EPIDEMIOLOGIC ASSOCIATION BETWEEN MATERNAL SMOKING DURING PREGNANCY AND INTRACRANIAL HEMORRHAGE IN PRETERM INFANTS

The objective of this study was to evaluate the effect of maternal smo king during pregnancy on the risk of intracranial hemorrhage in preter m infants (born at 24 to 33 weeks of gestation). We conducted a case-c ontrol study of 96 preterm infants with intracranial hemorrhage and 96 gestational age-matched control subjects with negative cranial ultras onographic findings. In conditional multiple logistic regression model s, heavy maternal smoking (> 10 cigarettes per day) during the latter half of pregnancy was associated with an increased risk of mild (grade I or II) intracranial hemorrhage (odds ratio = 5.96, 95% confidence i nterval 1.72 to 20.76; p = 0.005), After adjustment for the confoundin g effect of birth weight and respiratory distress syndrome, the risk o f any intracranial hemorrhage (grade I to IV) was three times higher ( adjusted odds ratio = 3.63, 95% confidence interval 1.37 to 9.63; p = 0.009) in infants of heavy smokers (> 10 cigarettes per day) than in c ontrol subjects. The results of this study indicate that cigarette smo king during the latter half of pregnancy increases the risk of intracr anial hemorrhage in preterm infants, The deleterious effect of smoking was greater for mild hemorrhages (grade I or II) and was confined to infants of heavy smokers.