Predictive Value of Elevated LH/FSH Ratio for Ovulation Induction in Patients with Polycystic Ovary Syndrome.

ABSTRACT

OBJECTIVE: To assess the value of an elevated luteinizing hormone (LH)-to-follicle-stimulating hormone (FSH) ratio in predicting development of a dominant follicle when ovulation induction is implemented with clomiphene citrate (CC) or letrozole in women with polycystic ovary syndrome (PCOS). STUDY DESIGN: Retrospective review of 312 monitored cycles between 2007 and 2012. All patients met the diagnostic criteria set by the 2006 Androgen Excess-PCOS Society and had baseline LH and FSH levels drawn. Only ovulation induction with CC or letrozole was included. Primary outcome was development of a dominant follicle of ≥ 18 mm. RESULTS: The development of a dominant follicle was significantly associated with clinical pregnancy. The development of a dominant follicle was also higher in the letrozole group as compared to the CC group (87.6% [155/177] vs. 62.2% [84/135], p < 0.001). Furthermore, treatment with letrozole significantly increased the odds of forming a dominant follicle when LH/FSH ratio was ≥ 1 (odds ratio [OR] 7.69, CI 3.69-16.02). When LH/ FSH ratio was < 1, letrozole had no significant effect on dominant follicle development (OR of 3.63, CI 0.92-14.25). CONCLUSION: LH/FSH ratio ≥ 1 could be useful as a predictive tool to identify which subgroup of PCOS patients may be more successful in forming a dominant follicle when using letrozole as compared to CC.