The association of in vitro fertilization and perinatal morbidity.

In recent years, there has been increasing concern regarding the safety of in vitro fertilization (IVF) because of the potential health impact on these infants. Multiple pregnancy contributes the vast majority of morbidity associated with IVF and, initially, many thought that adverse outcomes after IVF were solely attributable to the high incidence of twin pregnancies. More recently, multiple studies have suggested that IVF singleton pregnancies may be at increased risk for preterm birth, low birth weight, congenital anomalies, perinatal mortality, and several other pregnancy-related complications compared with unassisted singleton pregnancies. We have focused this review on the increased risk of adverse outcomes in IVF singleton conceptions compared with that of unassisted conceptions. The available evidence evaluating the association between IVF and low birth weight, preterm delivery, placental abruption, preeclampsia, congenital anomalies, and perinatal mortality in singleton pregnancies is summarized. In addition, data reporting an increased risk of congenital and chromosomal anomalies after IVF are presented.