Cycle fecundity in controlled ovarian hyperstimulation and intrauterine insemination. Influence of the number of mature follicles at hCG administration.

Objective: To determine if cycle fecundity in controlled ovarian hyperstimulation (COH) with intrauterine insemination (IUI) cycles is influenced by the number of mature follicles at the time of hCG administration.

Study Design: Retrospective data analysis of 75 infertility patients undergoing 164 consecutive COH/IUI cycles with FSH and/or hMG in a university-affiliated private infertility center. Cycles were compared for number of mature follicles (> or = 15 mm) and peak serum estradiol levels, total number of ampules and days of gonadotropin use, and clinical pregnancy rate.

Results: There was a statistically significant increase in cycle fecundity when three to four mature follicles were stimulated. Peak estradiol levels were significantly different in the groups, as predicted from the number of follicles. The groups were not statistically different in age or etiology of infertility. Group A (1-2 mature follicles) required significantly more FSH/hMG than group B (3-4 follicles) or group C (> or = 5 follicles).

Conclusion: In COH/IUI cycles, three to four mature follicles yield improved cycle fecundity as compared to that in cycles with a smaller or larger number of follicles. These findings may help identify patients who will be more successful in conceiving with COH/IUI versus those who should be counseled to use other assisted reproductive technologies.