Moreover, after in vitro BPA treatment, decreased aromatase expression and estradiol synthesis in granulosa cells were observed only in PCOS patients [97], which is in line with observations in women undergoing in vitro fertilization (IVF) treatment, where an inverse association between urinary BPA concentrations and oocytes maturation, number of oocytes retrieved and peak estradiol levels was reported [105]. This evidence concerns the gene CYP19A1 and polycystic ovary syndrome.