Quadruplet pregnancy after single embryo transfer: а case report

The main goal of in vitro fertilization is a clinical singleton pregnancy with the birth of a healthy child. However, many researchers suggest that assisted reproductive technology programs may increase the incidence of monozygotic multiple pregnancies among patients receiving fertility treatment. Risk factors for multiple monozygotic pregnancies include older maternal age, additional embryo manipulation, and prolonged embryo culture to the blastocyst stage. This paper provides a review of publications concerning multiple monochorionic pregnancies after the implementation of assisted reproductive technology programs. The clinical case of infertility treatment in a woman of advanced reproductive age is presented, and a clinical quadruplet pregnancy was documented following a single frozen-thawed embryo transfer. The authors analyzed this case and suggested the reasons for the multiple pregnancy. The outcome is described, and it is concluded that even selective embryo transfer does not completely eliminate the risk of multiple pregnancy. Μonozygotic pregnancies are considered as high-risk pregnancies due to increased incidence of preterm birth, early pregnancy loss, congenital anomalies, and fetal growth restriction. Further research is required to identify the risk factors associated with monozygotic pregnancies in cycles of infertility treatment involving assisted reproductive technologies.