CYP19A1 and hyperinsulinemic hypoglycemia, familial, 4: The two major causes of maternal endogenous gestational hyperandrogenism are luteomas and ovarian cysts called theca-lutein cysts, as well as placental aromatase deficiency, cytochrome P450 oxidoreductase deficiency (a form of congenital adrenal hyperplasia), PCOS patients with insulin resistance, Sertoli Leydig tumors, Krukenberg tumors, Brenner tumors, fibrothecomas, mucinous and serous cystadenocarcinoma, dermoid cysts, and adrenal tumors.