Very low-birth-weight-infants conceived by in vitro fertilization are not at higher risk for mortality and morbidity: a population-based study

Objective: To determine whether excess mortality, neonatal morbidity, and congenital malformations occurred in in vitro fertilization (IVF) conceived compared with naturally conceived singleton, twin and triplet very low birth weight (VLBW) infants. Design: Population-based observational study from 1995 through 2002. Setting: Israel National VLBW infant database. Patient(s): A total of 8,181 VLBW infants conceived naturally or by lVF were stratified into groups of singletons and complete sets of twins and triplets. Intervention(s): None. Main Outcome Measure(s): Neonatal mortality and morbidity. Result(s): in the unadjusted analyses, mortality and neonatal morbidity rates were generally similar between the IVF-conceived and the naturally conceived infants stratified by plurality groups. When adjusted for multiple confounding variables, no excess neonatal mortality or morbidity occurred among IVF-conceived infants. The risk for congenital malformations adjusted for ethnicity, maternal age, and parity was also not increased in the IVF-conceived groups. Conclusion(s): In our population. VLBW infants conceived by IVF were not at increased risk for congenital malformations, postnatal morbidity, or mortality when compared with naturally conceived infants.