Objective: To elucidate whether early detection of premature luteinizing hormone (LH) release can be useful for prediction and prevention of ovarian hyperstimulation during purified follicle-stimulating hormone (FSH) therapy.
Design: Retrospective and prospective study.
Patients: Infertile women with polycystic ovarian syndrome.
Main outcome measures: Correlation between rate of endogenous LH release and incidence of excessive ovarian enlargement. In the prospective study, LH was measured by fluorometric enzyme immunoassay to obtain real-time concentration. Maximal ovarian diameter by ultrasonography.
Results: The rate of excessive ovarian enlargement (greater than or equal to 60 mm) in cycles that were treated by a daily administration of purified FSH and accompanied by premature LH release was 83.3%. This rate was significantly higher than that in cycles without premature LH release (24.1%, P less than 0.001). Interruption of FSH administration or alternate day FSH administration in cycles with premature LH release reduced the rate of ovarian enlargement to 45.5% (P less than 0.05).
Conclusion: Early detection of premature LH release is useful for prediction of ovarian hyperstimulation. Ovarian hyperstimulation can be reduced by modulating the dose of FSH and the interval of administration in cycles with premature LH release.