Prematurity and maternal bronchial hyperresponsiveness.

Bronchial reactivity was compared among mothers of neonates with unexplained premature delivery and mothers of preterm neonates with known etiology of prematurity as well as mothers who delivered their children at term. Bronchial reactivity was measured by unspecific bronchial provocation testing with histamine. A significantly higher incidence of bronchial hyperreactivity was found among mothers with unexplained prematurity as compared to the control groups. An imbalance in the autonomic nerve system leading to prematurity as well as bronchial hyperresponsiveness is suggested.