Persistent pulmonary hypertension: assessment of perinatal risk factors.

Persistent pulmonary hypertension of the neonate, a disease of unknown etiology, is associated with a mortality rate as high as 50%. We conducted a retrospective study (1979-1983) to identify antenatal events that may be associated with this disease. Thirty-seven mothers of neonates with this disorder were compared with 150 randomly selected control patients. Logistic regression analysis revealed that meconium, maternal fever (caused by urinary tract infection, upper respiratory infection, chorioamnionitis, and unknown causes), maternal anemia (caused by abruptio placentae, placenta previa, and unknown causes), and maternal pulmonary disease (caused by asthma and/or pneumonia) were associated with persistent pulmonary hypertension of the neonate. The computed odds ratios for the variables associated with this disease were increased significantly above the controls. In addition, cesarean section, nonvertex presentation, fetal distress, and vaginal bleeding were found to be significant on univariate analyses. The cesarean section rate in the study group was 59%, with the primary indications of fetal distress and/or third-trimester bleeding in 77.3% of instances. These data suggest that antenatal risk factors and the computed odds ratio may help identify pregnancies likely to produce infants at high risk for persistent pulmonary hypertension of the neonate.