Clomiphene citrate for unexplained subfertility in women.

OBJECTIVES

Clomiphene citrate appears to increase ovulation in women with oligo-ovulatory subfertility. It may also work in women with unexplained subfertility, perhaps by correcting an unidentifiable ovulatory dysfunction. The objective of this review was to assess the effects of clomiphene citrate in women with unexplained subfertility.

SEARCH STRATEGY

The Cochrane Subfertility Review Group specialised register of controlled trials was searched".

SELECTION CRITERIA

Randomised trials of clomiphene citrate (doses of 50 to 250 milligrams per day up to 10 days) compared to placebo or no treatment in women with unexplained subfertility.

DATA COLLECTION AND ANALYSIS

Trial quality was assessed and data were extracted independently by two reviewers.

MAIN RESULTS

Five studies were included. Four trials were of crossover design, and quality of the randomisation was variable. Compared to placebo, clomiphene citrate was associated with an increase in pregnancy rates. The odds ratio for pregnancy per patient was 2.38 (95% confidence interval 1.22 to 4.62). The odds ratio of pregnancy per cycle was 2.5 (95% confidence interval 1.35 to 4.62).

REVIEWER'S CONCLUSIONS: Clomiphene citrate appears to modestly improve pregnancy rates in women with unexplained subfertility. However adverse effects include a possible ovarian cancer risk and risk of multiple pregnancy.