Sex differences in intraventricular hemorrhage rates among very low birth weight newborns.
BACKGROUND
The influence of male or female sex on newborn outcomes has been recognized for >30 years. Several studies have observed higher mortality and morbidity in males than in females. It is not clear how this sex difference is sustained in postnatal complications such as intraventricular hemorrhage (IVH), especially in very low birth weight (VLBW) newborns.


OBJECTIVE
This study examined possible sex-related differences in IVH rates among VLBW neonates.


METHODS
In a retrospective observational study conducted in Hospital Privado, Córdoba, Argentina, data from 332 consecutive VLBW newborns in a 12-year period were reviewed. Maternal factors, labor and delivery characteristics, and neonatal parameters, including the results of cranial ultrasound examination to detect IVH, were compared for males and females. Bivariate and multivariate logistic regression analyses were performed.


RESULTS
A total of 322 VLBW newborns were included, 168 males and 154 females. Compared with female neonates, male neonates had a higher risk of overall IVH (26.8% vs 9.7%; odds ratio [OR] = 3.4 [95% CI, 1.8-6.4]; P < 0.001) and for grades III or IV on the Papile scale (16.1% vs 1.9%; OR = 9.6 [95% CI, 2.9-32.5]; P < 0.001). In the multivariate logistic regression model, male sex sustained the association with a greater risk of IVH (OR = 6.8 [95% CI, 3.8-12.0]).


CONCLUSIONS
IVH was significantly associated with male sex in these VLBW newborns. Because other factors affect these differences, further research is required.
Cuestas
Eduardo
E
Department of Pediatrics and Neonatology, Hospital Privado, School of Medicine, Catholic University of Córdoba, Córdoba, Argentina. ecuestas@hospitalprivadosa.com.ar
Bas
Jose
J
Pautasso
Josefina
J
D001118:Argentina / Q000453:epidemiology; D002543:Cerebral Hemorrhage / Q000000981:diagnostic imaging / Q000453:epidemiology*; D002552:Cerebral Ventricles / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D015994:Incidence; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000000981:diagnostic imaging / Q000453:epidemiology*; D019102:Infant, Very Low Birth Weight; D008297:Male; D016017:Odds Ratio; D012189:Retrospective Studies; D012307:Risk Factors; D017678:Sex Distribution; D014463:Ultrasonography