2. Completing the statements ……. 5. The cessation of menstruation is called Menopause. 7. The inner lining of the uterus is called the Endometrium 8. The organ in which the developing fetus reside is called the Uterus
4. Menopause Menopause refers to the cessation of menstruation due to the depletion of ovarian follicles. Prior to actual ovarian failure, there is a decline in ovulatory function with fewer follicles present. Thus, there is a decline in ovarian estrogen and inhibin production. With falls in ovarian hormones, thee is less negative feedback on the pituitary and hypothalamus, and there is a detectable rise in follicle stimulating hormone and lutenizing hormone. A serum follicle-stimulating hormone (FSH)level is the most sensitive test to confirm menopause. The physiologic period of waning ovarian function is called the climacteric. It generally lasts for several years before atresia(failure of a tubular structure). of all estrogen-producing follicles has occurred. In the United States, menopause is said to occur normally between ages 45 and 55, with the median age being 51. Menopause prior to age 40 is termed premature menopause; after age 55 it is termed late menopause. The onset of menopause is genetically related. It is not related to age at menarche, number of pregnancies, age of last pregnancy, oral contraceptive use, or use of infertility medications. Menopause may occur earlier in women who have a history of tobacco use.
5. Changes Associated with Estrogen Decline Numerous physical and psychological symptoms have been attributed to the decline and discontinuance of ovarian function in midlife. These symptoms include vasomotor symptoms, genital atrophy, osteoporosis, menopausal skin changes, cardiovascular disease, psychiatric disorders, and changes in sexual satisfaction. Vasomotor symptoms, or hot flushes, are the most common perimenopausal symptoms that compel women to seek medical attention. Seventy-five percent of women experience hot flushes. The average duration of these symptoms is two to three years. These symptoms, which include sudden increases in central skin temperature as well as perspiration, are apparently due to deregulation of the temperature- regulating center in the hypothalamus. Both peripheral vasodilatation and perspiration occur. The flush, which generally lasts from a few minutes to 20 minutes, typically is preceded by a premonition - a flash. It is apparently related to decreases in estrogen and inhibin levels, not to absence of estrogen. About one-third of women with vasomotor symptoms find these symptoms severe enough to require medical assistance. Hot flushes may begin before menopause, but generally are more severe after cessation of menses.
6. Genital Atrophy/ Osteoporosis Genital Atrophy. Genital atrophic changes associated with hypoestrogenism are a significant problem for many women. Clinically, the atrophic vagina has a pale appearance and loses its elasticity. The epithelium is thin and friable, and with the lack of colonization by acidophilic bacteria, it no longer produces glycogen. The symptoms related to genital atrophy include vaginal and vulvar itching and burning, dyspareunia, vaginal bleeding, dysuria, urinary frequency, and urinary frequency, and urinary urgency. The most effective therapy for atrophic vaginitis or urethritis is estrogen, which increases the local blood supply and in part reverses these changes. Osteoporosis Osteoporosis, defined as a reduction of bone mass per unit volume, significantly affects more than one-third of older women. Bone strength or bone mineral content is a function of numerous factors that, when deficient, may predispose one to develop osteoporosis. Osteoporosis is rare in African-American women, and it is more common in thin Caucasian or Asian women. Osteoporosis may be somewhat less common in women who have maintained healthy lifestyles. Smoking, excessive alcohol use, sedentary lifestyle, and steroid use appear to be contributing factors in women who develop osteoporosis.
7. Cardiovascular Disease/Psychological Disorders Cardiovascular Disease In the United States, heart disease - specifically coronary artery disease (CAD) -is the leading cause of death for postmenopausal women. Numerous epidemiologic studies indicate that hormone replacement, particularly estrogen replacement, after ovarian failure substantially reduces the incidence of coronary artery disease. Ovarian failure may also be an important determining factor in coronary artery disease in women. The incidence of the disease in women prior to menopause is much lower than that in men of the same age. Psychological Disorders A number of symptoms (anxiety, depression, irritability, fatigue, insomnia, emotional liability, and changes in libido) may occur around the time of menopause. The etiology of these symptoms is incompletely understood and appears to be multifactorial. Estrogen decline may indirectly cause or worsen these symptoms by increasing the risk of developing a sleep disturbance and adversely affecting overall feelings of well-being. The use of HRT in menopausal patients has been demonstrated to help improve symptoms such as nervousness, depression, anxiety, and insomnia. In addition, progestin therapy may increase depressive symptoms.
9. Endometrium The endometrium functions as a lining for the uterus, preventing adhesions between the opposed walls of the myometrium, thereby maintaining the patency of the uterine cavity. During the menstrual cycle or estrous cycle, the endometrium grows to a thick, blood vessel-rich, glandular tissue layer. This represents an optimal environment for the implantation of a blastocyst upon its arrival in the uterus. The average endometrium thickness of 6.7mm. During pregnancy, the glands and blood vessels in the endometrium further increase in size and number. Vascular spaces fuse and become interconnected, forming the placenta, which supplies oxygen and nutrition to the embryo and fetus. The endometrium consists of a single layer of columnar epithelium, resting on a layer of connective tissue, which varies in thickness according to hormonal influences - the stroma. Simple tubular uterine glands reach from the endometrial surface through to the base of the stroma, which also carries a rich blood supply of spiral arteries. In a woman of reproductive age, two layers of endometrium can be distinguished. These two layers occur only in endometrium lining the cavity of the uterus, not in the lining of the Fallopian tubes.
10. Endometrium continues…… The functional layer is adjacent to the uterine cavity. This layer is built up after the end of menstruation during the first part of the previous menstrual cycle. Proliferation is induced by estrogen (follicular phase of menstrual cycle), and later changes in this layer are engendered by progestrone from the corpus luteum (luteal phase). It is adapted to provide an optimum environment for the implantation and growth of the embryo. This layer is completely shed during menstruation. The basal layer, adjacent to the myometrium and below the functional layer, is not shed at any time during the menstrual cycle, and from it the functional layer develops.I n the absence of progesterone, the arteries supplying blood to the functional layer constrict, so that cells in that layer become ischaemic and die, leading to menstruation.
11. The Endometrial cycle.. The endometrial lining undergoes cyclic regeneration. The endometrium initially proliferates under the influence of estrogen. However, once ovulation occurs, in addition to estrogen, the ovary will also start to produce progesterone. This changes the proliferative pattern of the endometrium to a secretory lining. Eventually, the secretory lining provides a hospitable environment for one or more blastocysts. If no blastocyst(implantation) is detected, the progesterone level drops and the endometrial lining is either reabsorbed (estrous cycle) or shed (menstrual cycle). In the latter case, the process of shedding involves the breaking down of the lining, the tearing of small connective blood vessels, and the loss of the tissue and blood that had constituted it through the vagina. The entire process occurs over a period of several days. Menstruation may be accompanied by a series of uterine contractions; These help expel the menstrual endometrium. In case of implantation, however, the endometrial lining is neither absorbed nor shed. Instead, it remains as decidua. The decidua becomes part of the placenta; it provides support and protection for the gestation.
12. The Endometrial cycle.. If there is inadequate stimulation of the lining, due to lack of hormones, the endometrium remains thin and inactive. In humans, this will result in amenorrhea. After menopause, the lining is often described as being atrophic. In contrast, endometrium that is chronically exposed to estrogens, but not to progesterone, may become hyperplastic. In humans, the cycle of building and shedding the endometrial lining lasts an average of 28 days. Its formation is sometimes affected by seasons, climate, stress, and other factors. The endometrium itself produces certain hormones at different points along the cycle. This affects other portions of the reproductive system.
14. Uterus The Uterus is a hollow, thick-walled, muscular organ situated deeply in the pelvic cavity between the bladder and rectum. Into its upper part the uterine tubes open, one on either side, while below, its cavity communicates with that of the vagina. When the ova are discharged from the ovaries they are carried to the uterine cavity through the uterine tubes. If an ovum be fertilized it imbeds itself in the uterine wall and is normally retained in the uterus until prenatal development is completed, the uterus undergoing changes in size and structure to accommodate itself to the needs of the growing embryo. After parturition the uterus returns almost to its former condition, but certain traces of its enlargement remains. The uterus measures about 7.5 cm. in length, 5 cm. in breadth, at its upper part, and nearly 2.5 cm. in thickness; it weighs from 30 to 40 gm. It is divisible into two portions. On the surface, about midway between the apex and base, is a slight constriction, known as the isthmus, and corresponding to this in the interior is a narrowing of the uterine cavity, the internal orifice of the uterus. The portion above the isthmus is termed the body, and that below, the cervix. The part of the body which lies above a plane passing through the points of entrance of the uterine tubes is known as the fundus.
15. Uterus continues The uterus provides structural integrity and support to the bladder, bowel, pelvic bones and organs. The uterus helps separate and keep the bladder in its natural position above the pubic bone and the bowel in its natural configuration behind the uterus. The uterus is continuous with the cervix, which is continuous with the vagina, much in the way that the head is continuous with the neck, which is continuous with the shoulders. It is attached to bundles of nerves, and networks of arteries and veins, and broad bands of ligaments such as round ligaments, cardinal ligaments, broad ligaments, and uterosacral ligaments. The uterus is essential in sexual response by directing blood flow to the pelvis and to the external genitalia, including the ovaries, vagina, labia, and clitoris. The uterus is needed for uterine orgasm to occur. The reproductive function of the uterus is to accept a fertilized ovum which passes through the utero-tubal junction from the fallopian tube. It then becomes implanted into the endometrium, and derives nourishment from blood vessels which develop exclusively for this purpose. The fertilized ovum becomes an embryo, attaches to a wall of the uterus, creates a placenta, and develops into a fetus (gestates) until childbirth. Due to anatomical barriers such as the pelvis, the uterus is pushed partially into the abdomen due to its expansion during pregnancy. Even during pregnancy the mass of a human uterus amounts to only about a kilogram (2.2 pounds).
