Anatomy and Physiology of the Reproductive System PDF

ANATOMY AND PHYSIOLOGY OF THE REPRODUCTIVE SYSTEM Normal testes feel ﬁrm, smooth, and egg-shaped. The epididymis Although the structures of the female and male reproductive (the tube that carries sperm away from the testes) can be palpated systems di6er greatly in appearance and function, they are as a ﬁrm swelling on the superior aspect of the testes. homologs—that is, they arise from the same or matched embryonic origin. Gynecology is the study of the female Penis. The penis is composed of three cylindrical masses of reproductive organs, while andrology is the study of the male erectile tissue in the penis shaft: two termed the corpus reproductive organs. cavernosa, and a third termed the corpus spongiosum. The urethra passes through these layers of erectile tissue, making the Male Reproductive System penis serve as the outlet for both the urinary and the reproductive The male reproductive system consists of external and internal tracts in men. With sexual excitement, nitric oxide is released from divisions (Fig. 5.2). the endothelium of blood vessels. This results in dilation of blood vessels and an increase in blood ﬂow to the arteries of the penis (engorgement). The ischiocavernosus muscle at the base of the penis then contracts, trapping both venous and arterial blood in the three sections of erectile tissue and leading to distention and erection of the penis. The penile artery, a branch of the pudendal artery, provides the blood supply for the penis. Penile erection is stimulated by parasympathetic nerve innervation. Male Internal Structures The male internal reproductive organs are the epididymis, the vas deferens, the seminal vesicles, the ejaculatory ducts, the prostate gland, the urethra, and the bulbourethral glands (see Fig. 5.2). Epididymis. The seminiferous tubule of each testis leads to a tightly coiled tube, the epididymis, which is responsible for Male External Structures conducting sperm from the tubule to the vas deferens, the next step in the passage to the outside. Because each epididymis is so Scrotum. The scrotum is a rugated, skin-covered, muscular tightly coiled, its length is extremely deceptive: it is actually over pouch suspended from the perineum. Its functions are to support 20 ft long. Some sperm are stored in the epididymis, and a portion the testes and to help regulate the temperature of sperm. In very of the alkaline ﬂuid that will surround sperm at maturity (semen, cold weather, the scrotal muscle contracts to bring the testes or seminal ﬂuid that contains a basic sugar and mucin, a form of closer to the body; in very hot weather, or the presence of fever, the protein) is produced by the cells lining the epididymis. muscle relaxes, allowing the testes to fall away from the body. In this way, the temperature of the testes can remain as even as Sperm are immobile and incapable of fertilization as they pass or possible to promote the production and viability of sperm. are stored at the epididymis level. It takes at least 12 to 20 days for them to travel the length of the epididymis and 64 days for them to Testes. The testes are two ovoid glands in the scrotum, 2 to 3 cm reach maturity. This is one reason that aspermia (absence of wide. Each testis is encased by a protective white ﬁbrous capsule sperm) and oligospermia (20 million sperm/mL) are problems that composed of several lobules, each containing interstitial cells do not appear to respond immediately to therapy but rather only (Leydig’s cells) and a seminiferous tubule. Seminiferous tubules after 2 months. produce spermatozoa. Leydig’s cells are responsible for the production of testosterone. Vas Deferens (Ductus Deferens). The vas deferens is an Testes in a fetus ﬁrst form in the pelvic cavity. They descend into additional hollow tube surrounded by arteries and veins and the scrotal sac late in intrauterine life (about the 34th to 38th protected by a thick ﬁbrous coating. It carries sperm from the week). Because this descent occurs so late in pregnancy, many epididymis through the inguinal canal into the abdominal cavity, male preterm infants are born with undescended testes. These where it ends at the seminal vesicles and the ejaculatory ducts. infants need to be monitored closely to see that the testes Sperm mature as they pass through the vas deferens. They are still descend when the infant reaches what would have been the 34th not mobile at this point, however, probably because of the fairly to 38th week of gestational age because testicular descent does acidic medium of the semen produced at this level. The blood not occur as readily in extrauterine life as it does in utero. Testes vessels and vas deferens together are referred to as the spermatic that remain in the pelvic cavity may not produce viable sperm and cord. A varicocele, or a varicosity of the internal spermatic vein, are associated with a 4 to 7 times higher incidence of testicular was once thought to contribute to male subfertility by causing cancer (Ellsworth, 2009). congestion with increased warmth in the testes, but this appears to actually make little di6erence (Evers & Collins, 2009). Although spermatozoa are produced in the testes, they reach Vasectomy (severing of the vas deferens to prevent the passage of maturity, surrounded by semen, in the external structures through sperm) is a popular means of male birth control (Cook et al., a complex sequence of regulatory events. First, the hypothalamus 2009). releases GnRH, which inﬂuences the anterior pituitary gland to release FSH and LH. FSH is then responsible for the release of Seminal Vesicles. The seminal vesicles are two convoluted androgen-binding protein (ABP). LH is responsible for the release pouches that lie along the lower portion of the posterior surface of of testosterone. ABP binding of testosterone promotes sperm the bladder and empty into the urethra by way of the ejaculatory formation. As the amount of testosterone increases, a feedback ducts. These glands secrete a viscous alkaline liquid that has a e6ect on the hypothalamus and the anterior pituitary gland is high sugar, protein, and prostaglandin content. Sperm become created that slows the production of FSH and LH and ultimately increasingly motile with this added ﬂuid because it surrounds decreases or regulates sperm production. them with nutrients and a more favorable pH. In most males, one testis is slightly larger than the other and is Ejaculatory Ducts. The two ejaculatory ducts pass through the suspended slightly lower in the scrotum than the other (usually the prostate gland and join the seminal vesicles to the urethra. left one). Because of this, testes tend to slide past each other more readily on sitting or muscular activity, and there is less possibility Prostate Gland. The prostate is a chestnut-sized gland that lies of trauma to them. Spermatozoa do not survive at a temperature just below the bladder. The urethra passes through the center of it, as high as that of the body; however, the location of the testes like the hole in a doughnut. The prostate gland secretes a thin, outside the body, where the temperature is approximately 1° F alkaline ﬂuid. When added to the secretion from the seminal lower than body temperature, protects sperm survival (McCance vesicles and the accompanying sperm from the epididymis, this & Huether, 2007). alkaline ﬂuid further protects sperm from being immobilized by the naturally low pH level of the urethra. In middle life, many men develop benign hypertrophy of the prostate. This swelling interferes with both fertility and urination. A benign condition can the distal vagina. Both glands' secretions help lubricate the be relieved by medical therapy or surgery but needs to be external genitalia during coitus. The alkaline pH of their secretions di6erentiated from prostate cancer (Parsons, 2007). helps to improve sperm survival in the vagina. Bulbourethral Glands. Two bulbourethral or Cowper’s glands lie The fourchette is the ridge of tissue formed by the posterior joining beside the prostate gland and empty via short ducts into the of the two labia minora and the labia majora. This is the structure urethra. Like the prostate gland and seminal vesicles, they secrete that is sometimes cut (episiotomy) during childbirth to enlarge the an alkaline ﬂuid that helps counteract the acid secretion of the vaginal opening. urethra and ensures the safe passage of spermatozoa. Semen, therefore, is derived from the prostate gland (60%), the seminal Posterior to the fourchette is the perineal muscle or the perineal vesicles (30%), the epididymis (5%), and the bulbourethral glands body. Because this is a muscular area, it is easily stretched during (5%). childbirth to allow for enlargement of the vagina and passage of the fetal head. Many exercises suggested for pregnancy (such as Urethra. The urethra is a hollow tube leading from the base of the Kegel’s, squatting, and tailor-sitting) are aimed at making the bladder, which, after passing through the prostate gland, perineal muscle more ﬂexible to allow easier expansion during continues to the outside through the shaft and glans of the penis. birth without tearing of this tissue. It is approximately 8 in (18 to 20 cm) long. Like other urinary tract structures, it is lined with mucous membrane. The hymen is a tough but elastic semicircle of tissue that covers the opening to the vagina in childhood. It is often torn during the Female Reproductive System time of ﬁrst sexual intercourse. However, because of the use of The female reproductive system, like the male system, has both tampons and active sports participation, many girls who have not external and internal components (Anderson & Genadry, 2007). had sexual relations do not have intact hymens at the time of their ﬁrst pelvic examination. Occasionally, a girl has an imperforate Female External Structures hymen, or a hymen so complete that it does not allow for passage The structures that form the female external genitalia are termed of menstrual blood from the vagina or for sexual relations until it is the vulva (from the Latin word for “covering”) and are illustrated in surgically incised (Dane et al., 2007). Figure 5.4. Female Internal Structures Female internal reproductive organs (Fig. 5.5) are the ovaries, the fallopian tubes, the uterus, and the vagina. Mons Veneris. The mons veneris is a pad of adipose tissue located over the symphysis pubis, the pubic bone joint. It is covered by a triangle of coarse, curly hairs. The purpose of the mons veneris is to protect the junction of the pubic bone from trauma. Ovaries. The ovaries are approximately 4 cm long by 2 cm in diameter and approximately 1.5 cm thick, or the size and shape of Labia Minora. Just posterior to the mons veneris spread two almonds. They are grayish-white and appear pitted or with minute hairless folds of connective tissue, the labia minora. Before indentations on the surface. The function of the two ovaries (the menarche, these folds are fairly small; by childbearing age, they female gonads) is to produce, mature, and discharge ova (the egg are ﬁrm and full; after menopause, they atrophy and again become cells). In the process, the ovaries produce estrogen and much smaller. Normally the folds of the labia minora are pink; the progesterone and initiate and regulate menstrual cycles. internal surface is covered with mucous membrane, and the external surface with skin. The area is abundant with sebaceous Division of Reproductive Cells (Gametes). At birth, each ovary glands, so localized sebaceous cysts may occur here contains approximately 2 million immature ova (oocytes), which were formed during the ﬁrst 5 months of in- intrauterine life. Labia Majora. The labia majora are two folds of adipose tissue Although these cells have the unique ability to produce a new covered by loose connective tissue and epithelium that are individual, they contain the usual components of cells: a cell positioned lateral to the labia minora. Covered by pubic hair, the membrane, an area of clear cytoplasm, and a nucleus containing labia majora serve as protection for the external genitalia and the chromosomes. distal urethra and vagina. They are fused anteriorly but separated posteriorly. Trauma to the area, such as occurs from childbirth or Maturation of Oocytes. Each oocyte lies in the ovary surrounded rape, can lead to extensive edema formation because of the by a protective sac, or thin layer of cells, called a primordial looseness of the connective tissue base. follicle. Between 5 and 7 million ova form in utero. The majority never develop beyond the primitive state and atrophy so that by Other External Organs. The vestibule is the ﬂattened, smooth birth, only 2 million are present. By age 7 years, only approximately surface inside the labia. The openings to the bladder (the urethra) 500,000 are present in each ovary; by 22 years, there are and the uterus (the vagina) both arise from the vestibule. The approximately 300,000; and by menopause, none are left (all have clitoris is a small (approximately 1 to 2 cm), rounded organ of either matured or atrophied). “The point at which no functioning erectile tissue at the forward junction of the labia minora. It is oocytes remain in the ovaries” is one deﬁnition of menopause. covered by a fold of skin, the prepuce. The clitoris is sensitive to touch and temperature and is the center of sexual arousal and Fallopian Tubes. The fallopian tubes arise from each upper corner orgasm in a woman. The arterial blood supply for the clitoris is of the uterine body and extend outward and backward until each plentiful. When the ischiocavernosus muscle surrounding it opens at its distal end, next to an ovary. Fallopian tubes are contracts with sexual arousal, the venous outﬂow for the clitoris is approximately 10 cm long in a mature woman. Their function is to blocked, leading to clitoral erection. convey the ovum from the ovaries to the uterus and to provide a place for fertilization of the ovum by sperm. Two Skene’s glands (paraurethral glands) are located just lateral Although a fallopian tube is a smooth, hollow tunnel, it is to the urinary meatus, one on each side. Their ducts open into the anatomically divided into four parts. The most proximal division, urethra. Bartholin’s glands (vulvovaginal glands) are located just the interstitial portion, is that part of the tube within the uterine lateral to the vaginal opening on both sides. Their ducts open into wall. This portion is only about 1 cm in length; the lumen of the tube is only 1 mm in diameter at this point. The isthmus is the next The endometrium layer of the uterus is important for menstrual distal portion. It is approximately 2 cm in length and, like the function. It is formed by two layers of cells. The layer closest to the interstitial tube, is extremely narrow. This is the tube portion cut or uterine wall, the basal layer, remains stable and uninﬂuenced by sealed in a tubal ligation or tubal sterilization procedure. The hormones. In contrast, the inner glandular layer is greatly ampulla is the third and also the longest part of the tube. It is inﬂuenced by both estrogen and progesterone. It grows and approximately 5 cm in length. It is in this portion that fertilization becomes so thick and responsive each month under the inﬂuence of an ovum usually occurs. The infundibular portion is the most of estrogen and progesterone that it is capable of supporting a distal segment of the tube. It is approximately 2 cm long and is pregnancy. If pregnancy does not occur, this layer is shed as the funnel-shaped. The rim of the funnel is covered by ﬁmbria (small menstrual ﬂow. hairs) that help to guide the ovum into the fallopian tube. The myometrium serves the important function of constricting the tubal junctions and preventing regurgitation of menstrual blood into the tubes. It also holds the internal cervical os closed during pregnancy to prevent a preterm birth. When the uterus contracts at the end of pregnancy to expel the fetus, equal pressure is exerted at all points throughout the cavity because of its unique arrangement of muscle ﬁbers. After childbirth, this interlacing network of ﬁbers can constrict the blood vessels coursing through the layers, thereby limiting the loss of blood in the woman. Myomas, or benign ﬁbroid (leiomyoma) tumors, arise from the myometrium (McCance & Heuther, 2007). The perimetrium, or the outermost layer of the uterus, adds strength and support to the structure. Uterus. The uterus is a hollow, muscular, pear-shaped organ in the lower pelvis, posterior to the bladder and anterior to the rectum. Vagina. The vagina is a hollow, musculomembranous canal During childhood, it is approximately the size of an olive, and its located posterior to the bladder and anterior to the rectum. It proportions are reversed from what they are later (i.e., the cervix is extends from the cervix of the uterus to the external vulva. Its the largest portion of the organ; the uterine body is the smallest). function is to act as the organ of intercourse and to convey sperm When a girl reaches approximately 8 years of age, an increase in to the cervix so that sperm can meet with the ovum in the fallopian the size of the uterus begins. An adolescent is closer to 17 years tube. With childbirth, it expands to serve as the birth canal. old before the uterus reaches its adult size. This may contribute to the low-birth-weight babies typically born to adolescents younger Breasts than this age. The mammary glands, or breasts, form from ectodermic tissue early in utero. They then remain in a halted stage of development With maturity, a uterus is approximately 5 to 7 cm long, 5 cm wide, until a rise in estrogen at puberty produces a marked increase in and, in its widest upper part, 2.5 cm deep. In a nonpregnant state, size. The size increase occurs mainly because of an increase in it weighs approximately 60 g. The function of the uterus is to connective tissue plus fat deposition. The glandular tissue of the receive the ovum from the fallopian tube, provide a place for breasts, necessary for successful breastfeeding, remains implantation and nourishment, furnish protection to a growing undeveloped until the ﬁrst pregnancy begins. Boys may notice a fetus, and, at maturity of the fetus, expel it from a woman’s body. temporary increase in breast size at puberty, termed Anatomically, the uterus consists of three divisions: the body or gynecomastia. If boys are not prepared that this is a normal corpus, the isthmus, and the cervix. The body of the uterus is the change of puberty, they may be concerned that they are uppermost part and forms the bulk of the organ. The lining of the developing abnormally. The change is most evident in obese boys cavity is continuous with that of the fallopian tubes, which enter at (Ma & Ge6ner, 2008). its upper aspects (the cornua). During pregnancy, the body of the uterus is the portion of the structure that expands to contain the Milk glands of the breasts are divided by connective tissue growing fetus. The portion of the uterus between the points of partitions into approximately 20 lobes. All glands in each lobe attachment of the fallopian tubes is termed the fundus. The produce milk by acinar cells and deliver it to the nipple via a fundus is also the portion that can be palpated abdominally to lactiferous duct. The nipple has approximately 20 small openings determine the amount of uterine growth occurring during through which milk is secreted. An ampulla portion of the duct, pregnancy, to measure the force of uterine contractions during located just posterior to the nipple, serves as a reservoir for milk labor, and to assess that the uterus is returning to its nonpregnant before breastfeeding. state after childbirth. A nipple is composed of smooth muscle that is capable of erection The isthmus of the uterus is a short segment between the body on manual or sucking stimulation. It transmits sensations to the and the cervix. In the nonpregnant uterus, it is only 1 to 2 mm in posterior pituitary gland on stimulation to release oxytocin. length. During pregnancy, this portion also Oxytocin acts to constrict milk gland cells and push milk forward enlarges greatly to aid in accommodating the growing fetus. It is into the ducts that lead to the nipple. The skin surrounding the the portion of the uterus that is most commonly cut when a fetus nipples is darkly pigmented out to approximately 4 cm and is is born by a cesarean birth. termed the areola. The area appears rough on the surface because The cervix is the lowest portion of the uterus. It represents it contains many sebaceous glands called Montgomery’s approximately one-third of the total uterus size and is tubercles. approximately 2 to 5 cm long. Approximately half of it lies above the vagina and half extends into the vagina. Its central cavity is termed the cervical canal. The opening of the canal at the junction MENSTRUATION of the cervix and isthmus is the internal cervical os; the distal A menstrual cycle (a female reproductive cycle) is episodic uterine opening to the vagina is the external cervical os. The level of the bleeding in response to cyclic hormonal changes. The purpose of external os is at the level of the ischial spines (an important a menstrual cycle is to bring an ovum to maturity and renew a relationship in estimating the level of the fetus in the birth canal). uterine tissue bed that will be responsible for the ova’s growth should it be fertilized. The process allows for conception and Uterine and Cervical Coats. The uterine wall consists of three implantation of a new life. Because menarche may occur as early separate coats or layers of tissue: an inner one of mucous as 9 years of age, it is good to include health teaching information membrane (the endometrium), a middle one of muscle ﬁbers (the on menstruation to both school-age children and their parents as myometrium), and an outer one of connective tissue (the early as fourth grade as part of routine care. perimetrium). The length of menstrual cycles di6ers from woman to woman, but the average length is 28 days (from the beginning After an upsurge of LH from the pituitary, prostaglandins are of one menstrual ﬂow to the beginning of the next). It is not released and the graaﬁan follicle ruptures. The ovum is set free unusual for cycles to be as short as 23 days or as long as 35 days. from the surface of the ovary, a process termed ovulation. It is The length of the average menstrual ﬂow (termed menses) is 4 to swept into the open end of a fallopian tube. Teach women that 6 days, although women may have periods as short as 2 days or as ovulation occurs on approximately the 14th day before the onset long as 7 days (MacKay, 2009). of the next cycle, not necessarily at a cycle’s midpoint. Because periods are typically 28 days, making the 14th day the middle of Physiology of Menstruation the cycle, many women believe correctly that the midpoint of their Four body structures are involved in the physiology of the cycle is their day of ovulation. If their cycle is only 20 days long; menstrual cycle: the hypothalamus, the pituitary gland, the however, their day of ovulation would be day 6 (14 days from the ovaries, and the uterus. For a menstrual cycle to be complete, all end of the cycle). If a cycle is 44 days long, ovulation would occur four structures must contribute their part; the inactivity of any part on day 30, not day 22. results in an incomplete or ine6ective cycle (Fig. 5.12). After the ovum and the follicular ﬂuid have been discharged from the ovary, the cells of the follicle remain in the form of a hollow, empty pit. The FSH has done its work at this point and has now decreased in amount. The second pituitary hormone, LH, continues to rise in amount and acts on the follicle cells of the ovary. It inﬂuences the follicle cells to produce lutein, a bright yellow ﬂuid. Lutein is high in progesterone and contains some estrogen, whereas the follicular ﬂuid is high in estrogen with some progesterone. This yellow ﬂuid ﬁlls the empty follicle, which is then termed a corpus luteum (yellow body). The basal body temperature of a woman drops slightly (by 0.5° to 1° F) just before the day of ovulation because of the extremely low level of progesterone that is present at that time. It rises by 1° F on the day after ovulation because of the concentration of progesterone (which is thermogenic) that is present at that time. The woman’s temperature remains at this level until approximately day 24 of the menstrual cycle, when the progesterone level again decreases (McCance & Huether, 2007). Hypothalamus The release of GnRH (also called luteinizing hormone– releasing If conception (fertilization by a spermatozoon) occurs as the ovum hormone, or LHRH) by the hypothalamus initiates the menstrual proceeds down a fallopian tube and the fertilized ovum implants cycle. When the level of estrogen (produced by the ovaries) rises, on the endometrium of the uterus, the corpus luteum remains release of the hormone is repressed, and menstrual cycles do not throughout the major portion of the pregnancy (approximately 16 occur (the principle that birth control pills use to eliminate to 20 weeks). menstrual ﬂow). If conception does not occur, the unfertilized ovum atrophies after GnRH is transmitted from the hypothalamus to the anterior 4 or 5 days, and the corpus luteum (called a “false” corpus luteum) pituitary gland and signals the gland to begin pro- ducing the remains for only 8 to 10 days. As the corpus luteum regresses, it is gonadotropic hormones FSH and LH. Because production of gradually replaced by white ﬁbrous tissue, and the resulting GnRH is cyclic, menstrual periods also cycle. structure is termed a corpus albicans (white body). Figure 5.13 shows the times when ovarian hormones are secreted at peak Pituitary Gland levels during a typical 28-day menstrual cycle. Under the inﬂuence of GnRH, the anterior lobe of the pitu- itary gland (the adenohypophysis) produces two hormones that act on Uterus the ovaries to further inﬂuence the menstrual cycle: (a) FSH, a hormone that is active early in the cycle and is responsible for First Phase of Menstrual Cycle (Proliferative). Immediately after maturation of the ovum, and (b) LH, a hor- mone that becomes a menstrual ﬂow (which occurs during the ﬁrst 4 or 5 days of a most active at the midpoint of the cycle and is responsible for cycle), the endometrium, or lining of the uterus, is very thin, ovulation, or release of the mature egg cell from the ovary, and approximately one cell layer in depth. As the ovary begins to growth of the uterine lining during the second half of the menstrual produce estrogen (in the follicular ﬂuid, under the direction of the cycle. pituitary FSH), the endometrium begins to proliferate. This growth is very rapid and increases the thickness of the endometrium Ovary approximately eightfold. This increase continues for the ﬁrst half FSH and LH are called gonadotropic hormones because they of the menstrual cycle (from approximately day 5 to day 14). This cause growth (trophy) in the gonads (ovaries). Every month during half of a menstrual cycle is termed interchangeably the the fertile period of a woman’s life (from menarche to proliferative, estrogenic, follicular, or postmenstrual phase. menopause), one of the ovary’s primordial follicles is activated by FSH to begin to grow and mature. As it grows, its cells produce a Second Phase of Menstrual Cycle (Secretory). After ovulation, clear ﬂuid (follicular ﬂuid) that contains a high degree of estrogen the formation of progesterone in the corpus luteum (under the (mainly estradiol) and some progesterone. As the follicle reaches direction of LH) causes the glands of the uterine endometrium to its maximum size, it is propelled toward the surface of the ovary. become corkscrew or twisted in appearance and dilated with At full maturity, it is visible on the surface of the ovary as a clear quantities of glycogen (an elementary sugar) and mucin (a water blister approximately 0.25 to 0.5 inches across. At this stage protein). The capillaries of the endometrium increase in amount of maturation, the small ovum (barely visible to the naked eye, until the lining takes on the appearance of rich, spongy velvet. This approximately the size of a printed period), with its surrounding second phase of the menstrual cycle is termed the progestational, follicle membrane and ﬂuid, is termed a graaﬁan follicle. luteal, premenstrual, or se- cretory phase. By day 14 before the end of a menstrual cycle (the mid-point of a typical 28-day cycle), the ovum has divided by mitotic division into Third Phase of Menstrual Cycle (Ischemic). If fertilization does two separate bodies: a primary oocyte, which contains the bulk of not occur, the corpus luteum in the ovary begins to regress after 8 the cytoplasm, and a secondary oocyte, which contains so little to 10 days. As it regresses, the production of cytoplasm that it is not functional. The structure also has progesterone and estrogen decreases. With the withdrawal of accomplished its meiotic division, reducing its number of progesterone stimulation, the endometrium of the uterus be- gins chromosomes to the haploid (having only one member of a pair) a to degenerate (at approximately day 24 or day 25 of the cycle). The number of 23. capillaries rupture, with minute hemorrhages, and the endometrium sloughs o6. Fourth Phase of a Menstrual Cycle (Menses). Menses, or the menstrual ﬂow, is composed of: Blood from the ruptured capillaries Mucin from the glands Fragments of endometrial tissue The microscopic, atrophied, and unfertilized ovum Contrary to common belief, a menstrual ﬂow contains only approximately 30 to 80 mL of blood; if it seems like more, it is because of the accompanying mucus and endometrial shreds. The iron loss in a typical menstrual ﬂow is approximately 11 mg. This is enough loss that many women need to take a daily iron 1. Menstrual Phase (Days 1-5): supplement to prevent iron depletion during their menstruating o What happens: The uterine lining years. (endometrium) sheds, resulting in menstrual In women who are beginning menopause, menses may typically bleeding. Hormone levels (FSH and LH) are low. consist of a few days of spotting before a heavy ﬂow, or a heavy 2. Follicular Phase (Days 1-13): ﬂow followed by a few days of spotting, because progesterone o What happens: FSH stimulates follicle growth withdrawal is more sluggish or tends to “stair- case” rather than in the ovaries. As the follicle matures, it withdraw smoothly. produces estrogen, which causes the uterine lining to thicken in preparation for a possible pregnancy. 3. Ovulation (Day 14): Ovary and o What happens: A surge in LH triggers the Menstrual release of a mature egg from the ovary Cycle (ovulation). The egg is swept into the fallopian Summary: tube. 1. Ovary 4. Luteal Phase (Days 15-28): and o What happens: The empty follicle forms Follicle the corpus luteum, which secretes Development: progesterone to maintain the uterine lining. If o FSH and LH, called gonadotropic hormones, fertilization does not occur, hormone levels stimulate growth in the ovaries. drop, causing the uterine lining to shed, and the o Each month, FSH activates one primordial cycle restarts. follicle in the ovary to grow and mature, This is a general cycle based on 28 days. Some cycles may be producing estrogen and progesterone. At full shorter or longer, and ovulation can occur earlier or later. maturity, the follicle becomes a graaﬁan follicle. Cervix o By the 14th day of the menstrual cycle, the The mucus of the uterine cervix and the uterine body changes follicle undergoes mitotic each month during the menstrual cycle. During the ﬁrst half of the division and meiotic division, preparing the cycle, when hormone secretion from the ovary is low, cervical egg (ovum) for ovulation. mucus is thick and scant. Sperm survival in this type of mucus is o Ovulation occurs after an LH surge, where the poor. At the time of ovulation, when the estrogen level is high, graaﬁan follicle ruptures and releases the cervical mucus becomes thin and copious. Sperm penetration ovum into the fallopian tube. and survival during ovulation in this thin mucus are excellent. o Post-ovulation, LH stimulates the formation of the corpus luteum, which Women can analyze cervical mucus changes to help plan coitus produces progesterone and some estrogen. to coincide with ovulation if they want to increase their chance of 2. Hormonal Changes: becoming pregnant or plan to avoid coitus at the time of ovulation o Progesterone levels rise after ovulation, to prevent pregnancy. leading to an increase in basal body temperature. Fern Test. When high levels of estrogen are present in the body, as o If fertilization occurs, the corpus luteum they are just before ovulation, the cervical mucus forms fernlike supports pregnancy by producing hormones patterns caused by the crystallization of sodium chloride on for 16-20 weeks. If not, it degrades into mucus ﬁbers when it is placed on a glass slide and allowed to dry. a corpus albicans. This pattern is known as arborization or ferning. 3. Menstrual Cycle Phases: o Proliferative Phase (Days 5-14): Estrogen Spinnbarkeit Test. At the height of estrogen secretion, cervical stimulates the thickening of the endometrium. mucus becomes thin and watery and can be stretched into long o Secretory Phase (After strands. This stretchability is in contrast to its thick, viscous state Ovulation): Progesterone from the corpus when progesterone is the dominant hormone. Performing this test, luteum makes the endometrium glandular and known as spinnbarkeit, at the midpoint of a menstrual cycle is spongy to prepare for potential pregnancy. another way to demonstrate that high estrogen levels are being o Ischemic Phase: If no fertilization occurs, produced and, by implication, that ovulation is about to occur. A hormone levels drop, causing the woman can do this herself by stretching a mucus sample between endometrium to degenerate. thumb and ﬁnger, or it can be tested in an examining room by o Menses (Menstrual Flow): The endometrium smearing a cervical mucus specimen on a slide and stretching the sheds, accompanied by blood, mucus, and the mucus between the slide and coverslip. unfertilized ovum. Menstrual blood loss ranges from 30-80 mL. Education for Menstruation Menstruation marks the end of one cycle and the beginning of another. Menstruation education is essential for dispelling myths and promoting a positive view of menstruation. Teaching girls early helps them see it as a natural part of growing up rather than a burden. Educating boys is also important to foster an understanding of the female reproductive cycle and their role in planning or preventing conception. Proper education reduces menstrual discomfort, leading to fewer missed school days for girls. Menopause is the cessation of menstrual cycles, typically occurring between ages 40 and 55, with a mean age of 51.3 years. It marks the end of a woman’s ability to bear children. Perimenopause refers to the transitional period leading to menopause, while postmenopausal describes life after the ﬁnal menstrual period. Genetics and lifestyle factors, like smoking, can inﬂuence the age of menopause onset. (Baram & Basson, 2007). Physiological and Psychological E\ects: Menopause can cause hot ﬂashes, vaginal dryness, osteoporosis, and urinary incontinence due to reduced estrogen levels as the ovaries atrophy. (Freeman et al., 2007). Hot ﬂashes may occur 20-30 times daily, lasting 3-5 minutes, and can be relieved by sipping cold drinks or using hand fans. The psychological impact may arise from the end of childbearing, but education can help women understand that menopause can be a positive change, especially for those with no desire for more children or those su6ering from menstrual pain. Hormone Replacement Therapy (HRT): HRT was once widely used to reduce menopause symptoms and prevent cardiovascular issues. However, it is now used less due to potential risks, including endometrial cancer, stroke, and possibly breast cancer, with no proven beneﬁt for reducing cardiac risks or preventing osteoporosis. (Gabriel-Sanchez, et al., 2009). Pillitteri, Adele.Maternal and child health nursing : care of the childbearing and childrearing family/Adele Pillitteri.—6th ed. p. ; cm.

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