The effect of clomiphene citrate vs. letrozole on post-coital tests.

PURPOSE: To determine if letrozole is less likely to create a hostile cervical mucus than clomiphene citrate. MATERIALS AND METHODS: Post-coital testing compared at time of peak follicular maturation in women attaining mature follicles in first or second cycle of these two drugs. The study was randomized. Intercourse occurred at least 8-16 hours before. RESULTS: Poor post-coital tests were found in twice the frequency in letrozole cycles than clomiphene citrate cycles. CONCLUSIONS: Despite its shorter half-life, letrozole seems to be as least as likely, if not more, to adversely affect cervical mucus.