Pregnancy Stages PDF

DECIDUA OR UTERINE LINING - after fertilization the corpus luteum in the ovary continues to function rather than atrophies, Human Chorionic Gonadotropin secreted by the trophoblast cell will cause the uterine endometrium to continue to grow in thickness and vascularity instead of sloughing off as in...

DECIDUA OR UTERINE LINING - after fertilization the corpus luteum in the ovary continues to function rather than atrophies, Human Chorionic Gonadotropin secreted by the trophoblast cell will cause the uterine endometrium to continue to grow in thickness and vascularity instead of sloughing off as in a usual menstrual cycle. The endometrium is now called decidua and it will be discarded after birth of the child. CHORIONIC VILLI – these resembling probing fingers will reach out from the trophoblast cell into the uterine endometrium to begin formation of the placenta. These villi will also produce various placental hormones present during pregnancy which are HCG (Human Chorionic Gonadotropin ), HPL (human placental lactogen), estrogen and progesterone.Later on you will learn more about these great hormones and their function. PLACENTA – It grows from a few identifiable trophoblastic cells at the beginning of pregnancy , its major function is to serve as a transport allowing all but a few substances to cross from the mother into the fetus. THE AMNIOTIC MEMBRANES – is a dual-walled sac with the chorion as the outermost part and the amnion as the innermost part. The two fuse together as the pregnancy progresses and by the term, they appear to be as a single sac. They have no nerve supply so when they spontaneously ruptures or artificially neither the pregnant woman nor the fetus experiences any pain (Coad&Dunstall.2011). THE AMNIOTIC FLUID - the fetus continuously swallows this fluid and it is absorbed from the fetal intestine into the fetal blood stream, at term it is approximately 800-1200 ml. The most important purpose of the amniotic fluid is to shield the fetus against pressure or blow to the mother’s abdomen. It also protects the umbilical cord from pressure thus protecting the fetal oxygen supply. THE UMBILICAL CORD – is formed from the fetal membranes, the amnion and chorion and provides a circulatory pathway that connects the embryo to the chorionic villi of the placenta. Its function is to transport oxygen and nutrients to the fetus from the placenta and to return waste products from the fetus to the placenta. An umbilical cord contains only one vein (carrying blood from the placenta to the fetus) and two arteries (carrying blood from the fetus back to the placenta). HUMAN CHORIONIC GONADOTROPIN – This is the first placental hormone produced that can be found in maternal blood and urine as early as the first missed period. Its purpose is to act as a fail-safe measure to ensure the corpus luteum of the ovary continues to produce progesterone and estrogen so the endometrium of the uterus is maintained. It also plays a role in suppressing the maternal immunologic response so placental tissue is not detected and rejected as a foreign substance. ESTROGEN – is often referred to as “the hormone of women”. It contributes to the woman’s mammary gland development in preparation for lactation and stimulates uterine growth to accommodate the developing fetus. PROGESTERONE – This is often referred to as “hormones that maintains pregnancy”, it is necessary to maintain the endometrial lining of the uterus during pregnancy. It is present in the maternal serum or blood as early as 4th week of pregnancy. It also prevents premature labor as it reduces the contractility of the uterus during pregnancy. HUMAN PLACENTAL LACTOGEN – it is a hormone with both growth promoting and lactogenic (milk-producing properties). By 6th weeks it will be produced by the placenta increasing to a peak level at term. It promotes mammary gland growth development in preparation for lactation and stimulates uterine growth to accommodate the developing fetus. CARDIOVASCULAR SYSTEM This is one of the first systems to become functional in intrauterine life. 16th day of life of the fetus = there is already a network of blood vessels and single heart tube. 24th day of life of the fetus = fetal heartbeat is evident. 10th to 12 th week of pregnancy = the fetal heartbeat maybe heard with a Doppler. After the 28th week of pregnancy = the heart rate stabilizes and a 110 to 160 beats/min is assessed. RESPIRATORY SYSTEM 3rd week of intrauterine life = the respiratory and digestive tracts exist as a single tube. End of 4th week = a septum begins to divide the esophagus from the trachea. 3 months gestation = spontaneous respiratory practice movements begins and continue throughout pregnancy. SURFACTANT = this develops at approximately 24th week of pregnancy. Its primary function is to improve the infant’s ability to maintain respirations in the outside environment after birth (Rojas-Reyes, Morley & amp; Soll 2012). NERVOUS SYSTEM 3rd week of gestation = the top portion of the neural plate will differentiate into the neural tube which will form the CNS (Central Nervous System) which is the brain and spinal cord. The neural crest will form the PNS (Peripheral Nervous System). All parts of the brain ( cerebrum, cerebellum, pons and medulla oblongata) form in utero but not completely mature at birth. Brain growth continues at high levels until 5 or 6 years of age. The eye and inner ear develop as a projection of the original neural tube. By 24 weeks the ear is capable of responding to sounds and the eyes exhibits a pupillary reaction indicating sight is present. ENDOCRINE SYSTEM The fetal pancreas produces insulin needed by the fetus (insulin doesn’t cross the placenta). The thyroid and parathyroid glands play a vital roles in fetal metabolic function and Calcium balance. The fetal adrenal glands supply a precursor necessary for estrogen synthesis by the placenta. DIGESTIVE SYSTEM 4th week of intrauterine life the digestive tract separates from respiratory tract and begins to grow rapidly. MECONIUM – this is a collection of cellular wastes, bile, fats, mucoproteins, mucopolysaccharides and portion of the vernix caseosa that accumulates in the intestine as early as the 16th week. Meconium is sticky in consistency and appears black or dark green (obtaining its color from bile pigment). The GI tract is sterile at birth because Vitamin K is necessary for blood clotting and is synthesized by the action of bacteria in the intestines. At 32 weeks gestation sucking and swallowing reflex are now mature but will become strong when fetus reaches its term. At 36 weeks gestation, the ability of the of the GI tract to secrete enzymes essential for carbohydrate and protein digestion is present. Amylase an enzyme found in saliva that is necessary for digestion of complex starches will only mature at 3 months after birth. Newborns also doesn’t have lipase an enzyme needed for fat digestion that is why breast milk is best for newborns because it can easily be digested without these enzymes. The liver is active throughout intrauterine life functioning as a filter between the incoming blood and the fetal circulation and as a deposit site for fetal stores such as iron and glycogen. MUSCULOSKELETAL SYSTEM First 2 weeks of life, cartilage prototypes provide position and support to the fetus. Ossification of this cartilage into bone begins at about the 12 th week and continues all through fetal life and into adulthood. REPRODUCTIVE SYSTEM A child’s sex is determined at the moment of conception by a spermatozoon carrying an X or a Y chromosome and can be ascertained as early as 8 weeks by chromosomal analysis. The male or father of the baby carries XY chromosomes, while the mother carries an X chromosomes. The father will determine the fetal sex, if X will be paired with Y it will become XY (male fetus). If X will be paired with X it will become XX (female fetus). The testes first form in the abdominal cavity and do not descend into the scrotal sac until 34th to 38th week of intrauterine life. URINARY SYSTEM Kidneys are present as early as the end of the 4 th week of intrauterine life, the presence of kidneys does not appear to be essential for life before birth because the placenta clears the fetus of wastes products. Urine is formed by the 12 th week and is excreted in the amniotic fluid by the 16 th week of gestation. INTEGUMENTARY SYSTEM The skin of a fetus appears thin and almost translucent until subcutaneous fat begins to be deposited underneath it at about 36 weeks, skin is covered with lanugo, soft downy hairs that serves as insulation to preserve warmth in utero as well as cream cheese like substance vernix caseosa which is important for lubrication and from keeping the skin from macerating in utero. Both vernix and caseosa are present at birth. IMMUNE SYSTEM Immunoglobulin (Ig) G maternal antibodies cross the placenta into the fetus as early as the 20th week and certainly by the 24th week of intrauterine life to give a fetus temporary passive immunity against diseases for which the mother has antibodies. IgA and IgM antibodies (the types which develop to actively counteract infection ) cannot cross the placenta, their presence in the newborn is a proof that the fetus has been exposed to an infection. REPRODUCTIVE SYSTEM CHANGES Reproductive tract changes are those involving the uterus, ovaries, vagina and breasts. The most obvious alteration in a woman’s body during pregnancy is the increase in the size of the uterus to accommodate the growing fetus. UTERINE CHANGES: UTERUS – increases in size to accommodate the growing fetus. Length: from 6.5 cm to 32 cm Width: from 4cm to 24 cm Depth: from 2.5 to 22 cm Weight: from 50g to 1000g BREAST CHANGES – typical changes are feeling of fullness, tingling or tenderness that occurs because of the stimulation of the breast tissue by the high estrogen level in her body. As the pregnancy progresses, breast size increases because of the growth in the mammary alveoli and in fats deposit. The areola of the nipple darkens and its diameter increases from about 3.5cm to 5cm. There is additional darkening of the skin surrounding the areola in some women, forming a secondary areola. The breast will begin to be ready for the secretion of milk, by the 16th week colostrum, the thin watery, high protein fluid that is the precursor of breast milk can be expelled from the nipples. As vascularity of the breasts increases, blue veins may become prominent over the surface of the breasts. The sebaceous glands of the areola (Montgomery’s tubercles) which keep the nipple supple and helps to prevent nipples from cracking and drying during lactation, enlarge and become protuberant. ENDOCRINE SYSTEM CHANGES Almost all aspects of the endocrine system increase during pregnancy in order to support fetal growth PLACENTA: Produces estrogen and progesterone (which helps maintain pregnancy), HCG (which allows detection of early pregnancy). PITUITARY GLAND: It produces increased levels of prolactin (milk production); produces oxytocin which is necessary for labor contraction. THYROID: Increases levels of hormones that increase the basal metabolic rate by 20% and can lead to increase emotional lability, perspiration, tachycardia and palpitations. ADRENAL GLANDS : Increases level of corticosteroids and aldosterone inhibits immune response thereby preventing rejection of fetus. PANCREAS: Increases insulin production but insulin is less effective due to estrogen, progesterone. This allows for more glucose to to be circulating in the maternal blood stream to be available to the fetus. INTEGUMENTARY SYSTEM CHANGES The uterus increases in size the abdominal wall stretches then causes rupture and atrophy of small segments of the connective layer of the skin leading to striae gravidarum in the thighs and abdominal wall. The umbilicus also stretches by 28th week of pregnancy and becomes obliterated and pushed and appears it has turned inside out protruding as a round bump at the center of the abdominal wall. A narrow brown line called linea nigra may form running from the umbilicus to the symphysis pubis. Darkened or reddened areas may appear on the face as well and on cheeks and nose known as melasma or chloasma or the “mask of pregnancy”. RESPIRATORY SYSTEM CHANGES A local change that often occurs here is congestion or stuffiness of the nasopharynx as a response to increased estrogen levels. Towards the end of pregnancy the diaphragm is displaced by as much as 4cm upward. CARDIOVASCULAR AND HEMATOLOGIC SYSTEM CHANGES Changes in the circulatory system are extremely significant to the health of the fetus because they determine whether there will be adequate placental and fetal circulation for oxygenation and nutrition. GASTROINTESTINAL SYSTEM CHANGES Nausea and vomiting are experienced earlier in pregnancy and this is the first sensation a woman experiences with pregnancy. It is most apparent early in the morning on rising and if tired during the day. It is known as morning sickness, it is felt at the same time the HCG and progesterone begins to rise. GENITOURINARY SYSTEM CHANGES Like any other systems, the urinary system undergoes specific physiologic changes during pregnancy, including alterations in fluid retention and renal, ureter and bladder functions. These changes are due to the following : effects of high estrogen and progesterone, compression to the bladder and ureters by the growing uterus, increase blood volume to the kidneys that results to increase in urine production and lastly postural influences by the pregnant woman. MUSCULOSKELETAL SYSTEM CHANGES Calcium and Phosphorus needs are increased during pregnancy because an entire fetal skeleton must be built. The ovarian hormones relaxin and placental progesterone softens the woman’s pelvic ligaments and joints to create pliability and to facilitate the passage of the baby through the pelvis at birth. IMMUNE SYSTEM CHANGES Immunologic competency during pregnancy decreases , probably to prevent a woman’s body from rejecting the fetus as if it were a transplanted organ. Immunoglobulin G (IgG) production is decreased , that makes a woman prone to infection during pregnancy. AMENORRHEA Absence of menstruation MELASMA Dark pigment forms on face QUICKENING Fetal movement felt by woman LINEA NEGRA Line of dark pigment forms on the abdomen STRIAE GRAVIDARUM Stretchmarks form on the abdomen TINGLING SENSATION in Feelings of tenderness, fullness, tingling, BREAST enlargement and darkening of areola NAUSEA & VOMITING Upon arising or when in fatigue FREQUENT URINATION Sense of being have to void more often than usual. FATIGUE General feeling of tiredness. PROBABLE SYMPTOMS OF PREGNANCY CHADWICK’S SIGN Color change of vagina from pink to violet GOODELL’S SIGN Softening of the cervix HEGAR’S SIGN Softening of the lower uterine segment BALLOTTEMENT When lower uterine segment is tapped on a bimanual examination the fetus can be felt to rise against the abdominal wall BRAXTON HICKS Periodic uterine tightening occurs CONTRACTION FETAL OUTLINE FELT BY Fetal outline can be palpated through EXAMINER abdomen POSITIVE SYMPTOMS OF PREGNANCY PRESENCE OF FETAL Presence of fetal heartbeat heard HEARTBEAT through stethoscope or Doppler FETAL MOVEMENTS FELT An examiner can feel fetal movements BY EXAMINER about 20-24th weeks VISUALIZATION OF THE If a woman is pregnant, a characteristic FETUS by ULTRASOUND ring indicating the gestational sac will be revealed and with a beating fetal heart The overall purposes of prenatal care includes: 1. To establish a baseline of present health of the mother. 2. To determine the age of gestation of the fetus. 3. To monitor maternal well being and fetal development. 4. To identify women who are at risk in developing maternal complications. 5. Provide health education about pregnancy, lactation and newborn care. Women should schedule a first prenatal visit as soon as they suspect that they are pregnant, the return appointments are usually scheduled every 4 weeks. WEIGHT GAIN in pregnancy occurs from both fetal growth and an accumulation of maternal stores and increases by 1.5 lb per month during the first trimester and 1 lb per week during the last two trimesters. To summarize the weight increases there is an approximately 4.5 lb during first trimester, 12 lb second trimester and 12 lb last trimester. Assure the pregnant woman that this a lot of weight gain can easily be lost afterwards. A. BARTHOLOMEW – at 20 weeks, FH approximates 20 cm at the level of the umbilicus. (view the drawing in this module) B. McDONALD’S RULE – FH in cm x 27 = AOG in months. C. EXPECTED DATE OF CONFINEMENT (EDC) LMP + 7 days – 3 months + 1 year THE GRAVIDA-PARA NOTATION G = Gravida or total number of pregnancies P = Para or outcomes of pregnancies T = full Term P = Premature  A = Abortion L = Living children OBSTERIC HISTORY TERMS are important in the conduction of maternal health history during the first prenatal visit GRAVIDA is the state of being pregnant and the total number of pregnancies including present pregnancy PARA is the number of pregnancies reaching the age of viability (the earliest age at which fetuses survive if they are born is generally accepted at 24 weeks or at the point a fetus weighs more than 500-600 grams ) whether infants were born alive or not. G-gravida; the current pregnancy T-term, number of full term infants born at 37 weeks age of gestation and beyond P-preterm, number of preterm infants born (infants born before 37 weeks) A-abortions, the number of pregnancies ending before 24 weeks L-living, it is the number of living children. t is a common practice for Filipina women to bind their abdomen tightly after pregnancy, believing that this practice helps the uterus to retract and gets the stomach back into shape. However, scientific suggests otherwise. Tying a cloth around one’s tummy can put pressure on the uterus, causing it to bleed. It can also lead to further complications, especially if you’ve undergone C-section. This myth has many variations, with some claiming that bananas lead to regular twins while others insist on Siamese twins, which is a serious condition wherein twins are born with part of their bodies joined together. However this myth has no scientific basis, as twins development happens because of genes. Usog is an age-old Filipino superstition. The belief states that discomfort (fever, bloating, nausea/vomiting) is brought to the baby by a stranger or visitor who is said to have an evil eye. A simple greetings from a visitor is said to be enough to cause this curse. To counter the curse, the stranger would need to say “pwera usog” while licking his thumb and applying saliva while tracing a cross on the infant’s forehead. Despite having no scientific proof regarding the occurrences of usog, many superstitious Filipinos believe in the practice to this date. Usog is also believe to be applicable to pregnant women. You have been told that whatever you eat you need to eat for two. You are eating for two, but do understand the other person you are eating for is too small, so unfortunately being pregnant will not give you the excuse to double the calorie intake. Overeating and wrong food choices can lead to complications such as gestational diabetes and excessive weight gain, both of which can be harmful and can make labor more difficult. Slow heart rate means a baby boy and a fast heart rate means a baby girl. A normal fetal heart rate is between 120 to 160 beats per minute, although people think if it’s faster (usually above 140 bpm range) it’s a girl and if it’s slower is a boy, there is no evidence or scientific proof to support this theory. Moreover, stress-related changes in a pregnant woman’s heart rate and blood pressure , along with chronic anxiety, can affect the heart rate of her developing Some pregnant women may avoid eating black foods to avoid the birth of an infant with a dark skin tone. Some pregnant women may place great emphasis on being tidy and beautiful, believing that these practices will influence the beauty of their child. Pregnant women should not wear a necklace or wrap a towel around her neck. It supposedly will cause the baby to suffer from “cord coil”. It is true that the umbilical cord can wrap itself around your baby’s leg or neck especially in your first and second trimester, it happens because of the constant movement the baby made, but it should not be a cause for concern. Labor is the series of events by which uterine contractions and abdominal pressure expel a fetus and placenta from the uterus. Regular contractions cause progressive dilatation of the cervix and create sufficient muscular uterine force to allow a baby to be pushed out into the extrauterine world. Labor represents a time of change as it is both an ending and a beginning for the woman, her fetus, and her family (Archie & Roman, 2013).