In vitro fertilization (IVF) and embryo transfer (ET) is an effective therapy for PCOS patients and results in pregnancy rates that are comparable with those for women with tubal factor infertility. Moreover, because the number of multiple pregnancies can be kept to a minimum by transferring small numbers of embryos, IVF-ET became a reasonable option to PCOS patients who are refractory to conventional infertility modalities or who have coexisting infertility factors.