Endometrial thickening

According to results from clinical trials, the agonistic effects of tamoxifen detected in animals were also observed in the human uterus as it produces a trophic effect and an increase in the incidence of endometrial pathology, which is related to endometrial thickening (> 4 mm). Its use seems to be associated with an increase in endometrial cancer, which is related to the length of treatment and the accumulated dose of tamoxifen. Nevertheless, these tumors do not seem to be more aggressive or to have a worse prognosis than those found in women who do not follow this treatment or who receive hormone therapy. 

The endometrial thickening occasionally observed on ultrasound with long-term administration of mifepristone as well as the unique histological changes reported... 

Brenner tumors present rare ovarian tumors that occur at a mean age of 50 years. Brenner tumors constitute l%-3% of ovarian tumors. They are mostly henign, with less than 2% demonstrating borderline or malignant transformation. They are typically small, solid, unilateral ovarian tumors, with 60% of these tumors found under 2 cm in size. Extensive calcification may he observed. The vast majority is discovered incidentally in pathologic specimen of the adnexa. Brenner tumors rarely produce estrogen, and then they may be associated with endometrial thickening [87]. If cystic components are found in Brenner tumors, they may be associated with cystadenomas [88]. Up to 20% of Brenner tumors are associated with mucinous cystadenomas or other epithelial neoplasm (Fig. 9.34). 

Progestins thicken cervical mucus, delay sperm transport, and induce endometrial atrophy. They also block the LH surge and thus inhibit ovulation. Estrogens suppress FSH release, which may contribute to blocking the LH surge, and also stabilizes the endometrial lining and provides cycle control. 

Studies carried out with transvaginal ultrasound (TVU) in postmenopausal women with breast cancer have shown that the endometrium is thickened more frequently in women receiving tamoxifen than in those not treated with the drug. For example, in a transversal study Cohen et al. observed that 94.6% of women treated with tamoxifen and nonsymptomatic from a gynecological point of view had an endometrial thickness > 5 mm, an observation that was present in only 40% of women who did not receive this treatment (Cohen et al. 1994). 

In contrast to the data from that study, other authors have suggested that the increased endometrial thickness found in postmenopausal women treated with tamoxifen is less frequently associated with endometrial abnormalities, even in the presence of a marked thickening and cystic appearance (Achiron et al. 1996 McGonigle et al. 1998). Those ultrasonographic findings often represent sub endometrial processes such as cysts or stromal edema (Bese et al. 1996 Bornstein et al. 1994 Achiron et al. 1995). 

These combined contraceptives seem to function by inducing feedback inhibition of gonadotrophin secretion which, in turn, inhibits the process of ovulation (Chapter 8). They also induce alterations in the endometrial tissue that may prevent implantation. Furthermore, the progestogen promotes thickening of the cervical mucus, which renders it less hospitable to sperm cells. This combination of effects is quite effective in preventing pregnancy. 

The dominant follicle continues to grow and synthesizes estradiol, progesterone, and androgen. Estradiol stops the menstrual flow from the previous cycle, thickens the endometrial lining, and produces thin, watery cervical mucus. FSH regulates aromatase enzymes that induce conversion of androgens to estrogens in the follicle. 

Endometriosis the most common cause of SD. Fragments of endometrial tissue become detached, find their way and adhere to abdominal and pelvic structures outside the uterus. Each piece undergoes the monthly cycle of thickening, shedding and bleeding, causing severe pain. 

The adverse effects associated with clomiphene include thickening of the cervical mucus, which creates a substantial barrier for motile sperm. A postcoital test can be performed to determine if this, in fact, represents an insurmountable hurdle. If so, an lUI is warranted to bypass this cervical challenge. Another adverse effect is endometrial thinning, which is not conducive to embryo implantation if this is the case, additional pharmacological therapies are recommended to thicken the endometrial lining. Other adverse effects include hot flashes and mood swings (95). 

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