Neonatal mortality and morbidity in preterm infants born from assisted reproductive technologies

Abstract

Aim: Premature birth is frequent in infants conceived with assisted reproductive technologies (ART). We sought to determine whether neonatal outcome in ART preterm infants differs from that of spontaneously conceived (SC) preterm infants.

Methods: Data were prospectively collected in infants born ≤ 32 weeks after ART or SC. We calculated a composite index of severe morbidity (based on occurrences of severe necrotizing enterocolitis, severe intraventricular haemorrhage, periventricular leukomalacia or bronchopulmonary dysplasia). Survival rate without severe morbidity was compared between the two groups.

Results: Six hundred and twelve preterm infants were hospitalized in our tertiary care centre: 81 in ART group and 521 in SC group. In the ART group, twin pregnancy (69.1% vs. 15.9%, p < 0.001) and inborn delivery (98.8% vs. 90.0%, p < 0.01) were more frequent. Gestational age (29 vs. 28 weeks, p < 0.05) and birth weight (1100 vs. 1020 g, p < 0.001) were also higher. Survival without severe morbidity was significantly higher in ART infants (76.5% vs. 55.2%, p < 0.001), with the difference mainly observed in infants born ≤ 28 weeks (22.9% vs. 55.7%, p < 0.001).

Conclusion: Assisted reproductive technologies was not associated with adverse neonatal outcome. Differences in pregnancy and neonatal characteristics probably explain the increased survival without severe morbidity in ART infants.