Placental Chronic Histiocytic Intervillositis: Pregnancy Outcomes and Complications, a Systematic Review and...

Chronic histiocytic intervillositis (CHI) is a rare placental inflammatory condition characterized by the infiltration of monocytes into the intervillous space. CHI is associated with serious neonatal complications. In the present systematic review and meta-analysis, we assessed the relationship between CHI and maternal and neonatal outcomes. The meta-analysis involved searching databases such as EMBASE, PubMed, Web of Science, and SCOPUS for studies on idiopathic CHI up to May 1, 2024. Included studies assessed pregnancy outcomes, including gestational age and live birth status, while excluding nonidiopathic cases. The quality of the studies and risk of bias were evaluated using the Newcastle-Ottawa Quality Scale (NOS). Meta-analyses were then conducted to estimate the frequencies of various pregnancy outcomes. Initially, 402 articles were identified, leading to the inclusion of 12 studies that met the criteria for final analysis. The studies encompassed a total of 568 pregnancies, with sample sizes ranging from 16 to 111 participants and mean ages between 29.8 and 34 yr. The meta-analysis revealed pooled frequencies of 40% for intrauterine growth retardation (IUGR), 55% for live births, and 20% for intrauterine fetal death (IUFD). Sensitivity analyses demonstrated no significant differences when the analysis was restricted to low-risk studies. In conclusion, this meta-analysis highlights the significant associations between CHI and adverse pregnancy outcomes, including high rates of intrauterine growth retardation and intrauterine fetal death. These findings underscore the importance of early detection and management of CHI.