Establishment and validation of a score to predict ovarian response to stimulation in IVF

This study aimed to integrate clinical and biological parameters in a score able to predict ovarian response to stimulation for IVF in gonadotrophin-releasing hormone (GnRH) antagonist protocols. A progressive discriminant analysis to establish a score including the main clinical and biological parameters predicting ovarian response was performed by retrospectively analysing data from the first ovarian stimulation cycle of 494 patients. The score was validated in a prospectively enrolled, independent set of 257 patients undergoing their first ovarian stimulation cycle. All ovarian stimulations were performed using a combination of GnRH antagonist and recombinant FSH. Ovarian response was assessed through ovarian sensitivity index (OSI). Parameters from the patients' database were classified according to correlation with OSI: the progressive discriminant analysis resulted in the following calculation: score = 0.192 - (0.004 × FSH (IU/l)) + (0.012 × LH:FSH ratio) + (0.002 × AMH (ng/ml)) - (0.002 × BMI (kg/m²)) + (0.001 × AFC) - (0.002 × age (years)). This score was significantly correlated with OSI in the retrospective (r = 0.599; P < 0.0001) and prospective (r = 0.584; P < 0.0001) studies. In conclusion, the score including clinical and biological parameters could explain 60% of the variance in ovarian response to stimulation.