Predictors of response to ovulation induction using letrozole in women with polycystic ovary syndrome

BACKGROUND: This study aimed to evaluate the predictive value of the initial screening characteristics of women with anovulatory polycystic ovary syndrome (PCOS) who did or did not respond to 2.5 mg letrozole (LET). METHODS: The clinical and laboratory characteristics of women with PCOS who underwent LET treatment were evaluated. Women with PCOS were stratified according to their responses to LET (2.5 mg). The potential predictors of their responses to LET were estimated using logistic regression analysis. RESULTS: Our retrospective study included 214 eligible patients with a response to 2.5 mg LET (n = 131) or no response to 2.5 mg LET (n = 83). PCOS patients who responded to 2.5 mg LET showed better outcomes than those who did not (2.5 mg LET) for pregnancy rate, live birth rate, pregnancy rate per patient, and live birth rate per patient. Logistic regression analyses showed that late menarche (odds ratio OR, 1.79 95% confidence intervals (CI), 1.22-2.64, P = 0.003), and increased anti-müllerian hormone (AMH) (OR, 1.12 95% CI, 1.02-1.23, P = 0.02), baseline luteinizing hormone (LH)/ follicle stimulating hormone (FSH) (OR, 3.73 95% CI, 2.12-6.64, P < 0.001), and free androgen index (FAI) (OR, 1.37 95% CI, 1.16-1.64, P < 0.001) were associated with a higher possibility of no response to 2.5 mg LET. CONCLUSIONS: PCOS patients with an increased LH/FSH ratio, AMH, FAI, and late menarche may need an increased dosage of LET for a treatment response, which could be helpful in designing a personalized treatment strategy.