The Effect of Clomiphene Citrate and Tamoxifen on the Cervical Mucus

Abstract

The anti-estrogenic effect of clomiphene citrate (CC) and tamoxifen (TMX) on cervical mucus was evaluated in a prospective crossover study. Ten women underwent randomized alternate cyclical treatment with either 100 mg CC, 40 mg TMX daily, or with placebo. The effect of CC, TMX and placebo on serum estradiol (E2), cervical mucus secretion and on the development of ovarian follicles was evaluated. Compared with placebo, treatment with CC and TMX significantly increased the number of mature ovarian follicles on the day of assumed ovulation (p less than 0.05), elevated E2 secretion (p less than 0.05) and decreased cervical score (p less than 0.05). It can be concluded that anti-estrogenic agents reduced the secretion of cervical mucus. However, in most cases, the excessive E2 production due to multiple follicular growth overcomes the anti-estrogenic effect.

Clomiphene Citrate for Women with Unexplained Infertility

“…An increase from 11.0 motile sperm/HPF in the control cycle to 12.2 in the TMX cycle was not significant. Other studies showed no difference between cervical mucous alterations with either CC or TMX [47,51,52] or a decrease in mucus score for TMX compared to placebo [53].…”

Comparison of endocrine and ultrasound profiles during ovulation induction with clomiphene citrate and letrozole in ovulatory volunteer women

“…Acting as an antiestrogen it releases the hypothalamus from the negative feedback effect of endogenous estrogens (E) leading to an increase in both pituitary gonadotropins, FSH and LH, which in turn stimulate follicular growth. A direct antiestrogenic effect on the endometrium and cervical mucus is well documented (4)(5)(6) and this may go some way toward explaining the discrepancy between ovulation and conception rates in treated anovulatory women. Despite this negative effect, CC usually leads to pregnancy in approximately one-third of patients with ovulatory dysfunction undergoing a course of therapy (7).…”