Early-onset preeclampsia: gestational age threshold of potential benefits

Delivery timing in pregnancies complicated by early-onset preeclampsia with severe features (sPEC) is individualized, aiming to prolong gestation for fetal benefit while minimizing maternal risk.

To determine whether expectant management (EM), compared to expedited delivery (ED), improves neonatal outcomes in pregnancies complicated by sPEC.

This retrospective cohort study evaluated pregnancies complicated by sPEC within a large New York health system from 2019 to 2023. Pregnancies requiring immediate delivery (<24 h after diagnosis or without betamethasone administration) were excluded. Patients were classified as ED if delivery occurred within 24-72 h after diagnosis, and EM if delivery occurred after 72 h. The primary outcome was severe neonatal morbidity (SNM), a composite of diagnoses and procedures indicative of life-threatening complications. Secondary outcomes included neonatal death, respiratory distress syndrome (RDS), bronchopulmonary dysplasia (BPD), intraventricular hemorrhage (IVH), sepsis, and NICU discharge metrics. Outcomes were analyzed by gestational age at diagnosis: <28 weeks and 28-33 weeks.

Of 225 pregnancies included, 36 (16.0%) were diagnosed with sPEC < 28 weeks and 189 (84.0%) between 28-33 weeks. Rates of SNM were similar between ED and EM at both gestational age groups (<28 weeks: 92.3% vs. 91.3%; 28-33 weeks: 82.6% vs. 78.3%). Neonatal death was more common in the < 28-week ED group (38.5% vs. 4.3%). Among pregnancies diagnosed at 28-33 weeks, NICU length of stay was shorter in the EM group (21.1 vs. 28.4 days, p = 0.03), while postmenstrual age at discharge was similar (35.4 vs. 35.3 weeks, p = 0.82).

For sPEC diagnosed between 28-33 weeks, EM did not significantly reduce SNM but was associated with shorter NICU stays. Among pregnancies diagnosed before 28 weeks, neonatal mortality was higher in the ED group, supporting EM when maternal condition permits.