Do Premature Female Infants Really Do Better Than Their Male Counterparts?

ABSTRACT

We compared survival and outcomes in process of care in female versus male infants born ≤32 weeks gestational age (GA). Data were obtained from the Alere database for infants born ≤32 weeks GA. Females were compared with males for demographics, complications, and care processes. Univariate and multivariate analysis was conducted using chi-square analysis, analysis of variance, or logistic regression. Of the infants included, 6086 female and 6721 males were included. Mean GA did not differ, males were born larger than females, and females were more likely to be born SGA. Males received more surfactant, developed more CLD, received more steroids, and more often required oxygen at discharge. Females were more likely to develop a patent ductus arteriosus. After controlling for body weight, GA, and small-for-GA status, females were more likely to survive (95.4% versus 93.6%, odds ratio 1.63, p < 0.01). Male sex did not play a role in other processes of care except for weaning to a crib. Male infants born ≤32 weeks GA have a decreased rate of survival and an increased rate of respiratory morbidity in spite of higher birth weight distributions. Sex did not play a role in other processes of care.

KEYWORDS

Male - female - survival - outcome - low birth weight - prematurity

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