Predicting ongoing pregnancy following ovulation induction with recombinant FSH in women with polycystic ovary syndrome

BACKGROUND: Ovulation induction with recombinant FSH (rFSH) is common in women with polycystic ovary syndrome (PCOS) not responding to clomiphene citrate treatment, despite the associated risk of multiple pregnancies. We analysed clinical, ultrasonographic and endocrine parameters during initial screening of women with clomiphene citrate-resistant PCOS as predictors of ongoing pregnancy within 12 months of treatment following ovulation induction with rFSH. METHODS: Eighty-five women were allocated to receive rFSH as part of a multi-centre clinical trial. rFSH was administered in a chronic low-dose step-up protocol. The primary end-point was an ongoing pregnancy within 12 months. A logistic model was built using clinical, ultrasonographic and endocrine parameters to predict the response to rFSH treatment, adjusted for the number of cycles performed. RESULTS: In total, 85 women underwent 272 treatment cycles with rFSH, of which 57 women (67%) achieved an ongoing pregnancy. Oligomenorrhoea, shorter duration of infertility and a lower free androgen index (FAI) were associated with higher chances of an ongoing pregnancy, resulting in a predictive model with a modest discriminative power (area under the curve 0.72, 95% confidence interval 0.64-0.79) that allowed us to distinguish between women with a probability of < 5% of attaining an ongoing pregnancy and women with a probability of > 25% of doing so. CONCLUSION: A model consisting of oligo/amenorrhoea, duration of infertility and FAI level allowed a distinction to be made between women with a poor chance and women with a good chance of achieving an ongoing pregnancy.