Does anovulation induced by oral contraceptives favor pregnancy during thefollowing two menstrual cycles?

Objective: To compare IVF and pregnancy outcomes before and after anovulati on induced by oral contraceptives. Design: Observational clinical study. Setting: Infertility clinic. Patient(s): Forty women with two intact ovaries (32 of 40 couples with male factor infertility and 8 with unknown causes of infertility) underwent 190 IVF treatment cycles (55 natural cycles and 135 clomiphene citrate-stimula ted cycles). Intervention(s): If the women failed to conceive after 2-4 IVF treatment cy cles, oral contraceptives were used to induce anovulation for 1 month befor e IVF was performed in two consecutive cycles. Main Outcome Measure(s): Rates of oocyte retrieval, fertilization, cleavage , preembryo formation, pregnancy, and implantation were compared before and after a period of anovulation, Result(s): The pregnancy rate per cycle of the first and second cycle combi ned (23%) and that of the second cycle alone (30%) after a period of anovul ation were significantly higher than that observed before a period of anovu lation (9%). Conclusion(s): Anovulation induced by oral contraceptives, showing bilatera l ovarian quiescence, enhances pregnancy rates in the following two menstru al cycles of IVF treatment.