A combination of serum AMH and testosterone identifies the diagnosis of PCOS using the Rotterdam criteria with an area under the ROC of 0.79 (95% CI 0.69–0.86), and of the diagnosis of PCOS by the new international criteria with an area under the ROC of 0.77 (95% CI 0.67–0.85). This evidence concerns the gene AMH and polycystic ovary syndrome.