[en] Purpose: A twin pregnancy was obtained in a patient with polycystic ovary syndrome after the transfer of three in vitro maturation-derived day 3 embryos that has been frozen and thawed. Methods: The patient had received mild hMG stimulation followed by hCG injection. After culture for 24 - 48 h, mature oocytes were fertilized by ICSI. Embryos were cultured until day 3; supernumerary embryos were cryopreserved using a slow protocol. Results: Among 15 nonatretic oocytes, 9 matured, 8 were fertilized. Four embryos were transferred but they did not implant. The subsequent transfer of three frozen - thawed embryos resulted in the delivery of two healthy girls. Conclusions: These results indicate that a pregnancy could be obtained with in vitro maturation-derived day-3 frozen - thawed embryos.