Ovulation triggers in anovulatory women undergoing ovulation induction

Anovulation is a common cause for infertility. Drugs used to treat anovulation include selective estrogen receptor modulators, aromatase inhibitors and gonadotrophins. Ovulation triggers are used with these drugs, in order to time intercourse. Ovulation triggers without reliable evidence of oocyte maturity could be inappropriately timed, increase costs and psychological stress. This review evaluates different ovulation triggers used when treating anovulatory women with ovulation inducing agents compared to spontaneous ovulation.

To determine the efficacy of administering an ovulation trigger compared to spontaneous ovulation in anovulatory women being treated with ovulation inducing agents.

We searched the Menstrual Disorders and Subfertility Group Trials Register (August week 1 2007), Cochrane Central Register of Controlled Trials (CENTRAL Cochrane library issue 3 2007) and the electronic databases MEDLINE (1950 July week 4 2007), EMBASE(1980 to week 31 2007) and CINAHL (1982 to August week 1 2007) for studies in all languages.

Randomised controlled trials (RCT).

Two authors independently selected trials, assessed quality and extracted data. Disagreement was resolved by discussion with the third author and by contacting trial authors. Categorical data were analysed using relative risks and their 95% confidence intervals. A random effects model was used in the presence of significant heterogeneity.

Two RCTs comparing urinary hCG versus no treatment in anovulatory women receiving clomiphene citrate were identified. Urinary hCG did not result in increases in the primary outcome of live birth rate over no treatment { OR 0.98, 95% CI 0.52 to 1.83}.Among the secondary outcomes, urinary hCG did not increase ovulation rate ( OR 0.95, 95% CI 0.49 to 1.83), clinical pregnancy rate (OR 1.02, 95% CI 0.56 to 1.88), multiple pregnancy rate (OR 0.47, 95% CI 0.05 to 4.59), miscarriage rate( OR 1.18, 95% CI 0.18 to 7.66) and preterm delivery (OR 0.12,95% CI 0.00 to 6.29) compared to no treatment. Trials evaluating other ovulation triggers were not identified.

There is inadequate evidence to recommend or refute the use of urinary hCG, as an ovulation trigger, in anovulatory women being treated with clomiphene citrate. We did not find trials evaluating the use of ovulation triggers in anovulatory women, being treated with other ovulation inducing agents.