Objectives: To assess the relation between cigarette smoking during pregnancy and neonatal respiratory distress syndrome (RDS) in very preterm birth, and to analyse the differential effect of antenatal steroids on RDS among smokers and non-smokers.Design: A population based cohort study (the French Epipage study).Setting: Regionally defined births in France.Methods: A total of 858 very preterm liveborn singletons (27-32 completed weeks of gestation) of the French Epipage study were included in this analysis. The odds ratio for RDS in relation to smoking in pregnancy was estimated using a logistic regression to control for gestational age. The odds ratio for RDS in relation to antenatal steroids was estimated taking into account an interaction between antenatal steroids and cigarette smoking, using multiple logistic regression to control for gestational age, birthweight ratio, main causes of preterm birth, mode of delivery, and sex.Results: The odds ratio for RDS in relation to smoking in pregnancy adjusted for gestational age (aOR) was 0.59 (95% confidence interval (CI) 0.44 to 0.79). The aOR for RDS in relation to antenatal steroids was 0.31 (95% CI 0.19 to 0.49) in babies born to non-smokers and 0.63 (95% CI 0.38 to 1.05) in those born to smokers; the difference was significant (p = 0.04).Conclusions: Cigarette smoking during pregnancy is associated with a decrease in the risk of RDS in very preterm babies. Although antenatal steroids reduce the risk of RDS in babies born to both smokers and non-smokers, the reduction is smaller in those born to smokers.

Between 1990 and 1994, 105 children were admitted for whooping cough to one of the 22 intensive care units belonging to the Pediatric Intensive Care Unit, French Language Group. On admission to ICU, 78 children were less than 3 months old, 9 of which were less than 30 days old, 24 children were aged between 3 and 6 months, 2 children between 6 and 12 months and only one child was older than 12 months. 98 % of these children suffered from paroxysmal cough, 50 % from bradycardia, 21 % from apnea and 9 % from life-threatening whooping cough as identified by Huault in 1983. Among the complications, 2 cases of pneumothorax, 17 cases of atelectasis, 11 cases of bronchopneumonia (gram negative organism in 8 cases), 2 cases of septicemia and 6 cases of seizures were worthy of note. The mean leucocyte and lymphocyte maximum values were statistically different in children suffering from life-threatening whooping cough as compared to children suffering from the other forms of whooping cough : 99 100/mm(3) in the first group compared to 28 000/mm(3) and 41 200/mm(3) in the first group compared to 19 410/mm(3) in the second group respectively. A significant difference was also recorded in these 2 groups with regard to the minimum blood sodium value which was 123 and 136 mmol/l respectively. 34 children required mechanical ventilation for a mean duration of 8,3 days (1-21 days). 7 children (6,6 %) died, all of them belonging to the life-threatening group.