Perinatal Outcomes in Pregnancies Immediately following Stillbirth: A Multicenter, Prospective, Observational Study

Objective This study aimed to evaluate the outcomes of pregnancies immediately following stillbirth in relation to treatments prescribed. Study Design A prospective, observational study was conducted in patients with a history of stillbirth (≥22 weeks) between 2014 and 2022 across four Italian University Hospitals. Outcomes were stratified based on the cause of previous fetal death (classified according to ReCoDe classification) and treatment (low dose aspirin [LDA], low molecular weight heparin [LMWH], both, progesterone, or other drugs). The main outcome was adverse neonatal outcome, including perinatal death, stillbirth recurrence, intrauterine growth restriction, early preterm birth, Apgar < 7 at 5 minutes, and need for neonatal resuscitation. The secondary outcome was adverse maternal outcome, including postpartum hemorrhage, emergency cesarean delivery, and operative vaginal delivery. Results Among 308 subsequent pregnancies, 46 (14.94%) had an adverse neonatal outcome, including 4 stillbirths. A total of 76 pregnancies (24.68%) experienced adverse maternal outcome, and 19 pregnancies (6.17%) had both. In individuals with previous placental vascular disorders (PVDs), adverse neonatal outcomes were reduced by 75% when treated with LDA þ LMWH (odds ratio [OR]: 0.25; 95% confidence interval [CI]: 0.06-1.03; p ¼ 0.049). However, adverse maternal outcome was significantly higher in individuals who received LDA þ LMWH without specific indications (OR: 3.07; 95% CI: 1.07-8.78; p ¼ 0.036). Conclusion LDA and LMWH should be prescribed only for previous PVDs to improve adverse neonatal outcome and avoid unnecessary maternal risk.