Module 2 - Topic 1 PDF

Summary

This document discusses the dimensions and influences of human sexuality, reviewing anatomy and physiology of the reproductive system. It also outlines common methods for reproductive life planning, examining ovulation and potential impacts on future pregnancies, along with contraceptive use. The document explains the biological, psychological, and socio-cultural dimensions of human sexuality.

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Module II Reproductive and Sexual Health Topic # Topic Title Time Duration 1 Human Sexuality...

Module II Reproductive and Sexual Health Topic # Topic Title Time Duration 1 Human Sexuality 4 hours 2 Responsible Parenthood 4 hours Module II discusses the dimensions and what influences human sexuality. It reviews anatomy and physiology of the reproductive system. It also outlines common methods available for reproductive life planning including physiologic actions and potential impacts on future pregnancies. The module examines the ovulation and the side effects of an ovulation suppressing agent. The Medical Eligibility Criteria for Contraceptive Use is introduced to help students understand the methods that are appropriate for a certain couple. TOPIC 1 Learning Objectives: After mastering the contents of this module, you should be able to: 1. Describe anatomy and physiology pertinent to reproductive and sexual health. 2. Determine the dimensions of human sexuality. 3. Outline the phases of the menstrual cycle. 4. Explain the sexual response cycle. Human sexuality is a part of your total personality. It encompasses the sexual knowledge, beliefs, attitudes, values, and behaviors of individuals. Its various dimensions include the anatomy, physiology, and biochemistry of the sexual response system; identity, orientation, roles, and personality; and thoughts, feelings, and relationships. The expression of sexuality is influenced by ethical, spiritual, cultural, and moral concerns (SIECUS, 2014). Biological Dimension The biological dimension of our sexuality involves our physical appearance, especially the development of physical sexual characteristics; our responses to sexual stimulation; our ability to reproduce or to control fertility; and our growth and development in general. Although human reproductive function does not begin until puberty, human sexual–erotic functioning begins immediately after birth and last a lifetime. It is important to realize that biological functioning, as it relates to sexuality, is a part of the natural functioning of human beings. These biological aspects also relate to the other dimensions of sexuality, and all the dimensions work together to produce an individual’s total sexuality – which in turn, is part of the total personality (Bruess & Schroeder, 2014) Psychological Dimensions Although sexual activity is definitely physical, it also involves psychology—our sense of being. The noted sexual therapist Dr. Ruth Westheimer has a favorite saying, that sexual behavior “is all between the ears.” A major psychological factor that affects our sexual wellness is body image. A positive body image lends itself to a feeling of overall wellness; a negative self-image can lead to drug abuse (use of steroids or diet pills) or psychological disorders (anorexia, buli-mia, binge eating disorder, or muscle dysmorphia). Socio Cultural Dimension The biological and psychological components of sexuality are affected by society and culture. The socio-cultural dimension of sexuality is the sum of the cultural and social influences that affect our thoughts and actions. Tiefer (1995) promotes the idea of social constructionism, which proposes that sexual identities and experiences are acquired from and influenced and modified by an ever-changing social environment. According to social constructionists, people acquire and assemble meanings, skills, and values from the people around them. This dimension of sexuality is the sum of the cultural influences that affect our thoughts and actions, both historical and contemporary. For example, historical influences become evident when one considers roles of males and females as well as certain customs. Indeed, we are surrounded by social influences on our sexuality. Sexuality Sources of Influences: Religious Influences Religious and spiritual beliefs influence feelings about morality, sexual behavior, premarital sexual behavior, adultery, divorce, contraception, abortion, and masturbation. Religion can also play a role in use or nonuse of medical services related to sexuality. It can even influence the availability of such services when policies allow service providers to refuse to provide services that are against their personal beliefs. For example, a pharmacist might refuse to sell contraceptives because he does not believe in their use. Multicultural Influences Cultures within the United States differ in their views of sexuality. Your ability to respect your sexual partner’s cultural beliefs and feelings will result in a higher level of satisfaction for both of you. First, we must distinguish between ethnic back-ground and ethnicity. A person’s ethnic background is usually determined by birth and is related to country of origin, native language, race and religion. Ethnicity refers to the degree of identification an individual feel with a particular ethnic group. Socioeconomic Influences Socioeconomic status and education also influence sexual attitudes and behaviors, at least within the same ethnic group. Examples of this influence include low-income individuals often thinking and acting differently than middle-class individuals, being more likely to engage in sexual intercourse at an earlier age, and having children outside of marriage. Educational levels also seem to influence sexual behavior. Socioeconomic status influences more than just sexual activities. The poor have less access to proper health care, birth control, care during pregnancy, day care for children and positive sexual role models. Ethical Influences The ethics of sexuality involves questioning the way we treat ourselves and other people. Examples of sexually oriented ethical dilemmas include the following: Should I or should I not participate in a certain sexual behavior? Is it ethical to use a prostitute? Is it ethical not to disclose my full sexual history to a new partner? Is it ethical to engage in sexual behaviors with a person who is underage? Is it ethical to use a position of power to obtain sexual partners? Ethical decision-making underscores the importance of taking responsibility for your sexual wellness. Media Influences It has long been recognized that the media help shape public attitudes on many topics— especially sexuality, sex roles, and sexual behaviors. The depictions of sexuality we encounter in the media are there mainly to entertain and sell products. Consequently, the media do not provide us with realistic depictions. Television shows are filled with portrayals of sexual activity and “double-meaning” comments. The music industry has countless sexual images. Listen to the words of many currently popular songs and you will hear the sexual content. Magazines, tabloids, many online sources, and books contribute to the many sexual themes that bombard us. Some people have argued that, if they would so choose, the media could promote sexual health by communicating accurate information and portraying realistic situations. For example, they might show effective communication about sexuality and relationships, interactions as verbally and physically respectful, more examples of responsible sexual activity, more instances where healthy sexual encounters are anticipated and not last-minute responses to the heat of passion, and the importance of having good information and using contraceptives and condoms to prevent unwanted pregnancies and diseases. Political Influences Even public policy affects our sexual behavior. Even political elections—including choosing elected officials and voting on ballot initiatives—can have a profound effect on policies and on thinking about human sexuality. Consider the political ramifications of election results. Political parties can have a profound effect on policies and on thinking about human sexuality. Issues related to sexuality that are commonly discussed in political circles includes abortion, LGBTQ rights, medical advances like genetic engineering and stem cell research. We can be confident that politics will continue to influence thinking about human sexuality and vice versa. Definition of Terms: The unitive and procreative aspects of the sexual act are inseparable. All marital acts must respect both the unitive and procreative purposes of the marital act. The unitive meaning is ordered toward the marital meaning. Marriage is when a man and woman unite as “one flesh.” Sex is unitive  The unitive meaning is ordered toward the marital meaning. In fact, this union is necessary for the consummation of the marriage. And the unitive meaning is ordered toward the procreative meaning.  Procreation is the creation of a new human person, by the act of sexual intercourse, by a man and a woman. Marriage needs to be open to the possibility of having children. Sex is procreative.  Sexual health is the ability to enjoy and express one’s sexuality free from the risks of sexually transmitted infections, unwanted pregnancy, coercion, violence, and discrimination.  Sexual orientation - a term used to describe your pattern of emotional, romantic or sexual attraction. Sexual orientation may include attraction to the same gender (homosexuality), a gender different than your own (heterosexuality), both men and women (bisexuality), all genders (pansexual), or neither (asexuality).  Sexual identity describes how a person identifies related to their sexual orientation Hence a man who exclusively prefers women will usually have a straight or heterosexual sexual identity, and a woman who exclusively prefers women usually a lesbian or homosexual sexual identity.  Self Concept – mental image or picture of self; includes body image, subjective self, ideal self and social self.  Body Image – how a person experiences his or her own body.  Gender behaviors, expectations, and responsibilities that are considered appropriate for women (feminine) and men (masculine).  Gender identity is the inner sense a person has of being male or female, which may be the same as or different from sex assigned at birth. Gender identity is your internal and psychological sense of yourself as a woman, a man, both, in between or neither. Only you can determine your gender identity.  Gender expression refers to the behavior a person exhibits, which may or may not be the same as the person’s gender identity or sex assigned at birth.  Gender roles set of perceived behavioral norms associated particularly with males or females, in a given social group or system. For women (feminine) and men (masculine).  Biologic Sex – includes all of the human being’s genetically determined anatomy and physiology, which is also influenced by intrauterine conditions. Reproductive Development - begins at the moment of conception and continues through life. INTRAUTERINE DEVELOPMENT Sex assigned at birth is generally determined at the moment of conception by chromosome information, which is supplied by the sperm that joins with the ovum to create the new life. At about week 12 of intrauterine life, the external genitals begin to develop. In males, penile tissue elongates and the ventral surface of the penis closes to form a urethra. In females, with no testosterone present, the uterus, labia minora, and labia majora form. If, for some reason, testosterone secretion is halted in utero, a chromosomal male could be born with female- appearing genitalia (ambiguous genitalia). PUBERTAL DEVELOPMENT Puberty is the stage of life at which secondary sex changes begin. In most girls, these changes are stimulated when the hypothalamus synthesizes and releases gonadotropinreleasing hormone (GnRH), which then triggers the anterior pituitary to release folliclestimulating hormone (FSH) and luteinizing hormone (LH). FSH and LH are termed gonadotropin (gonad = “ovary”; tropin = “growth”) hormones not only because they begin the production of androgen and estrogen, which in turn initiate secondary sex characteristics, but also because they continue to cause the production of eggs and influence menstrual cycles throughout women’s lives (Eggers, Ohnesorg, & Sinclair, 2014). The Role of Androgen Androgenic hormones are the hormones responsible for muscular development, physical growth, and the increase in sebaceous gland secretions that cause typical acne in both boys and girls during adolescence. In males, androgenic hormones are produced by the adrenal cortex and the testes and, in females, by the adrenal cortex and the ovaries. The level of the primary androgenic hormone, testosterone, is low in males until puberty (between ages 12 and 14 years) when it rises to influence pubertal changes in the testes, scrotum, penis, prostate, and seminal vesicles; the appearance of male pubic, axillary, and facial hair; laryngeal enlargement with its accompanying voice change; maturation of spermatozoa; and closure of growth plates in long bones (termed adrenarche). In girls, testosterone influences enlargement of the labia majora and clitoris and the formation of axillary and pubic hair. The Role of Estrogen When triggered at puberty by FSH, ovarian follicles in females begin to excrete a high level of the hormone estrogen. This increase influences the development of the uterus, fallopian tubes, and vagina; typical female fat distribution; hair patterns; and breast development. It also closes the epiphyses of long bones in girls the same way testosterone closes the growth plate in boys. The beginning of breast development is termed thelarche, which usually starts 1 to 2 years before menstruation. Secondary Sex Characteristics Adolescent sexual development has been categorized into stages (Tanner, 1990). There is wide variation in the time required for adolescents to move through these developmental stages; however, the sequential order is fairly constant. In girls, pubertal changes typically occur as:  Growth spurt  Increase in the transverse diameter of the pelvis  Breast development  Growth of pubic hair  Onset of menstruation  Growth of axillary hair  Vaginal secretions The average age at which menarche (the first menstrual period) occurs is 12.4 years of age (Ledger, 2012). It may occur as early as age 9 years or as late as age 17 years, however, and still be within a normal age range. Irregular menstrual periods are the rule rather than the exception for the first year or two. Menstrual periods do not become regular until ovulation occurs consistently, and this does not tend to happen until 1 to 2 years after menarche. Unlike the production of ova in girls, spermatozoa in boys do not begin in intrauterine life and is not produced in a cyclic pattern; rather, they are produced in a continuous process. The production of ova stops at menopause. In contrast, sperm production continues from puberty throughout the male’s life. Secondary sex characteristics of boys usually occur in the order of:  Increase in weight  Growth of testes  Growth of face, axillary, and pubic hair  Voice changes  Penile growth  Increase in height  Spermatogenesis (production of sperm) Anatomy and Physiology of the Human Reproductive System Male Reproductive System Functions: There are a number of functions that are associated with the male reproductive system:  To produce, maintain and transport the sperm (the male reproductive cells) and the fluid semen;  To eject sperm from the penis;  To manufacture and secrete the male sex hormones External and Internal Male Reproductive System External: Testes - are small oval-shaped organs measuring approximately 5 cm long and 2.5 cm wide with a layer of serous fibrous connective tissue surrounding them. There are three layers that cover the testes:  tunica vaginalis  tunica albuginea  tunica vasculosa The key functions of the testes are to:  produce sperm (spermatozoa);  produce the male sex hormones (e.g. testosterone) Scrotum - The scrotal sac is likened to a loose bag of skin hanging between the thighs, anterior to the anus; this is a supporting structure that is suspended from the root of the penis. On the outside the scrotum usually appears as a single sac of skin that is separated into two portions by a ridge in the middle known as the raphe. From the inside the scrotum is divided into two sacs separated by a scrotal septum with a testicle in each. The scrotum assists with control of the temperature of the testes. Penis - the male copulatory organ. The penis encloses the urethra and is a highly vascular organ. This organ is the passageway for excretion of urine as well as the ejaculation of semen. The penis has a shaft and a tip known as the glans, and in the uncircumcised male this is covered by the prepuce (also called the foreskin). The penis is cylindrical in shape, composed of three cylindrical masses of tissues. The three columns of erectile tissue in the penis are the shaft, the corpora cavernosa and the corpus spongiosum. The attached portion of the penis is known as the root, and the freer moving part is called the shaft or the body. The penis is usually flaccid and hangs down, but during sexual excitation it becomes erect (an erection), swollen, engorged with blood, firmer and straighter. These changes occur as a result of blood filling the erectile tissue, permitting the penis to penetrate the vagina and deposit sperm (ejaculation) as close to the site of fertilization as possible. Internal: Epididymis - (plural epididymides) is an approximately 4 cm long comma-shaped duct. It lies on the posterior lateral aspect of the testes. The organ is composed of a highly coiled duct. This duct leads to a larger and more muscular tube called the vas deferens; the vas deferens enters the pelvic cavity. Within the epididymis the sperm are matured further, being prepared to become more motile so that they can eventually fertilize the ovum. It takes approximately 14 days of full maturation for this to occur (Jenkins and Tortora, 2012). Sperm is stored in the epididymis and is released via peristaltic activity as the smooth muscle contracts during sexual arousal, moving the sperm along the epididymis into the vas deferens. Sperm stored in the epididymis can remain there for several months; those sperm that are not ejaculated are eventually reabsorbed. Vas deferens, ejaculatory duct and spermatic cord - (plural vasa deferentia), or the ductus deferens, as it enters the pelvic cavity is less convoluted than the epididymis; the diameter is also larger, and the length of the vas deferens is approximately 45 cm (Tortora and Derrickson, 2012). This tube contains ciliated epithelium with a thick muscle layer. The vas deferens runs from the anterior aspect of the scrotal sac as a pair of tubes via the inguinal canal into the pelvic cavity. Between the scrotal sac and the inguinal canal is a tube that the vas deferens runs through; this tube contains the blood vessels and nerves and is called the spermatic cord (Colbert et al., 2012). Seminal Vesicles The seminal vesicles are two convoluted pouches that lie along the lower portion of the bladder and empty into the urethra by ejaculatory ducts. These glands secrete a viscous alkaline liquid with a high sugar, protein, and prostaglandin content. Sperm become increasingly motile because this added fluid surrounds them with a more favorable pH environment. Prostate gland - The prostate is a single doughnut-shaped gland approximately the size of a walnut, measuring about 4 cm. It goes around the urethra under the urinary bladder and is made of 20–30 glands enclosed in smooth muscle (Marieb, 2012). The function of the prostate gland is not well understood (Laws, 2006). The prostate consists of three distinct zones:  the central zone  the peripheral zone  the transition zone Secretions of the prostate gland compose approximately one-third of the volume of the semen; the fluid helps sperm motility and to maintain viability. Prostatic fluid is slightly acidic (pH 6.5). Prostatic secretions enter the urethra via a number of ducts during ejaculation. Bulbourethral Glands Two bulbourethral, or Cowper’s, glands lie beside the prostate gland and empty by short ducts into the urethra. They supply one more source of alkaline fluid to help ensure the safe passage of spermatozoa. Semen, therefore, is derived from the prostate gland (60%), the seminal vesicles (30%), the epididymis (5%), and the bulbourethral glands (5%). Urethra The urethra is a hollow tube leading from the base of the bladder, which, after passing through the prostate gland, continues to the outside through the shaft and glans of the penis. It is about 8 in. (18 to 20 cm) long. Like other urinary tract structures, it is lined with mucous membrane. THE FEMALE REPRODUCTIVE ORGAN The female reproductive system is designed to produce ova, receive the penis during intercourse and the sperm that has been ejaculated, store, contain and nourish a fetus, and feed the newborn after birth with breast milk. The breasts are also a part of the female reproductive organs. Breasts The breasts are dome-shaped protrusions that differ in size between individuals; they are also sometimes called the mammary glands. They are external accessory sexual organs in the female. There are several milk-producing glands located within the breast. A hormone called prolactin controls the production of milk. The breasts are located between the third and seventh ribs on the anterior aspect chest wall. The breasts are supported by the pectoral muscles and are provided with a rich supply of nerves, blood vessels and lymph (see Figure 12.14). A pigmented area known as the areola is situated a little below the centre of each breast and contains glands that secrete sebum – a thick substance composed of fat and cell debris (sebaceous glands), – and a nipple. The nipple is usually protruding, becoming erect in response to cold and stimulation. The breasts are made of adipose (fat) tissue, fibrous connective tissue and glandular tissue There are bands of fibrous tissue that support the breast and extend from the outer breast tissue to the nipple, dividing the breast into 15 to 25 lobes. The lobes are comprised of alveolar glands joined by ducts that open out on to the nipple. The primary genitalia in the female are the ovaries, the secondary genitalia are the fallopian tubes, uterus and vagina; the vulva is the external genitalia. FEMALE EXTERNAL GENITALIA External (Vulva – covering in Latin) genitalia: Mons Veneris The mons veneris is a pad of adipose tissue located over the symphysis pubis, the pubic bone joint. 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. Labia Minora The labia minoraImmediately posterior to the mons veneris spread two hairless folds of connective tissue, the labia minora. Before menarche, these folds are fairly thin; by childbearing age, they have become firm and full; and after menopause, they atrophy and again become much smaller. Normally, the folds of the labia minora are pink in color; the internal surface is covered with mucous membrane, and the external surface is covered with skin. The area is abundant with sebaceous glands, so localized sebaceous cysts may occur here. Women who perform monthly vulvar examinations are able to detect infection or other abnormalities of the vulva such as sebaceous cysts or herpes lesions. Labia Majora The labia majora are two folds of tissue, fused anteriorly but separated posteriorly, which are positioned lateral to the labia minora and composed of loose connective tissue covered by epithelium and pubic hair. The labia majora serve as protection for the external genitalia; they shield the outlets to the urethra and vagina. Trauma to the area, such as occurs from childbirth or rape, can lead to extensive edema formation because of the looseness of the connective tissue base. Other External Organs Vestibule is the flattened, smooth surface inside the labia. The openings to the bladder (the urethra) and the uterus (the vagina) both arise from this space. Clitoris is a small (approximately 1 to 2 cm), rounded organ of erectile tissue at the forward junction of the labia minora. It’s covered by a fold of skin, the prepuce; is sensitive to touch and temperature; and is the center of sexual arousal and orgasm in a woman. Arterial blood supply for the clitoris is plentiful. When the ischiocavernosus muscle surrounding it contracts with sexual arousal, the venous outflow for the clitoris is blocked and this leads to clitoral erection. Two Skene glands (paraurethral glands) are located on each side of the urinary meatus; their ducts open into the urethra. Bartholin glands (vulvovaginal glands) are located on each side of the vaginal opening with ducts that open into the proximal vagina near the labia minora and hymen. Secretions from both of these glands help to lubricate the external genitalia during coitus. The alkaline pH of their secretions also helps to improve sperm survival in the vagina. If the Skene glands or the Bartholin glands (the most common site) become infected, they swell, feel tender, and produce a serous discharge. Fourchette is the ridge of tissue formed by the posterior joining of the labia minora and the labia majora. This is the structure that sometimes tears (laceration) or is cut (episiotomy) during childbirth to enlarge the vaginal opening. Posterior to the fourchette is the perineal muscle (often called the perineal body). Because this is a muscular area, it stretches during childbirth to allow enlargement of the vagina and passage of the fetal head. Many exercises suggested for pregnancy (such as Kegel exercises, squatting, and tailor sitting) are aimed at making the perineal muscle as flexible as it can be to allow for optimal expansion during birth and to prevent tearing of this tissue. Hymen is a tough but elastic semicircle of tissue that covers the opening to the vagina during childhood. It is often torn during the time of first sexual intercourse. However, because of the use of tampons and active sports participation, many girls who have not had sexual relations can also have torn hymens at the time of their first pelvic examination. Occasionally, a girl has an imperforate hymen, or a hymen so complete that it does not allow for the passage of menstrual blood from the vagina (hematocolpometra) or for sexual relations until it is surgically incised (Fischer & Kwan, 2014). Vulvar Blood Supply The blood supply of female external genitalia is mainly from the pudendal artery and a portion is from the inferior rectus artery. Venous return is through the pudendal vein. Pressure on this vein by the fetal head during pregnancy can cause extensive back pressure and development of varicosities (distended veins) in the labia majora and in the legs. A disadvantage of this rich blood supply is that trauma to the area, such as occurs from pressure during childbirth or a bicycle seat injury, can cause large hematomas. An advantage is that it contributes to the rapid healing of any tears in the area after childbirth or other injury (Huether & McCance, 2012). Vulvar Nerve Supply The anterior portion of the vulva derives its nerve supply from the ilioinguinal and genitofemoral nerves (L1 level). The posterior portions of the vulva and vagina are supplied by the pudendal nerve (S3 level). Such a rich nerve supply makes the area extremely sensitive to touch, pressure, pain, and temperature. Luckily, at the time of birth, normal stretching of the perineum causes a temporary loss of sensation to the area, limiting the amount of local pain felt during childbirth. FEMALE INTERNAL GENITALIA Anterior View Ovaries The ovaries are approximately 3 cm long by 2 cm in diameter and 1.5 cm thick, or the size and shape of almonds. They are grayish-white and appear pitted, with minute indentations on the surface. The ovaries are located close to and on both sides of the uterus in the lower abdomen. Normally, they lie so low they cannot be located by abdominal palpation. The function of the two ovaries is to produce, mature, and discharge ova (the egg cells). In the process of producing ova, the ovaries also produce estrogen and progesterone and initiate and regulate menstrual cycles. If the ovaries are removed before puberty (or are nonfunctional), the resulting absence of estrogen normally produced by the ovaries prevents maturation and maintenance of secondary sex characteristics; in addition, pubic hair distribution will assume a more male than female pattern. The ovaries are held suspended and in close contact with the ends of the fallopian tubes by three strong ligaments that attach both to the uterus and the pelvic wall. Ovaries are unique among pelvic structures in that they are not covered by a layer of peritoneum. Because they are not covered this way, ova can readily escape from them and enter the uterus by way of the fallopian tubes. Because they are suspended in position rather than being firmly fixed, an abnormal tumor or cyst growing on them can enlarge to a size easily twice that of the organ before pressure on surrounding organs or the ovarian blood supply leads to symptoms of compression. This is the reason ovarian cancer continues to be one of the leading causes of death from cancer in women (the tumor can grow without symptoms for an extended period) (Sundar, Neal, & Kehoe, 2015). Fallopian Tubes The fallopian tubes arise from each upper corner of the uterine body and extend outward and backward until each opens at its distal end, next to an ovary. Fallopian tubes are approximately 10 cm long in a mature woman. Their function is to convey the ovum from the ovaries to the uterus and to provide a place for fertilization of the ovum by sperm. Although a fallopian tube is a smooth, hollow tunnel, it is anatomically divided into four separate parts: 1. The most proximal division, the interstitial portion, is the part of the tube that lies within the uterine wall. This portion is only about 1 cm in length; its lumen is only 1 mm in diameter. 2. The next distal portion is the isthmus. This is about 2 cm in length and, like the interstitial tube, remains extremely narrow. This is the portion of the tube that is cut or sealed in a tubal ligation, or tubal sterilization procedure. 3. The ampulla is the third and also the longest portion of the tube. It is about 5 cm in length and is the portion of the tube where fertilization of an ovum usually occurs. 4. The infundibular portion is the most distal segment of the tube. It is about 2 cm long, funnel shaped, and covered by fimbria (small hairs) that help to guide the ovum into the fallopian tube. The lining of the fallopian tubes is composed of a mucous membrane, which contains both mucus-secreting and ciliated (hair-covered) cells. Beneath this mucous lining are connective tissue and a circular muscle layer. The muscle layer is important because it is able to produce peristaltic motions that help conduct the ovum the length of the tube (probably also aided by the action of the ciliated lining and the mucus, which acts as a lubricant). The mucus produced may also serve as a source of nourishment for the fertilized egg because it contains protein, water, and salts. Because the fallopian tubes are open at their distal ends, a direct pathway exists from the external genital organs, through the vagina to the uterus and tubes, to the peritoneum. This open pathway is what makes conception possible. It also, however, can lead to infection of the peritoneum (peritonitis) if germs spread from the perineum through the uterus and tubes to the pelvic cavity. For this reason, clean technique must be used during pelvic examinations. During labor and birth, vaginal examinations are done with sterile technique to ensure no organisms can enter by this route. Uterus The uterus is a hollow, muscular, pear-shaped organ located in the lower pelvis, posterior to the bladder and anterior to the rectum. During childhood, it is about the size of an olive; the cervix is the largest portion and the uterine body is the smallest part. When a girl reaches about 8 years of age, an increase in the size of the organ begins. This growth is so slow, however, the young woman is closer to 17 years old before the uterus reaches its adult size and changes its proportions so that the body cavity, not the cervix, is its largest portion. Small uterine size may be a contributing factor to the number of low–birth-weight babies typically born to adolescents younger than this age (March of Dimes Foundation, 2012). With maturity, a uterus is about 5 to 7 cm long, 5 cm wide, and, in its widest upper part, 2.5 cm deep. In a non-pregnant state, it weighs approximately 60 g. The function of the uterus is to receive the ovum from the fallopian tube; provide a place for implantation and nourishment; furnish protection to a growing fetus; and, at maturity of the fetus, expel it from a woman’s body. After a pregnancy, the uterus never returns to exactly its non-pregnant size but remains approximately 9 cm long, 6 cm wide, 3 cm thick, and 80 g in weight. Divisions of the Uterus: the body or corpus, the isthmus, and the cervix 1. The body of the uterus is the uppermost part and forms the bulk of the organ. The lining of the cavity is continuous with the fallopian tubes, which enter at its upper aspects (the cornua). The portion of the uterus between the points of attachment of the fallopian tubes is termed the fundus. During pregnancy, the body of the uterus is the portion of the structure that expands to contain the growing fetus. The fundus is the portion that can be palpated abdominally to determine the amount of uterine growth during pregnancy, to measure the force of uterine contractions during labor, and to assess that the uterus is returning to its non-pregnant state after childbirth. 2. The isthmus is a short segment between the body and the cervix. In the non-pregnant uterus, it is only 1 to 2 mm in length. During pregnancy, this portion also enlarges greatly to aid in accommodating the growing fetus. It is the portion where the incision most commonly is made when a fetus is born by a cesarean birth. 3. The cervix is the lowest portion of the uterus. It represents about one third of the total uterine size and is approximately 2 to 5 cm long. About 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 of the cervix and isthmus is the internal cervical os; the distal opening to the vagina is the external cervical os. The level of the external os is at the level of the ischial spines (an important relationship in estimating the level of the fetus in the birth canal at the time of birth). Uterine and Cervical Coats The uterine wall consists of three separate coats or layers of tissue: 1. The endometrium, an inner layer of mucous membrane 2. The myometrium, a middle layer of muscle fibers 3. The perimetrium, an outer layer of connective tissue The endometrium layer of the uterus consists of two layers of cells and is the one important for menstrual function. The cell layer closest to the uterine wall, the basal layer, remains stable, uninfluenced by hormones. In contrast, the inner glandular layer is dramatically influenced by both estrogen and progesterone. It grows and becomes so thick and responsive each month under the influence of estrogen and progesterone that it becomes capable of supporting a pregnancy. If pregnancy does not occur, this is the layer that is shed as the menstrual flow. The mucous membrane that lines the cervix is termed the endocervix. Continuous with the endometrium, these cells are also affected by hormones, although their changes are more subtle. A responsibility of such cells is to secrete mucus to provide an alkaline, lubricated surface to reduce the acidity of the upper vagina and to aid the passage of spermatozoa 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 many as 700 ml of mucus per day are produced; at the point estrogen is at its lowest level, only a few milliliters are produced. During pregnancy, so much mucus is produced, the endocervix becomes plugged with mucus, forming a seal to keep out ascending infections (the operculum). Both the lower outer surface of the cervix and the internal cervical canal are lined not with a mucous membrane but with a stratified squamous epithelium, similar to that lining the vagina. Locating the point at which this tissue changes from epithelium to mucous membrane (squamocolumnar junction) is important when obtaining a Papanicolaou smear (a test for cervical cancer) because this tissue interface is most dynamic in cellular growth and is often the origin of cervical cancer (Gueye & Diaz- Montes, 2015). The myometrium, or muscle layer of the uterus, is composed of three interwoven layers of smooth muscle, the fibers of which are arranged in longitudinal, transverse, and oblique directions. This intertwining network of fibers is what offers extreme strength to the organ so when the uterus contracts at the end of pregnancy to expel the fetus, equal pressure is exerted at all points throughout the cavity. Another function of the myometrium is to constrict the fallopian tubes at the point they enter the fundus, preventing regurgitation of menstrual blood into the tubes. The myometrium also holds the internal cervical os closed during pregnancy to prevent a preterm birth. After childbirth, the interlacing network of fibers is able to constrict the blood vessels coursing through the layers, thereby limiting the amount of blood loss. Myomas, or benign fibroid (leiomyoma) tumors that can interfere with conception or birth, arise from the myometrium (Huether & McCance, 2012). The purpose of the perimetrium, the outermost layer of the uterus, is to add further strength and support to the organ. Uterine Blood Supply The large descending abdominal aorta divides to form two iliac arteries; these then form the hypogastric arteries and the uterine arteries, which supply the uterus. Because the uterine blood supply is not far removed from the aorta this way, it is guaranteed to be copious and adequate to supply the growing needs of a fetus. As an additional guarantee that enough blood will be available, after supplying the ovaries with blood, the ovarian artery (a direct subdivision of the aorta) joins the uterine artery and adds more blood to the uterus. SEXUAL RESPONSE CYCLE Human sexual response is described as a cycle with four discrete stages: excitement, plateau, orgasm, and resolution. Whether stages are felt as separate steps this way or blended into one smooth process of desire, arousal, and orgasm is individualized. (Masters, Johnson, & Kolodny,1998) Sexual Response Cycle 1. Excitement (also called arousal). This stage, which is characterized by the body’s initial response to feelings of sexual desire, may last from minutes to several hours. 2. Plateau. This stage, the highest point of sexual excitement, generally lasts between 30 seconds and three minutes. 3. Orgasm. This stage, the peak of the plateau stage and the point at which sexual tension is released, generally lasts for less than a minute. 4. Resolution. The duration of this stage—the period during which the body returns to its pre- excitement state—varies greatly and generally increases with age. Menstrual Cycle – begins on the first day of menstrual bleeding and ends on the day before menstrual bleeding begins again. CHARACTERISTICS OF NORMAL MENSTRUAL CYCLES  The length of a woman’s menstrual cycle can normally vary a few days from cycle to cycle. Average flow 2 – 7 days ranges of 1 – 9 days not abnormal  Interval between cycles – average 28 days; cycles of 23 – 35 days not unusual  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 is similar to that of marigolds.  Menarche – first occurrence of menstruation. Average at onset, 12.4 years; average range, 9 – 17 years  Menopause is the cessation of menstrual cycles  Normal Sperm Analysis: Count 60million/ml; motility 60%; volume 1-6ml per ejaculate; ph 7.2-7.8  Under optimal conditions: 3-5 days lifespan of sperm Phases of Menstrual Cycle 1. Pre – ovulatory Phase (Follicular Phase) – cervix is relatively close  On the first day of the menstrual cycle, estrogen and progesterone levels are low. This causes the shedding of the endometrium as menstrual bleeding.  The low levels of estrogen and progesterone stimulates the brain to produce Follicle Stimulating Hormone (FSH). FSH stimulates the follicles in the ovary to mature. One of these follicles will later further mature to be released during ovulation.  The maturing follicles in the ovary produce estrogen. As the follicles mature further, the estrogen levels increase.  Estrogen causes: endometrium to thicken by cell multiplication and proliferation - Production of mucus to become increasingly wet and lubricated 2. Ovulatory Phase  When estrogen level peak, the brain is stimulated to produce Luteinizing Hormone (LH). This sudden increase of LH causes the release of the mature ovum, a process called ovulation.  Ovulation usually occurs 12-16 days before the onset of the next menstruation.  Once ovulation occurs and the egg has gone into the fallopian tube, it can be fertilized by the male sperm for only up to one day (24 hours).  During this phase: - The lining of the uterus thickens - The egg is mature and is finally released - The cervical mucus is wet, slippery, stretchy and clear. - There is a feeling of vaginal wetness. - The cervix is soft and open. 3. Post-ovulatory Phase (Luteal Phase)– cervix absolutely close  After ovulation, the remaining follicles that underwent initial maturation are transformed into corpus luteum.  The corpus luteum in the ovary produces estrogen in smaller amounts and progesterone in greater amounts. This causes a drop in estrogen levels with higher levels of progesterone.  Progesterone causes the following changes in the woman’s reproductive system. - The cervical mucus becomes pasty and is no longer slippery and stretchy. - The vagina feels dry (this type of mucus does not allow the sperm to travel into the uterus and prevents the sperm from living for more than few minutes to a few hours). - The cervix becomes firm; the cervical opening closes so that the sperm cannot pass through the uterus. - The basal body temperature increases and remains high for the rest of the cycle.  When there is no fertilization, the corpus luteum regresses. As the corpus luteum regresses, the production of progesterone and estrogen decreases.  When estrogen and progesterone levels are low, menstruation occurs.  When fertilization occurs, the fertilized egg produces the Human Chorionic Gonadotropin (HCG) hormone.  Effects of HCG: - The corpus luteum is maintained so that the estrogen and progesterone production is sustained. - Due to sustained levels of estrogen and progesterone, the endometrium is maintained and menstruation is maintained and menstruation does not happen. - The presence of HCG causes the pregnancy test to read positive KEY POINTS FOR REVIEW  The reproductive and sexual organs form early in intrauterine life, and full functioning occurs at puberty.  The female internal organs of reproduction include the ovaries, the fallopian tubes, the uterus, and the vagina.  The female external organs of reproduction include the mons veneris, the labia minora and majora, the vestibule, the clitoris, the fourchette, the perineal body, the hymen, and the Skene and the Bartholin glands.  The male external reproductive structures are the penis, scrotum, and testes. Internal organs are the epididymis, the vas deferens, the seminal vesicles, the ejaculatory ducts, the prostate gland, the urethra, and the bulbourethral glands.  Masters et al. (1998) identified a sexual response cycle consisting of excitement, plateau, orgasm, and resolution stages.  Educating people about reproductive function is an important primary health strategy because it teaches people to better monitor their own health through vulvar or testicular self- examination.  Human sexuality has various dimensions to include the anatomy, physiology, and biochemistry of the sexual response system; identity, orientation, roles, and personality; and thoughts, feelings, and relationships.  The expression of sexuality is influenced by ethical, spiritual, cultural, and moral concerns  Human sexual response is described as a cycle with four discrete stages: excitement, plateau, orgasm, and resolution.  A menstrual cycle is periodic uterine bleeding in response to cyclic hormones.  Menarche is the first menstrual period. Menopause is the end of menstruation.  Menstrual cycles are possible because of the interplay between the hypothalamus, the pituitary gland, the ovaries, and the uterus. References: Silbert-Flagg, JoAnne, Pillitteri, Adelle. (2018). Maternal and Child Health Nursing. Philadelphia: Wolters Kluwer Peate, Ian, Nair, Muralitharan. (2017). Fundamentals of Anatomy and Physiology For Nursing and Health Care Students. West Sussex, UK. John Wiley & Sons, Ltd. Department of Health. Family Planning Competency Based Training (FPCBT) Modules World Health Organization Department of Reproductive Health and Research. (2011) Family Planning: A Global Handbook for Provider https://www.cdc.gov/reproductivehealth/contraception/unintendedpregnancy/pdf/MEC_Slide Set_2016.pdf

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