The Role of lncRNAs in Complicated Pregnancy: A Systematic Review

Background/Objectives: Long non-coding RNAs (lncRNAs) play a crucial role in trophoblast invasion, immune tolerance, and placental angiogenesis. To delineate their diagnostic and pathological significance, we critically evaluated the evidence for correlations between circulating or placental lncRNA profiles with pregnancy complications. Methods: Five databases were searched from inception through September 2024. We included only the studies that assessed the expression of the lncRNA-complicated pregnancies versus a control group. Results: Three single-center case-control studies fulfilled the inclusion criteria. Eight serum lncRNAs that present <20 weeks of gestation were elevated in subsequent pregnancy-induced hypertension or preeclampsia. The three lncRNAs in intrahepatic cholestasis of pregnancy were consistently decreased with a negative correlation with bile acids. Gestational diabetes was characterized by the elevation of MALAT1. Conclusions: Different lncRNAs showed a potential for use as non-invasive markers as well as for risk stratification for pregnancy-induced hypertension or preeclampsia, metabolic, and hepatobiliary pregnancy complications. There is a need for large-scale, multi-ethnic, prospective cohorts to include lncRNA as screening or therapeutic targeting in obstetric practice.