Prevalence of premature urinary luteinizing hormone surges in women with regular menstrual cycles and its effect on implantation of frozen-thawed embryos

Objective: To determine the frequency and effect of premature luteinizing hormone (LH) surges on pregnancy rates in women with regular menstrual cycles. Design: Retrospective cohort study. Setting: Assisted Reproductive Technology Program at private medical college. Patient(s): Regularly menstruating women undergoing frozen embryo transfer (ET). Intervention(s): Detection of urinary LH surges with an RIA kit during natural-cycle frozen-embryos transfer. Main Outcome Measure(s): Incidence of premature LH surges and pregnancy outcomes. Result(s): Eighty-eight (46.8%) of 188 regularly menstruating women had premature LH surges and 33 (37%) of those 88 had multiple premature LH surges. Pregnancy rates per ET are similar between women with and without premature LH surges. Conclusion(s): A high percentage of normally cycling women demonstrate premature urinary LH surges without an effect on outcome of frozen-thawed ETs.