Abstract
Introduction:
Although important new strategies have improved outcomes for very preterm infants, males have greater mortality/morbidity than females. We investigated whether the excess of adverse later effects in males operated through poorer neonatal profile or if there was an intrinsic male effect.
Results:
Male sex was significantly associated with higher birth weight, death or oxygen dependency (72% vs. 61%, boys vs. girls), hospital stay (97 vs. 86 days), pulmonary hemorrhage (15% vs. 10%), postnatal steroids (37% vs. 21%), and major cranial ultrasound abnormality (20% vs. 12%). Differences remained significant after adjusting for birth weight and gestation. At follow-up, disability, cognitive delay, and use of inhalers remained significant after further adjustment.
Discussion:
We conclude that in very preterm infants, male sex is an important risk factor for poor neonatal outcome and poor neurological and respiratory outcome at follow-up. The increased risks at follow-up are not explained by neonatal factors and lend support to the concept of male vulnerability following preterm birth.
Methods:
Data came from the United Kingdom Oscillation Study, with 797 infants (428 boys) born at 23–28 wk gestational age. Thirteen maternal factors, 8 infant factors, 11 acute outcomes, and neurological and respiratory outcomes at follow-up were analyzed. Follow-up outcomes were adjusted for birth and neonatal factors sequentially to explore mechanisms for differences by sex.
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Peacock, J., Marston, L., Marlow, N. et al. Neonatal and infant outcome in boys and girls born very prematurely. Pediatr Res 71, 305–310 (2012). https://doi.org/10.1038/pr.2011.50
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DOI: https://doi.org/10.1038/pr.2011.50
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