Perinatal outcomes in normotensive versus hypertensive HELLP syndrome

To compare maternal and neonatal outcomes between women with hemolysis, elevated liver enzymes, and low platelets (HELLP) syndrome with and without associated hypertension.

This was a retrospective cohort study at a tertiary university-affiliated medical center including all singleton HELLP cases >24 weeks gestation (January 2011-March 2023). Cases were categorized as normotensive or hypertensive HELLP and compared for demographics, presentation, laboratory findings, and outcomes.

Among 157 282 deliveries, 108 met the full criteria for HELLP syndrome: a total of 74 (68.5%) were hypertensive and 34 (31.5%) were normotensive. Normotensive HELLP cases were diagnosed at a significantly later gestational age (37.5 ± 3.0 vs 34.5 ± 4.4 weeks, P < 0.001). Proteinuria was less common in normotensive cases (58.8% vs 87.8%, P < 0.001). Laboratory parameters did not differ significantly between the groups. Neonates in the normotensive group had significantly higher mean birth weight (2574.6 ± 746.2 vs 1947 ± 816.6 g, P < 0.001), fewer neonatal intensive care admissions (29.4% vs 56.8%, P = 0.008), and lower rates of respiratory distress syndrome (2.9% vs 24.3%, P = 0.007). Maternal complications related to HELLP syndrome did not differ significantly between groups.

Normotensive HELLP was diagnosed at a later gestational age and was associated with more favorable neonatal outcomes, yet comparable maternal outcomes. Despite the absence of hypertension, maternal complications were not reduced.