.B. Injuries to the pelvic floor during labor predispose to genital prolapse and stress incontinence of urine. 89 Chapter 6 Obstetrics and Gynaecological Nursing The perineum Definition: The structures filling the lower pelvic aperture. Boundaries: Anterior : Symphysis pubis Lateral : Ischial tuberosities Posterior : Coccyx Divisions: An immaginary line between the two ischial tuberosities divides the perineum into two triangles. Anal triangle: The principle structures of the anal triangle are; the anal canal, the anus and the terminal portion of the gastrointestinal canal. Urogenital triangle: The principle structure of the urogenital triangle is the external genitalia 90 Chapter 6 Obstetrics and Gynaecological Nursing Labor: is a series of events that takes place in the genital organ in an effort to expel the viable products of conception out of the uterus through birth canal into the outer world. It may occur prior to 37 completed weeks, when it is called preterm labor. Delivery: is the expulsion or extraction of viable fetus out of the uterus (receive the neonate). Normal labor (Eutocia): Labor is called normal if it fulfills the following criteria: Spontaneous expulsion of a single, mature (37-42 completed weeks of pregnancy) alive fetus, presenting by vertex, through the natural passages (birth canal), within a reasonable time, without fetal or maternal complications and without any interventions except episiotomy. Abnormal labour (Dystocia): Any deviation from the definition of normal labour is called abnormal labor. Prolonged labor: When duration of labor lasting >24 hours. Precipitate labor: When duration of labor lasting < 3 hours. Causes of Labor: Theories It is unpredictable to foretell precisely the exact date of onset of labor. Several theories have been advanced to explain what initiates labor. 91 Chapter 6 Obstetrics and Gynaecological Nursing (I) Hormonal factors: 1-Increased estrogen hormone level and decreased progesterone hormone level. 2-Prostaglandin Release  Prostaglandins E2 and F2α are powerful stimulators of uterine muscle activity and ripening of the cervix.  Fetal membranes and decidua vera have prostaglandin synthetize and produce prostaglandins.  Mechanical stimulation known to cause the release of prostaglandins (e.g. cervical manipulation, stripping of the membranes, and rupture of the membranes) augment or induce uterine contractions. 3-Oxytocin: Oxytocin receptors are increased in the uterus with the onset of labor. Oxytocin promotes the release of prostaglandins from the decidua. Vaginal examination and amniotomy cause rise in maternal plasma oxytocin level. 4-Foetal cortisol theory: Increased cortisol production from the foetal adrenal gland before labor may influence the onset of labor by increasing oestrogen production from the placenta. 92 Chapter 6 Obstetrics and Gynaecological Nursing II) Mechanical factors: (1) Uterine distension theory: Like any hollow organ in the body, when the uterus in distended to a certain limit, it starts to contract to evacuate its contents. This explains the preterm labor in case of multiple pregnancy and polyhydramnios. (2) Stretch of the lower uterine segment: by the presenting part near term. III- Artificial Cervical exam (PV), artificial rupture of membranes, nipple Stimulation and sexual activity Prodromal signs of labor (Premonitory Symptoms and Signs of Labor): as lightening, cervical changes and appearance of false pain (1) Lightening & Shelfing: Lightening occurs when the fetal presenting part begins to descend into the maternal pelvis The fundus of the uterus descends slightly and falls forwards giving the upper part of the abdomen a special form as a shelf detected in the standing position. The value of shelfing is to bring the fetus in the direction of axis of the pelvic inlet. 93 Chapter 6 Obstetrics and Gynaecological Nursing With this descent, the woman usually notes that her breathing is much easier. However, she may complain of increased pelvic pressure, cramping, and low back pain. She also may note edema of the lower extremities as a result of the increased stasis of blood pooling, an increase in vaginal discharge, and more frequent urination. In primiparas, lightening can occur 2 weeks or more before labor begins, and among multiparas it may be as late as during labor. (2) Cervical changes Before labor begins, cervical softening and possible cervical dilation with descent of the presenting part into the pelvis occurs. As the time for labor approaches, the cervix changes from an elongated structure to a shortened, thinned segment. (3) False Labor Pains (Braxon-Hicks contraction): Irregular intermittent contractions; “false labor False Labor pains 1. Contraction occur at irregular intervals. 2. The contraction intervals are long and do not establish a regular pattern. 3. The intensity of the contractions remains the same. 4. The discomfort is chiefly in the lower abdomen. 5. Contractions are usually relieved and are often stopped by sedation. 6. Contractions do not cause dilatation of the cervix because they are not coordinated and lack fundal dominance. 94  Chapter 6 Obstetrics and Gynaecological Nursing True Labor Pains 1. Contractions occur at regular intervals, and the intervals gradually shorten to 2 - 4 minutes apart. 2. The intensity of the contractions gradually increases with contractions lasting 1 minute. 3. The discomfort is in both the back and the abdomen. 4. Progressive dilatation of the cervix occurs. 5. Contractions are not affected by sedation. Factors affecting the labor process (five Ps): 1. powers (uterine contractions and retraction & maternal bearing down) 2. passageway ( bony pelvis and birth canal) 3. passenger (fetus and placenta) 4. position (maternal) 5. psychological response However, there may be additional factors that affect the labor process as well: 1. partner ( support caregivers) 2. patient preparation (childbirth knowledge base) 3. pain control; (comfort measures)  Myometrial Physiology 95 Chapter 6 Obstetrics and Gynaecological Nursing The contraction wave of the uterus begins in the fundus which contains the greatest concentration of myometrial cells and moves downward throughout the entire myometrium. Myometrial contraction efficiency depends on the presence of 5 factors. a. Gap junction must be present. Gap junction of the myometrium arc cell to cell contracts that promote synchronous contractions of smooth muscle cells and increase the effectiveness of the contractions. Gap Junctions are prevalent at term and increase during labor in number and size. They begin to disappear within 24 hours after delivery. b. The contractile substances actin and myosm areessential for muscle contraction to occur. c. A source of energy adinosin triphosphate must beavailable.. d. Cellular electrolyte exchange of calcium, sodium and potassium is essential for muscle contraction. e. The presence of an endocrine stimulus is necessary for conduction of muscle contraction.  Nature of Uterine Contractions Uterine contractions are involuntary and occur even when parturient woman is unconscious, regular and painful. Uterine contractions are rhythmic and intermittent, with a period of relaxation between contractions. This pause allows the woman and the uterine muscles to rest. In addition, this pause restores blood flow to the uterus and placenta, which is temporarily reduced during each uterine contraction. 96  Chapter 6 Obstetrics and Gynaecological Nursing At first contractions occur every 20 - 30 minutes and last for about 30 second, but they gradually increase in frequency and duration until by the end of the first stage, they recur every 2 - 3 minutes for about a full minute. ** Causes of painful Contractions: (a) Hypoxia of the contracted myometrium (as m angina pectoris). (b) Compression of nerve ganglia in the cervix and lower uterus by the tightly interlocking muscle fibers. (c) Stretching of the cervix during dilatation. (d) Stretching of the peritoneum overlying the uterus. Each contraction has three phases: increment (buildup of the contraction), acme (peak or highest intensity), and decrement (descent or relaxation of the uterine muscle fibers  To describe the uterine contractions in labor, certain definitions should be recognized: 97 Chapter 6 Obstetrics and Gynaecological Nursing The Tonus (T) This is the intrauterine pressure in between uterine contractions The Intensity or Amplitude (A) This is the raise in the intrauterine pressure produced by the uterine contractions (about 40 mm Hg) The Frequency This is the number of contractions per 10 minutes. The Duration (D) This is the time of uterine contraction from the time it starts till it completely ceases 98 Chapter 6 Obstetrics and Gynaecological Nursing In LABOUR when the muscle fibres relax they do not return to their former length but become progressively shorter' This is RETRACTION. 99 Chapter 6 Obstetrics and Gynaecological Nursing Retraction: The muscle fibres of the upper segment of the uterus not only contract but retract. When contracting, the fibres become shorter and thicker. When the active contraction passes of the fibres lengthen again, but not to their original length, i.e. some of the shortening of the fibres is maintained. Each successive contraction starts where the previous one ended, so that the upper uterine segment