A randomized prospective study comparing pregnancy rates following clomiphene citrate and human menopausal gonadotrophin therapy.

The anti-oestrogenic effect of clomiphene citrate causes an increased rate of associated cervical factor problems. Theoretically, it may also cause an adverse effect on the endometrium. The hostile mucus may be completely or partially corrected by the use of additional oestrogen after stopping clomiphene, or by intrauterine insemination (IUI). The prospective randomized study presented here was designed to determine whether a higher pregnancy rate might be achieved using human menopausal gonadotrophin (HMG) compared to clomiphene citrate. Thirty-seven women treated with clomiphene citrate for 165 cycles were compared to 33 treated with HMG for 179 cycles. A pregnancy was achieved in 81.1% of clomiphene-treated women (18.2%/cycle) versus 72.7% (13.3% per cycle) of HMG-treated women. The abortion rates of 13.3 and 12.5% respectively, were similar. The data suggest no adverse effect of clomiphene compared to HMG as far as pregnancy rates are concerned. IUI seems to be an effective means of treating cervical factor problems induced by clomiphene.