Menstrual cycle ovulation

Consider the menstrual cycle, ovulation, and the possibility of pregnancy before beginning treatment. 

The crypsis is further enhanced by there being a responsive element to ovulation. From about day 5 of the menstrual cycle, ovulation seems to be on hold while the woman meets and assesses males, including perhaps collecting sperm (Clark and Zarrow 1971 Jochle 1975 Baker 1996). This phase may last anything from 2-21 days. Depending on events during this phase ovulation may or may not occur. It seems particularly likely to occur a couple of days after the female has a brief opportunity to collect sperm from an attractive male. 

Taking the contraceptive hormones provides health benefits not related to contraception, such as regulating the menstrual cycle and decreased blood loss, and incidence of iron deficiency anemia, and dysmenorrhea Health benefits related to the inhibition of ovulation include a decrease in ovarian cysts and ectopic pregnancies. hi addition, there is a decrease in fibrocyctic breast disease, acute pelvic inflammatory disease endometrial cancer, ovarian cancer, maintenance of bone density, and symptoms related to endometriosis in women taking contraceptive hormones. Newer combination contraceptives such as norgestimate and ethinyl estradiol... 

The female menstrual cycle is divided into four functional phases follicular, ovulatory, luteal, and menstrual.6 The follicular phase starts the cycle, and ovulation generally occurs on day 14. The luteal phase then begins and continues until menstruation occurs.6 The menstrual cycle is regulated by a negative-feedback hormone loop between the hypothalamus, anterior pituitary gland, and ovaries6 (Fig. 45-1). 

The NuvaRing is a unique transvaginal delivery system that provides 15 meg ethinyl estradiol and 120 meg etonogestrel for the prevention of ovulation. The NuvaRing is inserted into the vagina on or before day 5 of the menstrual cycle and is removed... 

Therapeutic modalities for amenorrhea are targeted at restoring the normal menstrual cycle. The goals of treatment are to preserve bone density, prevent bone loss, and restore ovulation, thus improving fertility as desired. Amenorrhea resulting from conditions contributing to hypoestrogenism also may affect quality of life via the induction of hot flashes (premature ovarian failure), dyspareunia, and in prepubertal females, lack of secondary sexual characteristics and absence of menarche. 

The first-line therapeutic options for PMDD include the selective serotonin reuptake inhibitors (SSRIs) such as fluoxetine, fluvoxamine, sertraline, paroxetine, and citalopram. These agents can be given either continuously or only during the luteal phase of the menstrual cycle, i.e., initiated at the time of ovulation and discontinued on the first day of menses. 

The median length of the menstrual cycle is 28 days (range 21 to 40). The first day of menses is day 1 of the follicular phase. Ovulation usually occurs on day 14 of the menstrual cycle. After ovulation, the luteal phase lasts until the beginning of the next cycle. 

The effects of raloxifene in premenopausal women have been analyzed in subjects with normal ovarian function treated with high doses (100 to 400 mg daily) at either different time points of their menstrual cycle or continuously for 4 weeks (Baker et al. 1998). Raloxifene did not prevent ovulation, nor did it alter the length of the menstrual cycle or the day of the LH surge. However, it did stimulate FSH secretion, increase serum estradiol levels, and decrease serum PRL. These results are also similar to those reported for premenopausal women taking tamoxifen (Jordan et al. 1991) and are indicative of some antiestrogenic action at either the hypothalamic and/or pituitary level. 

The results 68% of the women treated with extracts from the follicular phase of the menstrual cycle shortened their own current cycle by an average of 1.7 days. A different 68% of the women treated with extracts from the ovarian phase of the menstrual cycle lengthened their own current cycle by an average of 1.4 days. Finally, underarm extracts taken following ovulation, in the luteal phase, had no effect on the... 

Figure 19.6 A 28-day menstrual cycle. The approximate number of days for menstruation, ovulation and the follicular and luteal phases are shown.

Figure 19.12 Representation of changes in hormone levels during the menstrual cycle. Note that LH peaks about one day before ovulation. Oestrogen has two peaks one in the Luteal phase prior to LH surge and a smaller one in the follicular phase. Progesterone peaks in the follicular phase to stimulate development of endometrium.

Female reproductive organs are also vulnerable to the effects of chemicals, including changes in ovulation or menstrual cycle, decreased implantation of the fertilized egg, or inability to maintain pregnancy. 

Gonadotropins are used to treat infertility in women with potentially functional ovaries who have not responded to other treatments. The therapy is designed to simulate the normal menstrual cycle as far as is practical. A common protocol is daily injections of menotropins for 9 to 12 days, until estradiol levels are equal to that in a normal woman, followed by a single dose of hCG to induce ovulation. Two problems with this treatment are risks of ovarian hyperstimulation and of multiple births. Ovarian hyperstimulation is characterized by sudden ovarian enlargement associated with an increase in vascular permeability and rapid accumulation of fluid in peritoneal, pleural, and pericardial cavities. To prevent such occurrences, ovarian development is monitored during treatment by ultrasound techniques and by measurements of serum levels of estradiol. 

During the follicular phase of the menstrual cycle, one or more follicles are prepared for ovulation. FSH and estrogens are the most important hormones for this developmental process. Complete follicular maturation cannot occur in the absence of LH. Rupture of a mature follicle follows the midcycle peak of LH and FSH by about 24 hours. In humans, usually one mature ovum is released per cycle. During the luteal phase of the menstrual cycle and under the influence of LH, the ovarian granulosa cells of the corpus luteum become vacuolated and accumulate a yellow pigment called lutein. 

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