A 35-year-old woman with polycystic ovarian syndrome (PCOS) and insulin resistance developed severe hirsutism and virilization during pregnancy, which was the product ofin vitrofertilization. Testosterone level was the highest reported in the literature for a woman: 4050 ng/dL (normal 20–86). The ovaries were bilaterally enlarged and cystic without a dominant mass. She was managed conservatively and delivered a healthy female infant. Postpartum, testosterone level returned to normal but the patient remained significantly more hirsute and virilized than before the pregnancy. We review the causes of hyperandrogenism in pregnancy and conclude that a subset of women with PCOS may develop hirsutism and virilization in pregnancy, especially in the context of assisted reproduction techniques.