The Nursing Role in Preparing Families for Childbearing and Childrearing PDF

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reproductive system human development childbearing nursing

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This document details the nursing role in preparing families for childbearing and childrearing. It covers topics like outcome evaluation, reproductive development, and the role of hormones. The document also includes information on intrauterine development and pubertal development.

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86 UNIT 2 The Nursing Role in Preparing Families for Childbearing and Childrearing Men who have sex with men (MWM) or women who form the urethra; in females, with no testosterone present, the have sex with women (WWW) or others with alternative urogen...

86 UNIT 2 The Nursing Role in Preparing Families for Childbearing and Childrearing Men who have sex with men (MWM) or women who form the urethra; in females, with no testosterone present, the have sex with women (WWW) or others with alternative urogenital fold remains open to form the labia minora; what lifestyles usually reveal their sexual orientation to health would be formed as scrotal tissue in the male becomes the labia care providers because they want help dealing with friends majora in the female. If, for some reason, testosterone secretion or family who are having difficulty accepting their gender is halted in utero, a chromosomal male could be born with fe- identity. In addition to support, provide health education male-appearing genitalia. If a woman should be prescribed a that addresses potential concerns of clients with all form of testosterone during pregnancy or if the woman, be- lifestyles. For example, include a discussion about anal or cause of a metabolic abnormality, produces a high level of oral-genital sex practices when presenting information on testosterone, a chromosomal female could be born with male- safer sex. appearing genitalia (Torresani & Biason-Lauber, 2007). Outcome Evaluation Pubertal Development Evaluation in the area of reproductive health must be on- going, because health education needs change with cir- Puberty is the stage of life at which secondary sex changes cumstances and increased maturity. For example, the begin. These changes are stimulated when the hypothalamus needs of a woman at the beginning of a pregnancy may be synthesizes and releases gonadotropin-releasing hormone totally different from her needs at the end. (GnRH), which in turn triggers the anterior pituitary to begin How people feel about themselves sexually may have a the release of follicle-stimulating hormone (FSH) and luteiniz- great deal to do with how quickly they recover from an ill- ing hormone (LH). FSH and LH initiate the production of ness, how quickly they are ready to begin self-care after androgen and estrogen, which in turn initiate secondary sex childbirth, or even how well motivated they are as adoles- characteristics, the visible signs of maturity. Girls are beginning cents to accomplish activities in other life phases that de- dramatic development and maturation of reproductive organs pend on being sure of sexuality or gender role. at earlier ages than ever before (9 to 12 years) (McDowell, Examples of expected outcomes are: Brody, & Hughes, 2007). Although the mechanism that initi- ates this dramatic change in appearance is not well understood, Client states he is taking precautions to prevent con- the hypothalamus, under the direction of the central nervous tracting an STI. system, may serve as a gonadostat or regulation mechanism set Client states she is better able to manage symptoms of to “turn on” gonad functioning at this age. Although it is not premenstrual dysphoric syndrome. proved, the theory is that a girl must reach a critical weight of Couple states they have achieved a mutually satisfying approximately 95 lb (43 kg) or develop a critical mass of body sexual relationship. fat before the hypothalamus is triggered to send initial stimu- Client states he is ready to tell family about MWM lation to the anterior pituitary gland to begin the formation of gender identity. ❧ gonadotropic hormones. Studies of female athletes and girls with anorexia nervosa reveal that a lack of fat can delay or halt menstruation. The phenomenon of why puberty occurs is even less well understood in boys. REPRODUCTIVE DEVELOPMENT Reproductive development and change begin at the moment Role of Androgen of conception and continue throughout life. Androgenic hormones are the hormones responsible for mus- cular development, physical growth, and the increase in se- Intrauterine Development baceous gland secretions that causes typical acne in both boys and girls. In males, androgenic hormones are produced by The sex of an individual is determined at the moment of con- the adrenal cortex and the testes; in females, by the adrenal ception by the chromosome information supplied by the par- cortex and the ovaries. ticular ovum and sperm that joined to create the new life. The level of the primary androgenic hormone, testos- A gonad is a body organ that produces the cells necessary for terone, is low in males until puberty (approximately age 12 to reproduction (the ovary in females, the testis in males). At ap- 14 years). At that time, testosterone levels rise to influence the proximately week 5 of intrauterine life, primitive gonadal tissue further development of the testes, scrotum, penis, prostate, is already formed. In both sexes, two undifferentiated ducts, and seminal vesicles; the appearance of male pubic, axillary, the mesonephric (wolffian) and paramesonephric (müllerian) and facial hair; laryngeal enlargement and its accompanying ducts, are present. By week 7 or 8, in chromosomal males, voice change; maturation of spermatozoa; and closure of this early gonadal tissue differentiates into primitive testes and growth in long bones. begins formation of testosterone. Under the influence of testos- In girls, testosterone influences enlargement of the labia terone, the mesonephric duct begins to develop into the male majora and clitoris and formation of axillary and pubic hair. reproductive organs, and the paramesonephric duct regresses. If This development of pubic and axillary hair because of an- testosterone is not present by week 10, the gonadal tissue dif- drogen stimulation is termed adrenarche. ferentiates into ovaries, and the paramesonephric duct develops into female reproductive organs. All of the oocytes (cells that Role of Estrogen will develop into eggs throughout the woman’s mature years) are already formed in ovaries at this stage (MacKay, 2009). When triggered at puberty by FSH, ovarian follicles in fe- At about week 12, the external genitals develop. In males, males begin to excrete a high level of the hormone estrogen. under the influence of testosterone, penile tissue elongates and This hormone is actually not one substance but three the urogenital fold on the ventral surface of the penis closes to compounds (estrone [E1], estradiol [E2], and estriol [E3]). CHAPTER 5 The Nursing Role in Reproductive and Sexual Health 87 It can be considered a single substance, however, in terms ANATOMY AND PHYSIOLOGY of action. The increase in estrogen levels in the female at puberty in- OF THE REPRODUCTIVE SYSTEM fluences the development of the uterus, fallopian tubes, and Although the structures of the female and male reproductive vagina; typical female fat distribution and hair patterns; systems differ greatly in both appearance and function, they breast development; and an end to growth because it closes are homologues—that is, they arise from the same or the epiphyses of long bones. The beginning of breast devel- matched embryonic origin (Fig. 5.1). The study of the fe- opment is termed thelarche. male reproductive organs is called gynecology. Andrology is the study of the male reproductive organs. Secondary Sex Characteristics Adolescent sexual development is categorized into stages Male Reproductive System (Tanner, 1990). There is wide variation in the time required for adolescents to move through these developmental stages; The male reproductive system consists of both external and however, the sequential order is fairly constant. In girls, pu- internal divisions (Fig. 5.2). bertal changes typically are manifest as: Male External Structures 1. Growth spurt 2. Increase in the transverse diameter of the pelvis External genital organs of the male include the testes (which 3. Breast development are encased in the scrotal sac) and the penis. 4. Growth of pubic hair 5. Onset of menstruation Scrotum. The scrotum is a rugated, skin-covered, muscular 6. Growth of axillary hair pouch suspended from the perineum. Its functions are to sup- 7. Vaginal secretions port the testes and to help regulate the temperature of sperm. In very cold weather, the scrotal muscle contracts to bring the The average age at which menarche (the first menstrual pe- testes closer to the body; in very hot weather, or in the pres- riod) occurs is 12.4 years (McDowell et al., 2007). It may occur ence of fever, the muscle relaxes, allowing the testes to fall as early as age 9 or as late as age 17, however, and still be within away from the body. In this way, the temperature of the testes a normal age range. Irregular menstrual periods are the rule can remain as even as possible to promote the production and rather than the exception for the first year. Menstrual periods viability of sperm. do not become regular until ovulation consistently occurs with them (menstruation is not dependent on ovulation), and this Testes. The testes are two ovoid glands, 2 to 3 cm wide, that does not tend to happen until 1 to 2 years after menarche. This lie in the scrotum. Each testis is encased by a protective is one reason why estrogen-based oral contraceptives are not white fibrous capsule and is composed of several lobules, commonly recommended until a girl’s menstrual periods have with each lobule containing interstitial cells (Leydig’s cells) become stabilized or are ovulatory (to prevent administering a and a seminiferous tubule. Seminiferous tubules produce compound to halt ovulation before it is firmly established). spermatozoa. Leydig’s cells are responsible for the produc- In boys, production of spermatozoa does not begin in in- tion of testosterone. trauterine life as does the production of ova, nor are sperma- Testes in a fetus first form in the pelvic cavity. They de- tozoa produced in a cyclic pattern as are ova; rather, they are scend, late in intrauterine life (about the 34th to 38th week), produced in a continuous process. The production of ova into the scrotal sac. Because this descent occurs so late in preg- stops at menopause (the end of the fertile period in females). nancy, many male preterm infants are born with undescended In contrast, sperm production continues from puberty testes. These infants need to be monitored closely to see that throughout the male’s life. the testes do descend when the infant reaches what would have Secondary sex characteristics of boys usually occur in the been the 34th to 38th week of gestational age, because testicu- order of: lar descent does not occur as readily in extrauterine life as it does in utero. Testes that remain in the pelvic cavity may not 1. Increase in weight produce viable sperm and are associated with a 4 to 7 times 2. Growth of testes higher incidence of testicular cancer (Ellsworth, 2009). 3. Growth of face, axillary, and pubic hair Although spermatozoa are produced in the testes, they 4. Voice changes reach maturity, surrounded by semen, in the external struc- 5. Penile growth tures through a complex sequence of regulatory events. First, 6. Increase in height the hypothalamus releases GnRH, which in turn influences 7. Spermatogenesis (production of sperm) the anterior pituitary gland to release FSH and LH. FSH is then responsible for the release of androgen-binding protein ✔Checkpoint Question 5.1 (ABP). LH is responsible for the release of testosterone. ABP Suzanne Matthews tells you she used to worry because her binding of testosterone promotes sperm formation. As the breasts developed at puberty later than those of most of her amount of testosterone increases, a feedback effect on the hy- friends. Breast development is termed: pothalamus and anterior pituitary gland is created that slows the production of FSH and LH and ultimately decreases or a. Adrenarche regulates sperm production. b. Mamarche In most males, one testis is slightly larger than the other c. Thelarche and is suspended slightly lower in the scrotum than the other d. Menarche (usually the left one). Because of this, testes tend to slide past 88 UNIT 2 The Nursing Role in Preparing Families for Childbearing and Childrearing Mesonephros Mesonephric duct Gonadal ridge Paramesonephric (Müllerian) duct Metanephros (kidney) Cloaca Ovaries Testes 5-6 week embryo sexually indifferent stage Efferent ductules Paramesonephric duct forming the Epididymis uterine tube Paramesonephric Mesonephric duct (degenerating) duct (degenerating) Mesonephric duct forming the Fused paramesonephric ductus deferens ducts forming the uterus Urinary bladder Urinary bladder Seminal vesicle (moved aside) Urogenital sinus forming the urethra Urogenital sinus forming the urethra and lower vagina 7-8 week male embryo 8-9 week female fetus Urinary bladder Uterine tube Seminal vesicle Ovary Prostate gland Bulbourethral Uterus gland Ductus deferens Urinary bladder (moved aside) Urethra Vagina Efferent ductules Urethra Epididymis Hymen Testis Vestibule Penis At birth At birth Male development Female development FIGURE 5.1 Development of the internal and external reproductive organs. CHAPTER 5 The Nursing Role in Reproductive and Sexual Health 89 Urethral fold Genital tubercle Labioscrotal swelling Anus Urethral groove Tail (cut) (a) Indifferent (approximately 5 weeks) Penis Clitoris Urogenital sinus Labioscrotal Labioscrotal swellings Urethral folds Urethral folds swellings (labia majora) (scrotum) (labia minora) Anus Anus At 10 weeks Glans penis Clitoris Labia minora Labia majora Scrotum Anus Anus Near term (b) Male development (c) Female development FIGURE 5.1 (continued) Vas deferens Rectum Urinary bladder Symphysis pubis Seminal vesicle Ejaculatory Penis: duct Corpus cavernosum Corpus spongiosum Prostate Urethra gland Anus Glans Bulbourethral Prepuce gland Bulb of penis Epididymis Testis Scrotum FIGURE 5.2 Male internal and external reproductive organs. 90 UNIT 2 The Nursing Role in Preparing Families for Childbearing and Childrearing each other more readily on sitting or muscular activity, and conducting sperm from the tubule to the vas deferens, the there is less possibility of trauma to them. Most body struc- next step in the passage to the outside. Because each epi- tures of importance are more protected than are the testes didymis is so tightly coiled, its length is extremely deceptive: (for example, the heart, kidneys, and lungs are surrounded by it is actually over 20 ft long. Some sperm are stored in the ribs of hard bone). Spermatozoa do not survive at a temper- epididymis, and a portion of the alkaline fluid that will sur- ature as high as that of the body, however, so the location of round sperm at maturity (semen, or seminal fluid that con- the testes outside the body, where the temperature is approx- tains a basic sugar and mucin, a form of protein) is produced imately 1° F lower than body temperature, provides protec- by the cells lining the epididymis. Because the epididymis is tion for sperm survival (McCance & Huether, 2007). so narrow along its entire length, infection of the epididymis Beginning in early adolescence, boys need to learn testic- can easily lead to scarring of the lumen that then prohibits ular self-examination so that they can detect tenderness or passage of sperm beyond the scarred point. any abnormal growth in the testes (see Chapter 34). Normal Sperm are immobile and incapable of fertilization as they testes feel firm, smooth, and egg shaped. The epididymis pass or are stored at the epididymis level. It takes at least 12 (the tube that carries sperm away from the testes) can be pal- to 20 days for them to travel the length of the epididymis pated as a firm swelling on the superior aspect of the testes. and a total of 64 days for them to reach maturity. This is one Caution boys not to mistake this structure for an abnormal reason that aspermia (absence of sperm) and oligospermia growth. (!20 million sperm/mL) are problems that do not appear to respond immediately to therapy but rather only after Penis. The penis is composed of three cylindrical masses of 2 months. erectile tissue in the penis shaft: two termed the corpus cav- ernosa, and a third termed the corpus spongiosum. The ure- Vas Deferens (Ductus Deferens). The vas deferens is an ad- thra passes through these layers of erectile tissue, making the ditional hollow tube surrounded by arteries and veins and penis serve as the outlet for both the urinary and the repro- protected by a thick fibrous coating. It carries sperm from ductive tracts in men. With sexual excitement, nitric oxide is the epididymis through the inguinal canal into the abdom- released from the endothelium of blood vessels. This results inal cavity, where it ends at the seminal vesicles and the ejac- in dilation of blood vessels and an increase in blood flow to ulatory ducts. Sperm mature as they pass through the vas the arteries of the penis (engorgement). The ischiocavernosus deferens. They are still not mobile at this point, however, muscle at the base of the penis then contracts, trapping both probably because of the fairly acidic medium of the semen venous and arterial blood in the three sections of erectile tis- produced at this level. The blood vessels and vas deferens sue and leading to distention and erection of the penis. The together are referred to as the spermatic cord. A varicocele, penile artery, a branch of the pudendal artery, provides the or a varicosity of the internal spermatic vein, was once blood supply for the penis. Penile erection is stimulated by thought to contribute to male subfertility by causing con- parasympathetic nerve innervation. gestion with increased warmth in the testes but this appears At the distal end of the organ is a bulging, sensitive ridge to actually make little difference (Evers & Collins, 2009). of tissue, the glans. A retractable casing of skin, the prepuce, Vasectomy (severing of the vas deferens to prevent passage protects the nerve-sensitive glans at birth. Many infants in of sperm) is a popular means of male birth control (Cook et the United States have the prepuce tissue removed surgically al., 2009). (circumcision) shortly after birth (Fig. 5.3). Seminal Vesicles. The seminal vesicles are two convoluted Male Internal Structures pouches that lie along the lower portion of the posterior sur- face of the bladder and empty into the urethra by way of the The male internal reproductive organs are the epididymis, ejaculatory ducts. These glands secrete a viscous alkaline liq- the vas deferens, the seminal vesicles, the ejaculatory ducts, uid that has a high sugar, protein, and prostaglandin con- the prostate gland, the urethra, and the bulbourethral glands tent. Sperm become increasingly motile with this added (see Fig. 5.2). fluid, because it surrounds them with nutrients and a more Epididymis. The seminiferous tubule of each testis leads to a favorable pH. tightly coiled tube, the epididymis, which is responsible for Ejaculatory Ducts. The two ejaculatory ducts pass through the prostate gland and join the seminal vesicles to the urethra. Prostate Gland. The prostate is a chestnut-sized gland that lies just below the bladder. The urethra passes through the center of it, like the hole in a doughnut. The prostate gland secretes a thin, alkaline fluid. When added to the secretion from the seminal vesicles and the accompanying sperm from the epididymis, this alkaline fluid further protects sperm from being immobilized by the naturally low pH level of the urethra. In middle life, many men develop benign hypertro- phy of the prostate. This swelling interferes with both fertil- ity and urination. A benign condition, it can be relieved by medical therapy or surgery but needs to be differentiated FIGURE 5.3 Uncircumcised and circumcised penis. from prostate cancer (Parsons, 2007). CHAPTER 5 The Nursing Role in Reproductive and Sexual Health 91 Bulbourethral Glands. Two bulbourethral or Cowper’s Mons Veneris. The mons veneris is a pad of adipose tissue glands lie beside the prostate gland and empty via short ducts located over the symphysis pubis, the pubic bone joint. It is into the urethra. Like the prostate gland and seminal vesicles, covered by a triangle of coarse, curly hairs. The purpose of they secrete an alkaline fluid that helps counteract the acid the mons veneris is to protect the junction of the pubic bone secretion of the urethra and ensure the safe passage of sper- from trauma. matozoa. Semen, therefore, is derived from the prostate gland (60%), the seminal vesicles (30%), the epididymis Labia Minora. Just posterior to the mons veneris spread two (5%), and the bulbourethral glands (5%). hairless folds of connective tissue, the labia minora. Before menarche, these folds are fairly small; by childbearing age, they Urethra. The urethra is a hollow tube leading from the base are firm and full; after menopause, they atrophy and again be- of the bladder, which, after passing through the prostate come much smaller. Normally the folds of the labia minora are gland, continues to the outside through the shaft and glans pink; the internal surface is covered with mucous membrane, of the penis. It is approximately 8 in (18 to 20 cm) long. and the external surface with skin. The area is abundant with Like other urinary tract structures, it is lined with mucous sebaceous glands, so localized sebaceous cysts may occur here. membrane. Women who perform monthly vulvar examinations are able to detect infection or other abnormalities of the vulva such as se- ✔Checkpoint Question 5.2 baceous cysts. Suppose Kevin Matthews tells you that he is considering a va- Labia Majora. The labia majora are two folds of adipose tis- sectomy after the birth of his new child. Vasectomy is incision sue covered by loose connective tissue and epithelium that of which organ? are positioned lateral to the labia minora. Covered by pubic a. The testes hair, the labia majora serve as protection for the external b. The vas deferens genitalia and the distal urethra and vagina. They are fused c. The epididymis anteriorly but separated posteriorly. Trauma to the area, d. The scrotum such as occurs from childbirth or rape, can lead to extensive edema formation because of the looseness of the connective Female Reproductive System tissue base. The female reproductive system, like the male system, has Other External Organs. The vestibule is the flattened, both external and internal components (Anderson & smooth surface inside the labia. The openings to the bladder Genadry, 2007). (the urethra) and the uterus (the vagina) both arise from the vestibule. The clitoris is a small (approximately 1 to 2 cm), Female External Structures rounded organ of erectile tissue at the forward junction of the labia minora. It is covered by a fold of skin, the prepuce. The structures that form the female external genitalia are The clitoris is sensitive to touch and temperature and is the termed the vulva (from the Latin word for “covering”) and center of sexual arousal and orgasm in a woman. Arterial are illustrated in Figure 5.4. blood supply for the clitoris is plentiful. When the ischio- Mons veneris Skene’s gland Clitoris Orifice of urethra Vaginal vestibule Labia minora Labia majora Hymen Orifice of vagina Perineum Bartholin’s gland Anus Fourchette FIGURE 5.4 Female external genitalia. 92 UNIT 2 The Nursing Role in Preparing Families for Childbearing and Childrearing cavernosus muscle surrounding it contracts with sexual Vulvar Blood Supply. The blood supply of the external arousal, the venous outflow for the clitoris is blocked, lead- genitalia is mainly from the pudendal artery and a portion ing to clitoral erection. of the inferior rectus artery. Venous return is through the Two Skene’s glands (paraurethral glands) are located just pudendal vein. Pressure on this vein by the fetal head can lateral to the urinary meatus, one on each side. Their ducts cause extensive back-pressure and development of varicosi- open into the urethra. Bartholin’s glands (vulvovaginal ties (distended veins) in the labia majora. Because of the glands) are located just lateral to the vaginal opening on both rich blood supply, trauma to the area, such as occurs from sides. Their ducts open into the distal vagina. Secretions pressure during childbirth, can cause large hematomas. from both of these glands help to lubricate the external gen- This ready blood supply also contributes to the rapid heal- italia during coitus. The alkaline pH of their secretions helps ing of any tears in the area after childbirth (McCance & to improve sperm survival in the vagina. Both Skene’s glands Huether, 2007). and Bartholin’s glands may become infected and produce a discharge and local pain. Vulvar Nerve Supply. The anterior portion of the vulva de- The fourchette is the ridge of tissue formed by the poste- rives its nerve supply from the ilioinguinal and gen- rior joining of the two labia minora and the labia majora. itofemoral nerves (L1 level). The posterior portions of the This is the structure that is sometimes cut (episiotomy) dur- vulva and vagina are supplied by the pudendal nerve (S3 ing childbirth to enlarge the vaginal opening. level). Such a rich nerve supply makes the area extremely Posterior to the fourchette is the perineal muscle or the sensitive to touch, pressure, pain, and temperature. Normal perineal body. Because this is a muscular area, it is easily stretching of the perineum with childbirth causes tempo- stretched during childbirth to allow for enlargement of the rary loss of sensation in the area. Anesthesia for childbirth vagina and passage of the fetal head. Many exercises suggested may be administered locally to block the pudendal nerve, for pregnancy (such as Kegel’s, squatting, and tailor-sitting) further eliminating pain sensation at the perineum during are aimed at making the perineal muscle more flexible to birth. allow easier expansion during birth without tearing of this tissue. Female Internal Structures The hymen is a tough but elastic semicircle of tissue that Female internal reproductive organs (Fig. 5.5) are the covers the opening to the vagina in childhood. It is often torn ovaries, the fallopian tubes, the uterus, and the vagina. during the time of first sexual intercourse. However, because of the use of tampons and active sports participation, many girls Ovaries. The ovaries are approximately 4 cm long by 2 cm who have not had sexual relations do not have intact hymens in diameter and approximately 1.5 cm thick, or the size and at the time of their first pelvic examination. Occasionally, a shape of almonds. They are grayish white and appear girl has an imperforate hymen, or a hymen so complete that it pitted, or with minute indentations on the surface. An does not allow for passage of menstrual blood from the vagina unruptured, glistening, clear, fluid-filled graafian follicle or for sexual relations until it is surgically incised (Dane (an ovum about to be discharged) or a miniature yellow et al., 2007). corpus luteum (the structure left behind after the ovum has Ovary Sacrum Fallopian tube Round ligament Sacrococcygeal joint Fundus of uterus Coccyx Body of uterus Urinary Rectum bladder Symphysis pubis Cervix Urethra Vagina Clitoris Anus Labia minora Labia majora FIGURE 5.5 Female internal reproductive organs. CHAPTER 5 The Nursing Role in Reproductive and Sexual Health 93 been discharged) often can be observed on the surface of The oocytes, like sperm, differ from all other body cells in an ovary. the number of chromosomes they contain in the nucleus. The Ovaries are located close to and on both sides of the uterus nucleus of all other human body cells contains 46 chromo- in the lower abdomen. It is difficult to locate them by ab- somes, consisting of 22 pairs of autosomes (paired matching dominal palpation because they are situated so low in the chromosomes) and 1 pair of sex chromosomes (two X sex abdomen. If an abnormality is present, such as an enlarging chromosomes in the female, an X and a Y sex chromosome ovarian cyst, the resulting tenderness may be evident on pair in the male). Reproductive cells (both ova and spermato- lower-left or lower-right abdominal palpation. zoa) have only half the usual number of chromosomes, so that, The function of the two ovaries (the female gonads) is to when they combine (fertilization), the new individual formed produce, mature, and discharge ova (the egg cells). In the from them will have the normal number of 46 chromosomes. process, the ovaries produce estrogen and progesterone and If both the ova and the spermatozoa carried the full comple- initiate and regulate menstrual cycles. If the ovaries are re- ment of chromosomes, a new individual formed from them moved before puberty (or are nonfunctional), the resulting ab- would have twice the normal number. There is a difference in sence of estrogen prevents breasts from maturing at puberty; the way reproductive cells divide that causes this change in in addition, pubic hair distribution assumes a more male pat- chromosome number. tern than normal. After menopause, or cessation of ovarian Cells in the body, such as skin cells, undergo cell divi- function, the uterus, breasts, and ovaries all undergo atrophy sion by mitosis, or daughter cell division. In this type of di- or a reduction in size because of a lack of estrogen. Ovarian vision, all the chromosomes are duplicated in each cell just function, therefore, is necessary for maturation and mainte- before cell division, giving every new cell the same number nance of secondary sex characteristics in females. The estrogen of chromosomes as the original parent cell. Oocytes divide secreted by ovaries is also important to prevent osteoporosis, in intrauterine life by one mitotic division. Division activ- or weakness of bones, because of withdrawal of calcium from ity then appears to halt until at least puberty, when a sec- bones. This frequently occurs in women after menopause, ond type of cell division, meiosis (cell reduction division), making women prone to serious spinal, hip, and wrist frac- occurs. In the male, this reduction division occurs just be- tures. Because cholesterol is incorporated into estrogen, the fore the spermatozoa mature. In the female, it occurs just production of estrogen is thought to also keep cholesterol lev- before ovulation. After this reduction division, an ovum has els reduced, thus limiting the effects of atherosclerosis (artery 22 autosomes and an X sex chromosome, whereas a sper- disease) in women. Estrogen used to be prescribed for women matozoon has 22 autosomes and either an X or a Y sex at menopause to help prevent osteoporosis and cardiovascular chromosome. A new individual formed from the union of disease. However, this type of long-term estrogen supplemen- an ovum and an X-carrying spermatozoon will be female tation may contribute to breast cancer and cerebrovascular ac- (an XX chromosome pattern); an individual formed from cidents, so it is no longer routinely recommended (Kulp & the union of an ovum and a Y-carrying spermatozoon will Zacur, 2007). be male (an XY chromosome pattern). The ovaries are held suspended and in close contact with the ends of the fallopian tubes by three strong supporting ligaments Maturation of Oocytes. Each oocyte lies in the ovary sur- attached to the uterus or the pelvic wall. They are unique rounded by a protective sac, or thin layer of cells, called a among pelvic structures in that they are not covered by a layer primordial follicle. Between 5 and 7 million ova form in of peritoneum. Because they are not encased in this way, ova utero. The majority never develop beyond the primitive can escape from them and enter the uterus by way of the fal- state and actually atrophy, so that by birth only 2 million lopian tubes. Because they are suspended in position rather than are present. By age 7 years, only approximately 500,000 are being firmly fixed in place, an abnormal tumor or cyst growing present in each ovary; by 22 years, there are approximately on them can enlarge to a size easily twice that of the organ be- 300,000; and by menopause, none are left (all have either fore pressure on surrounding organs or the ovarian blood sup- matured or atrophied). “The point at which no function- ply leads to symptoms of compression. This is the reason that ing oocytes remain in the ovaries” is one definition of ovarian cancer continues to be one of the leading causes of menopause. death from cancer in women (i.e., the tumor grows without symptoms for an extended period) (Neves-E-Castro, 2007). Fallopian Tubes. The fallopian tubes arise from each upper Ovaries have three principal divisions: corner of the uterine body and extend outward and backward 1. Protective layer of surface epithelium until each opens at its distal end, next to an ovary. Fallopian 2. Cortex, where the immature (primordial) oocytes mature tubes are approximately 10 cm long in a mature woman. into ova and large amounts of estrogen and progesterone Their function is to convey the ovum from the ovaries to the are produced uterus and to provide a place for fertilization of the ovum by 3. Central medulla, which contains the nerves, blood ves- sperm. sels, lymphatic tissue, and some smooth muscle tissue Although a fallopian tube is a smooth, hollow tunnel, it is anatomically divided into four separate parts (Fig. 5.6). The Division of Reproductive Cells (Gametes). At birth, each most proximal division, the interstitial portion, is that part of ovary contains approximately 2 million immature ova the tube that lies within the uterine wall. This portion is only (oocytes), which were formed during the first 5 months of in- about 1 cm in length; the lumen of the tube is only 1 mm in trauterine life. Although these cells have the unique ability to diameter at this point. The isthmus is the next distal portion. produce a new individual, they basically contain the usual It is approximately 2 cm in length and like the interstitial components of cells: a cell membrane, an area of clear cyto- tube, is extremely narrow. This is the portion of the tube that plasm, and a nucleus containing chromosomes. is cut or sealed in a tubal ligation, or tubal sterilization 94 UNIT 2 The Nursing Role in Preparing Families for Childbearing and Childrearing Fallopian tube: Ovary Fimbria Infundibulum Ampulla Fundus of uterus Isthmus Ovarian ligament Interstitial Broad Uterus: Round ligament Corpus Cervix: ligament Isthmus Internal os Vagina Cervical canal External os FIGURE 5.6 Anterior view of female reproductive organs showing relationship of fallopian tubes and body of the uterus. procedure. The ampulla is the third and also the longest por- organ; the uterine body is the smallest). When a girl reaches tion of the tube. It is approximately 5 cm in length. It is in approximately 8 years of age, an increase in the size of the this portion that fertilization of an ovum usually occurs. The uterus begins. An adolescent is closer to 17 years old before infundibular portion is the most distal segment of the tube. the uterus reaches its adult size. This may be a contributing It is approximately 2 cm long and is funnel shaped. The rim factor to the low-birth-weight babies typically born to ado- of the funnel is covered by fimbria (small hairs) that help to lescents younger than this age. guide the ovum into the fallopian tube. With maturity, a uterus is approximately 5 to 7 cm long, The lining of the entire fallopian tube is composed of mu- 5 cm wide, and, in its widest upper part, 2.5 cm deep. In a cous membrane, which contains both mucus-secreting and nonpregnant state, it weighs approximately 60 g. The func- ciliated (hair-covered) cells. Beneath the mucous lining is tion of the uterus is to receive the ovum from the fallopian connective tissue and a circular muscle layer. The muscle tube; provide a place for implantation and nourishment; fur- layer of the tube produces peristaltic motions that help con- nish protection to a growing fetus; and, at maturity of the duct the ovum the length of the tube. Migration of the ovum fetus, expel it from a woman’s body. is also aided by the action of the ciliated lining and the After a pregnancy, the uterus never returns to its non- mucus, which acts as a lubricant. The mucus produced may pregnant size but remains approximately 9 cm long, 6 cm also act as a source of nourishment for the fertilized egg, be- wide, 3 cm thick, and 80 g in weight. cause it contains protein, water, and salts. Anatomically, the uterus consists of three divisions: the Because the fallopian tubes are open at their distal ends, a body or corpus, the isthmus, and the cervix. The body of the direct pathway exists from the external organs, through the uterus is the uppermost part and forms the bulk of the organ. vagina to the uterus and tubes, to the peritoneum. This path- The lining of the cavity is continuous with that of the fal- way makes conception possible. It can also lead to infection lopian tubes, which enter at its upper aspects (the cornua). of the peritoneum (peritonitis) if disease spreads from the During pregnancy, the body of the uterus is the portion of perineum through the tubes to the pelvic cavity. For this rea- the structure that expands to contain the growing fetus. The son, careful, clean technique must be used during pelvic ex- portion of the uterus between the points of attachment of the aminations or treatment. Vaginal examinations during labor fallopian tubes is termed the fundus. The fundus is also the and birth are done with sterile technique to ensure that no portion that can be palpated abdominally to determine the organisms can enter. amount of uterine growth occurring during pregnancy, to measure the force of uterine contractions during labor, and Uterus. The uterus is a hollow, muscular, pear-shaped organ to assess that the uterus is returning to its nonpregnant state located in the lower pelvis, posterior to the bladder and an- after childbirth. terior to the rectum. During childhood, it is approximately The isthmus of the uterus is a short segment between the the size of an olive, and its proportions are reversed from body and the cervix. In the nonpregnant uterus, it is only what they are later (i.e., the cervix is the largest portion of the 1 to 2 mm in length. During pregnancy, this portion also CHAPTER 5 The Nursing Role in Reproductive and Sexual Health 95 enlarges greatly to aid in accommodating the growing fetus. layers, thereby limiting the loss of blood in the woman. It is the portion of the uterus that is most commonly cut Myomas, or benign fibroid (leiomyoma) tumors, arise from when a fetus is born by a cesarean birth. the myometrium (McCance & Heuther, 2007). The cervix is the lowest portion of the uterus. It represents The perimetrium, or the outermost layer of the uterus, serves approximately one third of the total uterus size and is ap- the purpose of adding strength and support to the structure. proximately 2 to 5 cm long. Approximately half of it lies Uterine Blood Supply. The large descending abdominal above the vagina and half extends into the vagina. Its central aorta divides to form two iliac arteries; main divisions of the cavity is termed the cervical canal. The opening of the canal iliac arteries are the hypogastric arteries (Fig. 5.7). These fur- at the junction of the cervix and isthmus is the internal cer- ther divide to form the uterine arteries and supply the uterus. vical os; the distal opening to the vagina is the external cervi- Because the uterine blood supply is not far removed from the cal os. The level of the external os is at the level of the ischial aorta, it is copious and adequate to supply the growing needs spines (an important relationship in estimating the level of of a fetus. As an additional safeguard, after supplying the ovary the fetus in the birth canal). with blood, the ovarian artery (a direct subdivision of the Uterine and Cervical Coats. The uterine wall consists of aorta) joins the uterine artery as a fail-safe system to ensure that three separate coats or layers of tissue: an inner one of mu- the uterus will have an adequate blood supply. The blood ves- cous membrane (the endometrium), a middle one of muscle sels that supply the cells and lining of the uterus are tortuous fibers (the myometrium), and an outer one of connective tis- against the sides of the uterine body in nonpregnant women. sue (the perimetrium). As a uterus enlarges with pregnancy, the vessels “unwind” and The endometrium layer of the uterus is the one that is im- so can stretch to maintain an adequate blood supply as the portant for menstrual function. It is formed by two layers of organ enlarges. The uterine veins follow the same twisting cells. The layer closest to the uterine wall, the basal layer, re- course as the arteries; they empty into the internal iliac veins. mains stable, uninfluenced by hormones. In contrast, the inner glandular layer is greatly influenced by both estrogen and prog- esterone. It grows and becomes so thick and responsive each month under the influence of estrogen and progesterone that it is capable of supporting a pregnancy. If pregnancy does not occur, this is the layer that is shed as the menstrual flow. The mucous membrane lining the cervix is termed the en- docervix. The endocervix, continuous with the endometrium, is also affected by hormones, but changes are manifested in a more subtle way. The cells of the cervical lining secrete mucus to provide a lubricated surface so that spermatozoa can readily pass through the cervix; the efficiency of this lubrication increases or wanes depending on hormone stimulation. At the point in the menstrual cycle when estrogen production is at its peak, as much as 700 mL of mucus per day is produced; Aorta at the point that estrogen is very low, only a few milliliters Kidney Inferior are produced. Because mucus is alkaline, it helps to decrease vena cava the acidity of the upper vagina, aiding in sperm survival. Ureter Ovarian During pregnancy, the endocervix becomes plugged with artery and vein mucus, forming a seal to keep out ascending infections (the operculum). The lower surface of the cervix and the lower third of the cervical canal are lined not with mucous membrane but with Hypogastric stratified squamous epithelium, similar to that lining the artery vagina. Locating the point at which this tissue changes from epithelium to mucous membrane is important when obtain- ing a Papanicolaou smear (a test for cervical cancer), because this tissue interface is most often the origin of cervical cancer. The myometrium, or muscle layer of the uterus, is com- posed of three interwoven layers of smooth muscle, the fibers of which are arranged in longitudinal, transverse, and oblique Ovary directions. This network offers extreme strength to the organ. The myometrium serves the important function of Uterine constricting the tubal junctions and preventing regurgitation artery and vein of menstrual blood into the tubes. It also holds the internal cervical os closed during pregnancy to prevent a preterm Uterus birth. When the uterus contracts at the end of pregnancy to expel the fetus, equal pressure is exerted at all points through- Bladder out the cavity because of its unique arrangement of muscle fibers. After childbirth, this interlacing network of fibers is able to constrict the blood vessels coursing through the FIGURE 5.7 Blood supply to the uterus. 96 UNIT 2 The Nursing Role in Preparing Families for Childbearing and Childrearing An important organ relationship to be aware of is the asso- The broad ligaments are two folds of peritoneum that cover ciation of uterine vessels and the ureters. The ureters from the the uterus front and back and extend to the pelvic sides to help kidneys pass directly in back of the ovarian vessels, near the fal- steady the uterus. The round ligaments are two fibrous, mus- lopian tubes. As shown in Figure 5.7, they cross just beneath cular cords that pass from the body of the uterus near the at- the uterine vessels before they enter the bladder. This close tachments of the fallopian tubes, through the broad ligaments anatomic relationship has implications in procedures such as and into the inguinal canal, inserting into the fascia of the tubal ligation, cesarean birth, and hysterectomy (removal of the vulva. The round ligaments act as additional “stays” to further uterus), because a ureter may be injured by a clamp if bleeding steady the uterus. If a pregnant woman moves quickly, she is controlled by clamping of the uterine or ovarian vessels. may pull one of these ligaments. This causes a quick, sharp Uterine Nerve Supply. The uterus is supplied by both ef- pain of frightening intensity in one of her lower abdominal ferent (motor) and afferent (sensory) nerves. The efferent quadrants that can be mistaken for labor pain. nerves arise from the T5 through T10 spinal ganglia. The af- ferent nerves join the hypogastric plexus and enter the spinal What if... Suzanne Matthews decides to have a tubal column at T11 and T12. The fact that sensory innervation ligation (clamping of the fallopian tubes) after the birth from the uterus registers lower in the spinal column than of her baby? Why is observing women for urine output does motor control has implications in controlling pain in after uterine or fallopian tube surgery of this kind al- labor. An anesthetic solution can be injected near the spinal ways a critical assessment? column to stop the pain of uterine contractions at the T11 and T12 levels without stopping motor control or contrac- Uterine Deviations. Several uterine deviations (shape and tions (registered higher, at the T5 to T10 level). This is the position) may interfere with fertility or pregnancy. In the principle of epidural and spinal anesthesia (see Chapter 16). fetus, the uterus first forms with a septum or a fibrous divi- Uterine Supports. The uterus is suspended in the pelvic sion, longitudinally separating it into two portions. As the cavity by several ligaments that also help support the bladder fetus matures, this septum dissolves, so that typically at birth and is further supported by a combination of fascia and mus- no remnant of the division remains. In some women, the cle. Because it is not fixed, the uterus is free to enlarge without septum never atrophies, and so the uterus remains as two sep- discomfort during pregnancy. If its ligaments become over- arate compartments. In others, half of the septum is still pres- stretched during pregnancy, they may not support the bladder ent. Still other women have oddly shaped “horns” at the well afterward, and the bladder can then herniate into the an- junction of the fallopian tubes, termed a bicornuate uterus. terior vagina (a cystocele). If the rectum pouches into the vagi- Any of these malformations may decrease the ability to con- nal wall, a rectocele (Fig. 5.8) develops (American College of ceive or to carry a pregnancy to term (Krantz, 2007). Some Obstetricians and Gynecologists [ACOG], 2007). variations of uterine formation are shown in Figure 5.9. The A fold of peritoneum behind the uterus forms the posterior specific effects of these deviations on fertility and pregnancy ligament. This creates a pouch (Douglas’ cul-de-sac) between are discussed in later chapters. the rectum and uterus. Because this is the lowest point of the Ordinarily, the body of the uterus is tipped slightly for- pelvis, any fluid such as blood that accumulates from a condi- ward. Positional deviations of the uterus commonly seen are: tion such as a ruptured tubal (ectopic) pregnancy tends to col- lect in this space. The space can be examined for the presence Anteversion, a condition in which the entire uterus is of fluid or blood to help in diagnosis by inserting a culdoscope tipped far forward through the posterior vaginal wall (culdoscopy) or a laparo- Retroversion, a condition in which the entire uterus is scope through the abdominal wall (laparoscopy). tipped backward Cul-de-sac of Douglas Rectum Vagina Vagina Urinary bladder Rectocele Cystocele A B FIGURE 5.8 (A) Cystocele. The bladder has herniated into the anterior wall of the vagina. (B) Rectocele. The rectum has herniated into the posterior vaginal wall. CHAPTER 5 The Nursing Role in Reproductive and Sexual Health 97 A B C D FIGURE 5.9 (A) Normal uterus. (B) Bicornuate uterus. (C) Septum dividing uterus. (D) Double uterus. Abnormal shapes of uterus allow less placenta implantation space. Anteflexion, a condition in which the body of the uterus may interfere with fertility, because they can block the depo- is bent sharply forward at the junction with the cervix sition or migration of sperm. Examples of these abnormal Retroflexion, a condition in which the body is bent uterine positions are shown in Figure 5.10. sharply back just above the cervix Minor variations of these positions do not cause reproduc- Vagina. The vagina is a hollow, musculomembranous canal tive problems. Extreme abnormal flexion or version positions located posterior to the bladder and anterior to the rectum. Normal position B A C D FIGURE 5.10 Uterine flexion and version. (A) Anteversion. (B) Anteflexion. (C) Retroversion. (D) Retroflexion. 98 UNIT 2 The Nursing Role in Preparing Families for Childbearing and Childrearing It extends from the cervix of the uterus to the external vulva. excitement, often attributed to vaginal stimulation, is influ- Its function is to act as the organ of intercourse and to con- enced mainly by clitoral stimulation. vey sperm to the cervix so that sperm can meet with the The mucus produced by the vaginal lining has a rich glyco- ovum in the fallopian tube. With childbirth, it expands to gen content. When this glycogen is broken down by the lac- serve as the birth canal. tose-fermenting bacteria that frequent the vagina (Döderlein’s When a woman is lying on her back, as she does for a bacillus), lactic acid is formed. This makes the usual pH of the pelvic examination, the course of the vagina is inward and vagina acid, a condition detrimental to the growth of patho- downward. Because of this downward slant and the angle of logic bacteria, so that even though the vagina connects directly the uterine cervix, the length of the anterior wall of the to the external surface, infection does not readily occur. vagina is approximately 6 to 7 cm; the posterior wall is 8 to Instruct women not to use vaginal douches or sprays as a daily 9 cm. At the cervical end of the structure, there are recesses hygiene measure because they may clean away this natural acid on all sides of the cervix, termed fornices. Behind the cervix medium of the vagina, inviting vaginal infections. After is the posterior fornix; at the front, the anterior fornix; and at menopause, the pH of the vagina becomes closer to 7.5 or the sides, the lateral fornices. The posterior fornix serves as a slightly alkaline, a reason that vulvovaginitis infections occur place for the pooling of semen after coitus; this allows a large more frequently in women in this age group (Selby, 2007). number of sperm to remain close to the cervix and encour- ages sperm migration into the cervix. ✔Checkpoint Question 5.3 The vaginal wall is so thin at the fornices that the bladder On physical examination, Suzanne Matthews is found to have can be palpated through the anterior fornix, the ovaries a cystocele. A cystocele is: through the lateral fornices, and the rectum through the pos- terior fornix. The vagina is lined with stratified squamous ep- a. A sebaceous cyst arising from a vulvar fold. ithelium similar to that covering the cervix. It has a middle b. Protrusion of the intestine into the vagina. connective tissue layer and a strong muscular wall. Normally, c. Prolapse of the uterus and cervix into the vagina. the walls contain many folds or rugae that lie in close ap- d. Herniation of the bladder into the vaginal wall. proximation to each other. These folds make the vagina very elastic and able to expand at the end of pregnancy to allow a Breasts full-term baby to pass through without tearing. A circular The mammary glands, or breasts, form from ectodermic tis- muscle, the bulbocavernosus, at the external opening of the sue early in utero. They then remain in a halted stage of de- vagina acts as a voluntary sphincter. Relaxing and tensing this velopment until a rise in estrogen at puberty produces a external vaginal sphincter muscle a set number of times each marked increase in their size. The size increase occurs mainly day makes it more supple for birth and helps maintain tone because of an increase of connective tissue plus deposition of after birth (Kegel’s exercises). fat. The glandular tissue of the breasts, necessary for success- The blood supply to the vagina is furnished by the vaginal ful breastfeeding, remains undeveloped until a first preg- artery, a branch of the internal iliac artery. Vaginal tears at nancy begins. Boys may notice a temporary increase in breast childbirth tend to bleed profusely because of this rich blood size at puberty, termed gynecomastia. If boys are not pre- supply. The same rich blood supply is also the reason that pared that this is a normal change of puberty, they may be any vaginal trauma at birth heals rapidly. concerned that they are developing abnormally. The change The vagina has both sympathetic and parasympathetic is most evident in obese boys (Ma & Geffner, 2008). nerve innervations originating at the S1 to S3 levels. The Breasts are located anterior to the pectoral muscle (Fig. vagina is not an extremely sensitive organ, however. Sexual 5.11), and in many women breast tissue extends well into the Ribs and cartilage Pectoral muscle Lobule Duct Ampulla A B C FIGURE 5.11 Anatomy of the breast. (A) Nonpregnant. (B) Pregnant. (C) During lactation. CHAPTER 5 The Nursing Role in Reproductive and Sexual Health 99 TABLE 5.1 ✽ Characteristics of Normal Menstrual Cycles Characteristic Description Beginning (menarche) Average age at onset, 12.4 years; average range, 9–17 years Interval between cycles Average, 28 days; cycles of 23–35 days not unusual Duration of menstrual flow Average flow, 2–7 days; ranges of 1–9 days not abnormal Amount of menstrual flow Difficult to estimate; average 30–80 mL per menstrual period; saturating pad or tampon in less than an hour is heavy bleeding Color of menstrual flow Dark red; a combination of blood, mucus, and endometrial cells Odor Similar to that of marigolds axilla. Breast self-examinations are not as effective in detecting of one menstrual flow to the beginning of the next). It is not early breast lesions as once believed and so are no longer rou- unusual for cycles to be as short as 23 days or as long as 35 tinely recommended (Kosters & Gotzsche, 2007). Women days. The length of the average menstrual flow (termed should have a yearly breast examination done by a health care menses) is 4 to 6 days, although women may have periods as professional, however, as this can detect breast disease. When short as 2 days or as long as 7 days (MacKay, 2009). palpating for breast health this way, always include the axillary Because there is such variation in length, frequency, and region in the examination, or some breast tissue can be missed. amount of menstrual flow and such variation in the onset of Milk glands of the breasts are divided by connective tissue menarche, many women have questions about what is con- partitions into approximately 20 lobes. All of the glands in sidered normal. Contact with health care personnel during a each lobe produce milk by acinar cells and deliver it to the yearly health examination or prenatal visit may be their first nipple via a lactiferous duct. The nipple has approximately opportunity to ask questions they have had for some time. 20 small openings through which milk is secreted. An am- Table 5.1 summarizes the normal characteristics of menstru- pulla portion of the duct, located just posterior to the nipple, ation for quick reference. serves as a reservoir for milk before breastfeeding. A nipple is composed of smooth muscle that is capable of Physiology of Menstruation erection on manual or sucking stimulation. On stimulation, it transmits sensations to the posterior pituitary gland to re- Four body structures are involved in the physiology of the lease oxytocin. Oxytocin acts to constrict milk gland cells and menstrual cycle: the hypothalamus, the pituitary gland, the push milk forward into the ducts that lead to the nipple. The ovaries, and the uterus. For a menstrual cycle to be complete, skin surrounding the nipples is darkly pigmented out to ap- all four structures must contribute their part; inactivity of any proximately 4 cm and is termed the areola. The area appears part results in an incomplete or ineffective cycle (Fig. 5.12). rough on the surface because it contains many sebaceous glands, called Montgomery’s tubercles. The blood supply to the breasts is profuse because it is supplied by thoracic branches of the axillary, internal mam- Hypothalamus mary, and intercostal arteries. This effective blood supply is important in bringing nutrients to the milk glands and LHRH makes possible a plentiful supply of milk for breastfeeding. However, it also aids in the metastasis of breast cancer if this Pituitary is not discovered early with breast examination or mammog- s ne o raphy (McCance & Huether, 2007). m og sterone o p i c h or Estr en og e MENSTRUATION otr Pr ad A menstrual cycle (a female reproductive cycle) is episodic n uterine bleeding in response to cyclic hormonal changes. The Go purpose of a menstrual cycle is to bring an ovum to maturity Ovary and renew a uterine tissue bed that will be responsible for the ova’s growth should it be fertilized. It is the process that allows oges erone for conception and implantation of a new life. Because menar- Estr en che may occur as early as 9 years of age, it is good to include og t health teaching information on menstruation to both school age children and their parents as early as fourth grade as part Pr of routine care. It is a poor introduction to sexuality and wom- anhood for a girl to begin menstruation unwarned and unpre- Uterus pared for the important internal function it represents. The length of menstrual cycles differs from woman to FIGURE 5.12 The interaction of pituitary-uterine-ovarian woman, but the average length is 28 days (from the beginning functions in a menstrual cycle. 100 UNIT 2 The Nursing Role in Preparing Families for Childbearing and Childrearing Hypothalamus After an upsurge of LH from the pituitary, prostaglandins are released and the graafian follicle ruptures. The ovum is set The release of GnRH (also called luteinizing hormone– free from the surface of the ovary, a process termed ovula- releasing hormone, or LHRH) by the hypothalamus initiates tion. It is swept into the open end of a fallopian tube. Teach the menstrual cycle. When the level of estrogen (produced by women that ovulation occurs on approximately the 14th day the ovaries) rises, release of the hormone is repressed, and before the onset of the next cycle, not necessarily at a cycle’s menstrual cycles do not occur (the principle that birth control midpoint. Because periods are typically 28 days, making the pills use to eliminate menstrual flow). During childhood, the 14th day the middle of the cycle, many women believe in- hypothalamus is apparently so sensitive to the small amount correctly that the midpoint of their cycle is their day of ovu- of estrogen produced by the adrenal glands that release of the lation. If their cycle is only 20 days long, however, their day hormone is suppressed. Beginning with puberty, the hypo- of ovulation would be day 6 (14 days from the end of the thalamus becomes less sensitive to estrogen feedback; this re- cycle). If a cycle is 44 days long, ovulation would occur on sults in the initiation every month in females of the hormone day 30, not day 22. GnRH. GnRH is transmitted from the hypothalamus to the After the ovum and the follicular fluid have been dis- anterior pituitary gland and signals the gland to begin pro- charged from the ovary, the cells of the follicle remain in the ducing the gonadotropic hormones FSH and LH. Because form of a hollow, empty pit. The FSH has done its work at production of GnRH is cyclic, menstrual periods also cycle. this point and now decreases in amount. The second pitu- Diseases of the hypothalamus that cause deficiency of this itary hormone, LH, continues to rise in amount and acts on releasing factor can result in delayed puberty. Likewise, a dis- the follicle cells of the ovary. It influences the follicle cells to ease that causes early activation of GnRH can lead to abnor- produce lutein, a bright-yellow fluid. Lutein is high in prog- mally early sexual development or precocious puberty esterone and contains some estrogen, whereas the follicular (Kaplowitz, 2007) (see Chapter 47). In addition to the in- fluid was high in estrogen with some progesterone. This yel- hibitory feedback mechanism of estrogen and progesterone low fluid fills the empty follicle, which is then termed a cor- that halts production of the releasing factor for the remain- pus luteum (yellow body). der of each month, high levels of pituitary-based hormones The basal body temperature of a woman drops slightly (by such as prolactin, FSH, or LH can also inhibit the produc- 0.5° to 1° F) just before the day of ovulation, because of the tion of GnRH. extremely low level of progesterone that is present at that time. It rises by 1° F on the day after ovulation, because of Pituitary Gland the concentration of progesterone (which is thermogenic) Under the influence of GnRH, the anterior lobe of the pitu- that is present at that time. The woman’s temperature re- itary gland (the adenohypophysis) produces two hormones mains at this level until approximately day 24 of the men- that act on the ovaries to further influence the menstrual strual cycle, when the progesterone level again decreases cycle: (a) FSH, a hormone that is active early in the cycle and (McCance & Huether, 2007). is responsible for maturation of the ovum, and (b) LH, a hor- If conception (fertilization by a spermatozoon) occurs as mone that becomes most active at the midpoint of the cycle the ovum proceeds down a fallopian tube and the fertilized and is responsible for ovulation, or release of the mature egg ovum implants on the endometrium of the uterus, the cor- cell from the ovary, and growth of the uterine lining during pus luteum remains throughout the major portion of the the second half of the menstrual cycle. pregnancy (approximately 16 to 20 weeks). If conception does not occur, the unfertilized ovum atrophies after 4 or 5 Ovary days, and the corpus luteum (called a “false” corpus lu- teum) remains for only 8 to 10 days. As the corpus luteum FSH and LH are called gonadotropic hormones because they regresses, it is gradually replaced by white fibrous tissue, cause growth (trophy) in the gonads (ovaries). Every month and the resulting structure is termed a corpus albicans during the fertile period of a woman’s life (from menarche to (white body). Figure 5.13 shows the times when ovarian menopause), one of the ovary’s primordial follicles is activated hormones are secreted at peak levels during a typical 28-day by FSH to begin to grow and mature. As it grows, its cells pro- menstrual cycle. duce a clear fluid (follicular fluid) that contains a high degree of estrogen (mainly estradiol) and some progesterone. As the follicle reaches its maximum size, it is propelled toward the Uterus surface of the ovary. At full maturity, it is visible on the surface Figure 5.13 also illustrates uterine changes that occur of the ovary as a clear water blister approximately 0.25 to monthly as a result of stimulation from the hormones pro- 0.5 inches across. At this stage of maturation, the small ovum duced by the ovaries. (barely visible to the naked eye, approximately the size of a printed period), with its surrounding follicle membrane and First Phase of Menstrual Cycle (Proliferative). Immediately fluid, is termed a graafian follicle. after a menstrual flow (which occurs during the first 4 or 5 By day 14 before the end of a menstrual cycle (the mid- days of a cycle), the endometrium, or lining of the uterus, point of a typical 28-day cycle), the ovum has divided by mi- is very thin, approximately one cell layer in depth. As the totic division into two separate bodies: a primary oocyte, ovary begins to produce estrogen (in the follicular fluid, which contains the bulk of the cytoplasm, and a secondary under the direction of the pituitary FSH), the endo- oocyte, which contains so little cytoplasm that it is not func- metrium begins to proliferate. This growth is very rapid tional. The structure also has accomplished its meiotic divi- and increases the thickness of the endometrium approxi- sion, reducing its number of chromosomes to the haploid mately eightfold. This increase continues for the first half (having only one member of a pair) number of 23. of the menstrual cycle (from approximately day 5 to day CHAPTER 5 The Nursing Role in Reproductive and Sexual Health 101 100 500 20 18 80 400 16 14 60 FSH (mIU/mL) LH (mIU/mL) 300 12 Prog (ng/mL) E (pg/mL) 10 40 200 8 6 20 100 4 2 0 0 Days of cycle -14 -12 -10 -8 -6 -4 -2 0 2 4 6 8 10 12 14 Estrogen LH A Progesterone FSH Ovarian follicle Uterine thickness Days 1 5 10 15 20 25 28 5 Uterine Menstrual Proliferative Secretory phases flow phase phase FIGURE 5.13 (A) Plasma hormone concen- trations in the normal female reproductive Ovarian Follicular Ovulation Luteal cycle. (B) Ovarian events and uterine B phases changes during the menstrual cycle. 14). This half of a menstrual cycle is termed interchange- progesterone and estrogen decreases. With the withdrawal of ably the proliferative, estrogenic, follicular, or postmen- progesterone stimulation, the endometrium of the uterus be- strual phase. gins to degenerate (at approximately day 24 or day 25 of the cycle). The capillaries rupture, with minute hemorrhages, Second Phase of Menstrual Cycle (Secretory). After ovula- and the endometrium sloughs off. tion, the formation of progesterone in the corpus luteum (under the direction of LH) causes the glands of the uterine endometrium to become corkscrew or twisted in appearance Fourth Phase of a Menstrual Cycle (Menses). Menses, or and dilated with quantities of glycogen (an elementary sugar) the menstrual flow, is composed of: and mucin (a protein). The capillaries of the endometrium Blood from the ruptured capillaries increase in amount until the lining takes on the appearance Mucin from the glands of rich, spongy velvet. This second phase of the menstrual Fragments of endometrial tissue cycle is termed the progestational, luteal, premenstrual, or se- The microscopic, atrophied, and unfertilized ovum cretory phase. Menses is actually the end of an arbitrarily defined men- Third Phase of Menstrual Cycle (Ischemic). If fertilization strual cycle. Because it is the only external marker of the does not occur, the corpus luteum in the ovary begins to cycle, however, the first day of menstrual flow is used to mark regress after 8 to 10 days. As it regresses, the production of the beginning day of a new menstrual cycle. 102 UNIT 2 The Nursing Role in Preparing Families for Childbearing and Childrearing 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 en- dometrial 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 supplement to prevent iron deple- tion during their menstruating years. In women who are beginning menopause, menses may typically consist of a few days of spotting before a heavy flow, or a heavy flow followed by a few days of spotting, because progesterone withdrawal is more sluggish or tends to “stair- case” rather than withdraw smoothly. ✔Checkpoint Question 5.4 Suzanne Matthews typically has a menstrual cycle of 34 days. A She tells you she had sexual intercourse on days 8, 10, 15, and 20 of her last cycle. Which is the day on which she most likely conceived? a. Day 8 b. Day 10 c. Day 15 d. Day 20 Cervix The mucus of the uterine cervix, as well as the uterine body, changes each month during the menstrual cycle. During the first half of the cycle, when hormone secretion from the ovary is low, cervical mucus is thick and scant. Sperm sur- vival in this type of mucus is poor. At the time of ovulation, when the estrogen level is high, cervical mucus becomes thin B and copious. Sperm penetration and survival at the time of FIGURE 5.14 (A) A ferning pattern of cervical mucus occurs ovulation in this thin mucus are excellent. As progesterone with high estrogen levels. (B) Incomplete ferning during secre- becomes the major influencing hormone during the second tory phase of cycle. (From Scott, J. R.. Danforth’s ob- half of the cycle, cervical mucus again becomes thick and stetrics and gynecology [6th ed.]. Philadelphia: JB Lippincott.) sperm survival is again poor. Women can analyze cervical mucus changes to help plan midpoint of a menstrual cycle is another way to demonstrate coitus to coincide with ovulation if they want to increase that high levels of estrogen are being produced and, by im- their chance of becoming pregnant or plan to avoid coitus at plication, that ovulation is about to occur. A woman can do the time of ovulation to prevent pregnancy (see Chapter 6). this herself by stretching a mucus sample between thumb and finger, or it can be tested in an examining room by smearing Fern Test. When high levels of estrogen are present in the a cervical mucus specimen on a slide and stretching the body, as they are just before ovulation, the cervical mucus mucus between the slide and coverslip (Fig. 5.15). forms fernlike patterns caused by the crystallization of sodium chloride on mucus fibers when it is placed on a glass Education for Menstruation slide and allowed to dry. This pattern is known as arbor

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