Physiology of Menstrual Cycle PDF

CARE OF MOTHER, CHILD, 01 T...

CARE OF MOTHER, CHILD, 01 T NRCM0107–LEC E R VILLANUEVA ADOLESCENT (LEC) M TOPIC 3: PHYSIOLOGY OF MENSTRUAL CYCLE FEMALE REPRODUCTIVE CYCLE FOLLICLE STIMULATING HORMONE (FSH) Refers to the regular and recurrent changes in the Triggered by FSHRF and low serum estrogen. secretion of anterior pituitary gland, ovary and It stimulates the development of several Graafian uterine endometrium that are designed to prepare follicles in the ovary and the production of the body for pregnancy. estrogen. It is often called menstrual cycle because menstruation provides a marker for each LUTEINIZING HORMONE (LH) beginning and end if pregnancy does not occur. The duration of cycle is about 28 days though it Triggered by low serum progesterone and LHRF. may range from 20-45 days. It stimulates corpus luteum to produce progesterone and some estrogen. During puberty, a weight of 95lbs or 43kgs, It is also the responsible for ovulation. triggers the initiation of menstrual cycle. OVARIES The ovary, known as the female gonads, produces estrogen during the first half of the cycle and progesterone during the second half of the cycle. ESTROGEN FSH stimulates the Graafian follicle to produce estrogen. Estrogen is metabolized by the liver and excreted BODY STRUCTURES in the urine. HYPOTHALAMUS There are actually three kinds of estrogen: The hypothalamus is the ultimate initiator of the o Estradiol menstrual cycle. o Estrone By secreting the Gonadotropin Releasing o Estriol Hormones (GnRH) it governs the ovary in the same manner. ESTRADIOL The GnRH are: Estradiol is the most potent. FOLLICLE STIMULATING HORMONE ESTRIOL RELEASING FACTOR (FSHRF) Estriol is the one found in urine. This hormone is triggered by low serum estrogen level, it stimulates the anterior pituitary gland to THE EFFECTS OF ESTROGEN release follicle stimulating hormone. These include: LUTEINIZING HORMONE RELEASING o Inhibit follicle stimulating hormone. o Estrogen is known as the "Hormone of FACTOR (LHRF) Women" because it is the hormone that This hormone is triggered by low serum stimulates the development of the female progesterone level, it stimulates anterior pituitary secondary characteristics such as the gland to release luteinizing hormone (LH). increased deposition of fat in certain areas of the body that gives a female shape, breast ANTERIOR PITUITARY GLAND growth, development of the female In response to the stimulation from the reproductive organs and pattern of hair hypothalamus and low serum estrogen and growth in the vulva. progesterone levels, the anterior pituitary gland releases the following gonadotropin hormones o Stimulate proliferation of cells in the (GH): endometrium resulting in endometrial thickening. MAGNO 1  TOPIC 3: PHYSIOLOGY OF MENSTRUAL CYCLE o Causes mucus to be thin, transparent, and MENARCHE highly stretchable. Menarche refers to the very first menstruation, an o Stimulates the growth of ductile structures of event that signifies the end of puberty and the the breasts. beginning of the reproductive years of a woman. o Menarche and menstruation. THE OVARIAN CYCLE PROGESTERONE TWO PHASES OF THE OVARIAN CYCLE LH stimulates the Corpus Luteum to produce FOLLICULAR PHASE (1–14 DAYS) progesterone. Varies Its byproduct, found in the urine, is known as The immature follicle (primordial follicle) matures Pregnanediol. as a result of FHS and small amount of LH. The effects of progesterone are: The blood levels of estradiol in blood stream o Thermogenic effect, increases basal body begin to rise and estradiol in turn acts negatively temperature. on the CNS at the hypothalamic-pituitary level by o Relaxes uterine muscles. inhibiting the release of additional FHS. o Promotes growth of the acini cells of the Consequently, the levels of FHS in circulating breasts. blood begins to fall. o Causes weight gain by promoting fluid Few days prior to ovulation, all but one follicle retention. that is destined to ovulate begin to regress or o Is thought to be the cause of Premenstrual degenerate (ATRESIA), forming atretic follicle. Syndrome (PMS). o Causes tingling sensation and feeling of GROWTH OF A FOLLICLE fullness in the breast before menstruation. It is characterized by: o Secretory changes in the endometrium: o Proliferation of granulose. - Stimulates endometrial glands to secrete o Formation of a capsule connective tissue mucin and glycogen in preparation for from the ovarian stroma around the follicle implantation. (consisting of a connective of an inner cellular layer, the theca interna, and outer PROSTAGLANDIN fibrous layer, the theca externa). Oxygenated fatty acids that are produced by cells o Completion of the first mitotic division with of endometrium. the formation of secondary oocyte. o Expulsion of the follicular content. PROSTAGLANDIN E (PGE) Relaxes smooth muscle, vasodilator. PROSTAGLANDIN F (PGF) Vasoconstrictor and increases contractility of arteries and muscle. UTERUS The changes that occur in the uterine endometrium are due to the influence of the ovarian hormones: o Estrogen o Progesterone The average age at which menarche occurs is 12 ANTRUM to 13 years, but the onset of menstruation may As the follicle develops, a cavity soon appears occur anytime between 9 to 17 years old separating the mass of proliferating cell into 2 depending on many conditions including parts. nutrition, heredity, and race. Often occurs between the appearance of pubic LIQUOR FOLLICULI and axillary hair, and approximately two after The cavity is filled with fluid believed to be Thelarche. secreted by the cells of the follicle. The first menstrual cycles are usually anovulatory, painless and irregular. MAGNO 2  TOPIC 3: PHYSIOLOGY OF MENSTRUAL CYCLE ZONA PELLUCIDA (OOLEMMA) The Corpus Luteum absorbs the Corpus Oocyte becomes pressed to one side of vesicular Hemorrhagicum. follicle and is separated from the surrounding Corpus luteum secretes large amount of layer of cells by a transparent membrane known progesterone and lesser amounts of estrogen. as the Zona Pellucida (Oolemma). If the ovum is fertilized and implants in the endometrium, the fertilized egg begins to secrete CUMULUS OOPHOROUS HCG which is needed to maintain corpus luteum. The corpus luteum provides progesterone to A mound of cells surrounding the oocyte projects maintain the pregnancy until the month the into the antrum. placenta takes over it. The follicle becomes distended by an If fertilization does not occur, within about a accumulation of fluid and moves outward to the week after ovulation, the Corpus Luteum begins surface of ovary. to degenerate, eventually becoming a connective Once a month, usually at the middle of 28-day tissue scar called Corpus Albicans (white scar). cycle, the process of ovulation occurs. With degeneration comes a decrease in estrogen and progesterone. CORONA RADIATA This allows for an increase in LH and FHS which The follicle ruptures and the secondary oocyte triggers the hypothalamus approximately 14 surrounded by a ring of granulose cells called days after ovulation (in a 28-day cycle) Corona Radiata slowly oozes out of the ovarian menstruation begins. surface. THECA EXTERNA Cause of rupture is the increase in distensibility and reduction in breaking strength of follicular wall. COLLAGENASE Due to the secretion of progesterone by follicular tissue which induces the production of an enzyme Collagenase. OVULATION OVULATION Normal process of discharging a mature ovum Ovulation is initiated by a steep rise in the release from an ovary approximately 14 + 2 days prior to of LH. onset of menses. It takes place following the very rapid growth of follicle as the sustained high level of estrogen SIGNS OF OVULATION falls and progesterone secretion begins. MITTELSCHMERZ Occasionally, ovulation is accompanied by mid- cycle pain (Mittelschmerz) which is caused by a Pain in the lower abdomen left at the side of the thick Tunica Albuginea or by a local peritoneal ovary that released the ovum. reaction to the following to the expelling of follicular content. SPINNBARKHEIT Characterized by cervical mucus that is thin, LUTEAL PHASE (15–28 DAYS) watery or transparent and highly stretchable. Fixed When dried and viewed under a microscope, the Begins when the ovum leaves its follicle. mucus reveals a fern pattern. Under the influence of LH, the corpus luteum develops from the ruptured follicle. AMOUNT OF CERVICAL MUCUS First, there is minimal hemorrhage into the INCREASES ruptured follicle, forming a blood clot (Corpus Hemorrhagicum). Then a cell of ruptured follicle undergoes INCREASE BASAL BODY TEMPERATURE alteration and creates a mass known as the (BBT) Corpus Luteum which becomes yellowish after 2- 0.3 to 0.6 °C, 24-48 hours after ovulation due to 3 days. the effect of progesterone. MAGNO 3  TOPIC 3: PHYSIOLOGY OF MENSTRUAL CYCLE MID–CYCLE SPOTTING Cervical mucosa pH increased from below 7–7.5 Maybe present at the time of ovulation. On exam, mucus shows ferning pattern. PEAK OF BLOOD LEVEL LH Estrogen peaks just before ovulation. Body temperature drops prior to ovulation then at 24-48hrs before ovulation, can be detected in ovulation BBT increase. urine test. Mittelschmerz and midcycle spotting occurs. MENSTRUATION It is cyclic uterine in response to cyclic hormonal changes. Occurs when the ovum is not fertilized and begins about 14 days after ovulation in 28 day cycle. Average duration of menses 2-8 days Average blood loss 25 – 60 ml, average 30 ml Average iron loss 0.4 – 1 mg/day. MENSES/ MENSTRUAL FLOW Menstrual discharge is composed of blood mixed with cervical and and vaginal secretions, bacteria, mucus, leukocytes and other cellular debris. MENARCHE Refers to very first menstruation. SECRETORY PHASE (14–26 DAYS) Average age of onset is 12 – 13 years but may Also called pre-gestational, luteal phase. occur any time between 9 -17 years old. After release of ovum, estrogen level drop, Ovulation does not occur in early menstrual progesterone level increases cycle (anovulatory cycles) which are irregular in Endometrium goes light cellular growth, glands frequency, amount of flow and duration. hypertrophy and takes on coiled and tortus appearance which further thickens endometrium. FACTORS AFFECTING MENSTRUATION CYCLE Glands secrete small quantitative of Emotional factors endometrium fluid in preparation for fertilized o Stress ovum. o Anxiety Vascularity of the entire uterus increase Physical factors providing a nourishing bed for fertilized ovum. Environmental factors If implantation occurs the endometrium under the influences of progesterone continue to develop 4 PHASES OF THE MENSTRUAL CYCLE and become thicker, fertilize ovum begins to MENSTRUAL PHASE (1–5 DAYS) secrete HCG and maintain corpus luteum. Unless the ovum is fertilized, the corpus luteum is short lived. The endometrial lining is destroyed and is rebuilt for the next possible implantation. Some endometrial areas are shed while others remain. Estrogen level is low Viscous and opaque PROLIFERATIVE PHASE (6–14TH) Otherwise known as follicular, estrogenic, post menstrual phase. Enlargement of endometrial glands which becomes twisted and longer in response to increase estrogen. Blood vessels become prominent and dilated. Endometrium increases in thickness to eightfold. Cervical mucus shows increase elasticity. MAGNO 4  TOPIC 3: PHYSIOLOGY OF MENSTRUAL CYCLE ISCHEMIC PHASE (27–28 DAYS) EDUCATION ABOUT MENSTRUATION Also called premenstrual phase. That deodorants and increased absorbency that If implantation does not occur, corpus luteum manufacturers have added to sanitary napkins decrease in function activity, degenerative and tampons may prove harmful. changes are observe in uterine endometrium and Bathing/perineal care ischemic phase begins. Wipe from front to back. Both estrogen and progesterone level falls. Spinal arteries undergo vasoconstriction. ASSOCIATED MENSTRUAL CONDITION Endometrium becomes pale. HYPOMENORRHEA Small blood vessels rupture. Short duration of menstrual flow. Blood escapes into uterine stromal cells. HYPERMENORRHEA Long duration of menstrual flow. OLIGOMENORRHEA Irregular interval more than 40 days. POLYMENORRHEA Regular, irregular, interval of less than 22 days. MENORRHAGIA Excessive amount, duration, regular CHARACTERISTICS OF A NORMAL MENSTRUAL CYCLE METRORRHAGIA BEGINNING (MENARCHE) Normal amount, irregular Average age ranges from 9 -17 years. MENOMETRORRHAGIA INTERVAL BETWEEN CYCLES Excessive amount, duration, irregular Average 28 days, may vary from 23 – 35 days. INTERMENSTRUAL BLEEDING DURATION OF MENSTRUAL FLOW Occurs between regular menstrual cycle. Average 2-7 days, ranges from 1 -9 days. AMENORRHEA AMOUNT OF MENSTRUAL FLOW Absence of menses may be due to: Difficult to estimate o Hypothalamic dysfunction Average is 30 – 80 ml /menstrual period o Pituitary dysfunction Saturating a pad in less than one hour or o Ovarian failure consuming more than 8 perineal pads a day is o Anatomic abnormalities considered heavy flow. DYSMENORRHEA COLOR OF MENSTRUAL FLOW Painful menstruation Dark red A combination of: PRIMARY o Blood Cramps with no underlying disease, uterine o Mucus ischemia, normally disappears after first o Endometrial cells pregnancy. ODOR SECONDARY Similar to that of marigolds. Associated with diseases like endometritis, PID, AVERAGE IRON LOSS cysts. During menstruation is 12 – 29 mgs PREMENSTRUAL SYNDROME Symptom complex associated with the luteal NOTE phase of the menstrual cycle, occurs between A woman loses 10 -20 liters of blood in her entire ovulation and onset of menses. life due to menstruation. MAGNO 5  TOPIC 3: PHYSIOLOGY OF MENSTRUAL CYCLE MENOPAUSE PSYCHOLOGIC CHANGES ASSOCIATED WITH Refers to the time when menses cease, marking MENOPAUSE the end of reproductive abilities. Mood Swings Also called Climacteric or change of life. Depression Despair PREMATURE MENOPAUSE Irritability Occurs before age of 45, can be caused by: o Surgical removal of ovaries (oophorectomy) o Removal of uterus (hysterectomy) o Radiation PERIMENOPAUSE Period of time prior to menopause during which the woman move from normal ovulatory cycle to MANAGEMENT OF PATIENTS EXPERIENCING cessation of menstruation. MENOPAUSAL SIGNS AND SYMPTOMS Characterized by decreased ovarian function and HORMONE REPLACEMENT THERAPY unstable endocrine physiology, and highly variable, unpredicted hormone profile. PREVENTION AND TREATMENT OF OSTEOPOROSIS PHYSICAL CHANGES ASSOCIATED WITH BIPHOSPHONATES MENOPAUSE Calcium regulators CHANGES IN THE REPRODUCTIVE SYSTEM SELECTIVE ESTROGEN RECEPTION MODULATORS VASOMOTOR CHANGES RALOXIFENE (EVISTA) HOT FLASHES Acts like estrogen by protecting the body against Feeling of heat arising from chest and spreading osteoporosis but does not stimulate uterine or to neck and face usually accompanied by: breast tissue. o Night sweats o Dizzy spells SALMON CALCITONIN o Palpitations It is a calcium regulator that may inhibit bone o Weakness loss and is approved for use to treat osteoporosis in women who are five years post menopause. CHANGES IN MUSCULOSKELETAL SYSTEM AND SKIN ALTERNATIVE MEDICINE OSTEOPENIA DIET Low bone mass PHYTOESTROGEN Naturally occurring plant sterols that have an OSTEOPOROSIS estrogen like effect. Bone mass decrease below critical point. Example: o Ginseng WRINKLES o Agnus castus It is due to decrease protein from skin and o Beth root supportive tissues. o Black cohosh o Dong quai o Fenu Greek WEIGHT GAIN o Licorice o Red sage CHANGES IN CARDIOVASCULAR SYSTEM o Sarsaparilla o Wild Mexican yam NEUROLOGIC CHANGES ASSOCIATED WITH o Soy beans MENOPAUSE Alzheimer associated with high cholesterol level. SCREENING FOR OSTEOPOROSIS, CV DISEASE, AND CA OSTEOPOROSIS DEXA (Dual Energy X-ray Absorptionmetry) MAGNO 6  TOPIC 3: PHYSIOLOGY OF MENSTRUAL CYCLE CV–BP, BLOOD CHOLESTEROL CANCER Mammogram Pap smear Pelvic exam Digital rectal exam LIFESTYLE MODIFICATION KIDNEY STONE PREVENTION Liberal fluid intake 3000 ml per day PREVENT CV DISEASE PREVENT CA CONTRACEPTION Possible to get pregnant, 12 months after the last menses. LUBRICANTS FOR DYSPAREUNIA HOT FLASHES Avoid hot environment, cooling technique. MAGNO 7