Intrauterine smoke exposure: a new risk factor for bronchopulmonary dysplasia?

Objective: To evaluate the role of intrauterine smoke exposure and other variables on the development of bronchopulmonary dysplasia (BPD) in infants with birth weight 7 days (MV>7), patent ductus arteriosus (PDA), intrauterine smoke exposure ≥3 months (ISE), and of parental history of asthma on BPD (oxygen dependency at 28 days with characteristic radiographic abnormalities) occurrence. Results: Including all variables, only GA 7 were significantly associated with BPD. ISE did not contribute significantly to this model (odds ratio [OR] 1.94; 95% confidence interval 0.88-4.26). Excluding iatrogenic variable MV>7, GA<30, RDS, PDA and ISE (OR 2.21; 95% confidence interval 1.03-4.76) were significantly associated with BPD. Analyzing GA as a continuous variable, the OR was 0.63 for each additional week. Conclusions: Prolonged mechanical ventilation, RDS and low gestational age were the major BPD determinants. Intrauterine smoke exposure seems to influence independently BPD development.