MATERNAL TOBACCO-SMOKE EXPOSURE AND PERSISTENT PULMONARY-HYPERTENSIONOF THE NEWBORN

We propose that in utero exposure to tobacco smoke products places a n ewborn at risk for persistent pulmonary hypertension of the newborn (P PHN). To test this hypothesis, infants with PPHN were identified. Heal thy newborns of similar ethnicity were identified as a comparison grou p. Cord blood cotinine concentrations and maternal questionnaires were obtained. The number of women exposed to tobacco smoke in each group ascertained by questionnaire was borderline significantly different (3 8.7% vs. 20.5%; p = 0.080). However, more PPHN infants had detectable cotinine in their cord blood (64.5% vs. 28.2%; p = 0.002), and the med ian cotinine concentrations were significantly higher (5.2 ng/ml vs. 2 ng/ml; p = 0.051) than the comparison infants. Among infants delivere d to nonsmoking women, more PPHN infants had detectable cotinine (50% vs. 19%; p = 0.015), and the cotinine concentrations were higher (3.5 ng/ml vs. 1.65 ng/ml; p = 0.022) than the comparison group. We conclud e that active and passive smoking during pregnancy is a risk factor fo r PPHN. Therefore, we recommend that pregnant women cease smoking and avoid environmental tobacco smoke.