When both GSTs are deleted, the risk of developing female infertility is significant, independently of the CYP19A1 genotype; when all the presumed high-risk genotypes are present, we found a significant association with female infertility risk (OR 47,914; 95% CI (14,051–163,393; p < 0.001). The gene discussed is CYP19A1; the disease is female infertility.