Maternal hypertension and neonatal outcome among small for gestational age infants

Objective: To determine whether maternal hypertension might improve perinatal outcome among small for gestational age (SGA) infants (< 10th percentile). Methods: Our prospective cohort comprised 17 Canadian neonatal intensive care units (NICUs) and 3,244 SGA singletons. Multivariable regression was used to analyze the relation between maternal hypertension and each of the following: SNAP-II (Score of Neonatal Acute Physiology; ordinal regression) and neonatal survival and survival without severe intraventricular hemorrhage (logistic regression), adjusting for potential confounders. Results: There were 698 (21.5%) neonates born to hypertensive mothers. Inversely associated with lower SNAP-II scores (healthier infant) were antenatal steroids (complete course: odds ratio [OR] 0.67, 95% confidence interval [CI] 0.54-0.83; incomplete: OR 0.71, 95% CI 0.56-0.88), lower gestational age (< 27 weeks: OR 0.06, 95% CI 0.05-0.08; 27-28 weeks: OR 0.11, 95% CI 0.07-0.17; 29-32 weeks: OR 0.28, 95% CI 0.23-0.35), 5-minute Apgar < 7 (OR 0.30, 95% CI 0.25-0.36), male gender (OR 0.80, 95% CI 0.70-0.92), and anomalies (OR 0.49, 95% CI 0.41-0.58). Maternal hypertension was associated with lower SNAP-II (healthier infant) (7.54 +/- 11.16 [hypertensive] versus 7.21 +/- 11.85 [normotensive]) on multivariable regression analysis (adjusted OR 1.25, 95% CI 1.05-1.49), as well as higher neonatal survival (93.0% versus 91.2%, and adjusted OR 1.9, 95% CI 1.2-3.0), but not survival without severe intraventricular hemorrhage (91.4% versus 87.0%, and adjuted OR 1.4, 95% CI 1.0-2.0), respectively. Conclusion: Among SGA neonates in NICU, maternal hypertension is associated with improved admission neonatal physiology and survival.