Do premature female infants really do better than their male counterparts?

Area of Science:

• Neonatology
• Perinatal Medicine
• Pediatric Research

Background:

• Premature infants born at less than 32 weeks gestational age (GA) face significant survival and morbidity challenges.
• Understanding sex-based differences in outcomes for extremely preterm infants is crucial for optimizing care.

Purpose of the Study:

• To compare survival rates and care processes between female and male infants born at or before 32 weeks GA.
• To identify specific factors influencing outcomes in this vulnerable population.

Main Methods:

• Retrospective analysis of the Alere database for infants born ≤32 weeks GA.
• Demographic, complication, and care process data were compared between sexes using univariate and multivariate statistical analyses (chi-square, ANOVA, logistic regression).

Main Results:

• No significant difference in mean gestational age (GA) between sexes.
• Males were larger at birth, while females had a higher incidence of being small-for-GA (SGA).
• Males received more surfactant and steroids, developed more chronic lung disease (CLD), and required more oxygen at discharge. Females had a higher incidence of patent ductus arteriosus.
• After adjusting for birth weight, GA, and SGA status, females demonstrated significantly higher survival rates (95.4% vs. 93.6%, OR 1.63, P < 0.01).

Conclusions:

• Male infants born extremely preterm exhibit decreased survival rates and increased respiratory morbidity despite higher birth weights.
• Female infants born extremely preterm have a higher likelihood of survival, independent of birth weight, GA, and SGA status.
• Sex did not significantly influence most other care processes, except for the method of weaning to a crib.