Incidence of histologic chorioamnionitis following fetal surgery and its association with maternal and neonatal outcomes

Abstract

Objective: Chorioamnionitis is a recognized complication of intra-amniotic interventions. The implications of histologic chorioamnionitis (HCA) in fetal surgery is poorly understood. We aimed to evaluate the incidence of acute HCA following fetoscopic repair of fetal myelomeningocele (fMMC) and its associations with baseline clinical variables as well as maternal, perinatal, and neonatal outcomes. Methods: A retrospective review at our single fetal therapy center was performed of patients who underwent fMMC repair between April 2018 and October 2023. Acute HCA was based on final placental pathology report. Baseline demographics, relevant clinical characteristics, operative details, and outcomes were compared among those with and without acute HCA. Results: Fifteen patients underwent fMMC repair; one was lost to follow-up (n = 14). Acute HCA was diagnosed in 8/14 (57%) patients. Only one met criteria for clinical chorioamnionitis. A majority of patients with acute HCA (6/8; 75%) had preterm premature rupture of membranes (PPROM) at an earlier median gestational age (GA) 28 weeks vs. 35.9 weeks, (p = 0.02). Delivery also occurred at an earlier median GA in those with acute HCA, 31.1 weeks vs. 36.9 weeks. (p = 0.01). Birth weights were lower (1470 g vs. 2900 g, p = 0.007) and NICU stay was longer (42 days vs. 9 days, p = 0.02) in patients with acute HCA. When adjusting for PPROM, HCA also independently correlated with longer NICU length of stay. Neonates with acute HCA stayed more than one month longer than those without HCA (34.9 days [95%CI 6.8, 63], p = 0.033). Conclusion: Acute HCA is not an uncommon finding after fetal surgery. More than half of the patients in our population were diagnosed with acute HCA and significant associations were noted with poorer perinatal and neonatal outcomes. Larger multicenter studies are needed to further examine the relationship with HCA and PPROM, and outcomes following fetal surgery.