Antepartum Serum Lactate Dehydrogenase and Adverse Obstetric Outcomes in Preeclampsia: A Systematic Review of Prognostic Evidence From Low- and Middle-Income Countries.

This systematic review evaluated the association between antepartum serum lactate dehydrogenase (LDH) levels and adverse maternal and perinatal outcomes in preeclamptic pregnancies in low- and middle-income countries (LMICs). A comprehensive search of PubMed, Embase, and Scopus identified 19 observational studies published between 2000 and 2025, comprising 5,039 pregnant women, including 3,782 preeclampsia diagnoses. Most studies were conducted in South Asia and the Middle East. Although LDH thresholds varied, a consistent trend was observed: higher LDH levels were associated with increased risk of maternal complications such as HELLP syndrome, disseminated intravascular coagulation, acute renal failure, and ICU admission. Perinatal complications, including stillbirth, intrauterine growth restriction, low Apgar scores, and neonatal intensive care unit (NICU) admission, were also more common at LDH levels >800 IU/L. For example, stillbirth occurred in up to 77.7% of cases in the highest LDH group compared to <3% in the lowest. Due to heterogeneity in cut-offs and outcome definitions, meta-analysis was not performed. Overall, elevated antepartum serum LDH appears to be a strong prognostic marker for severe outcomes in preeclamptic pregnancies and may aid clinical triage in LMICs. Further prospective studies are needed to establish standardized thresholds and validate their predictive utility.