Associations Between Maternal Abortion History and Neonatal Outcome among Very Preterm Infants：a multicenter cohort study

Background It is unclear whether there is an association between maternal abortion history and neonatal outcomes of singleton very preterm infants (VPIs). We assess the association between maternal abortion history and neonatal outcome of VPIs in China. Methods All first parity singleton VPIs born at < 32 weeks gestational age (GA) who were admitted to neonatal intensive care units (NICU) participating in the Chinese Neonatal Network (CHNN) from 2019 to 2021 were included in the study. Multivariable logistic regression models were constructed to compare neonatal outcomes among infants with different maternal abortion histories after adjusting for confounders. Results A total of 7256 VPIs were included in this analysis. Overall, 3133 (43.2%) infants had positive maternal abortion history. The incidence of mortality or any major morbidity including respiratory distress syndrome (RDS), patent ductus arteriosus (PDA), intraventricular haemorrhage (IVH), IVH stage 3 or 4, moderate or severe bronchopulmonary dysplasia (BPD), retinopathy of prematurity (ROP), ROP stage 3, 4, or 5 tended to increase significantly with increasing number of maternal abortion histories from non-abortion group to ≥2 abortions group. Multivariable analysis showed that maternal abortion history was significantly associated with higher risks of mortality or any major morbidity (adjusted odds ratio [aOR] 1.15, 95% confidence interval [CI] 1.03–1.29), RDS (aOR 1.22, 95%CI 1.08–1.38), IVH (aOR 1.17, 95% CI 1.05–1.31), and IVH stage 3 or 4 (aOR 1.27, 95% CI 1.01–1.59). Risk increased with the number of abortions. VPIs of mothers with two or more abortions had the highest risk of mortality or any major morbidity (aOR 1.18, 95% CI 1.02–1.36), RDS (aOR 1.35, 95% CI 1.18–1.56), IVH (aOR 1.23, 95% CI 1.07–1.43) and moderate or severe BPD (aOR 1.17, 95% CI 1.01–1.36), compared to the non-abortion group. Conclusions In China, VPIs born to mothers with previous abortion history may have a greater risk of adverse outcomes. Based on the potential impact of maternal abortion history on newborns, it is necessary to provide additional information on related risks during antenatal counseling for these mothers.