The prevalence and influence of luteinizing hormone surges in stimulated cycles combined with intrauterine insemination during a prospective cohort study

Objective: To reveal the prevalence of premature LH surges in an IUI prog ram. Furthermore, to investigate whether these LH surges influence treatment outcome and whether the prevalence of LH surges differs between cycles stimulated with clomiphene citrate (CC) and cycles stimulated, with recombinant follicle- stimulating hormone (rFSH).Design: Prospective cohort study.Setting: Subfertility patients in a tertiary institutional hospital.Patient(s): A total of 66 subfertile couples undergoing ovarian hyperstimulation combined with IUIIntervention(S): The women were randomized through a central blocked computer system, either to receive CC (33 couples) or rFSH (33 couples), both combined with IUI. Blood for LH detemination was drawn on the day of human chorionic gonadotropin administration.Main Outcome Measure(S): LH surges as well as pregnancy rates.Result(s): In a total of 153 cycles, LH was measured. In 36% of these cycles, LH surges were detected. The results showed that in 42% of the rFSH-stimulated cycles an LH surge was detected, compared with 30% in the cycles with CC (odds ratio 1.7, 95% confidence interval 0.9 to 3.3). There was, a nonsignificant trend showing 4 4 , higher pregnancy rates in cycles without an LH surge (odds ratio 27, 95% confidence interval 0.6 to 13).Conclusion(s): Premature LH surges occur, frequently, and they might:influence treatment outcome negatively. Strategies to improve treatment outcome might focus on preventing premature LH surges.