The Diagnostic Promise of Serum S100B Protein in Pregnancy‐Related Hypertension: A Narrative Review

ABSTRACT Background Hypertensive disorders of pregnancy (HDP) are a major cause of illness and death for mothers and babies worldwide. Their number is rising due to older maternal age, obesity, and other health problems. Early diagnosis is important. Serum protein S100B, a calcium‐binding protein studied in brain diseases, is now being considered as a possible marker for predicting HDP. Methods This narrative review looked at studies on S100B and HDP. A search was done in PubMed, Scopus, and Web of Science up to April 2025, with extra searches in Google Scholar. Sixty‐nine studies were included. We reviewed data on S100B structure, function, and its role in blood vessel injury, oxidative stress, and inflammation. Results Studies show that S100B levels are higher in women with preeclampsia than in healthy pregnancies. Increased S100B is linked with blood vessel problems, oxidative stress, and damage to the blood–brain barrier. High levels are also related to more severe disease and neurological symptoms. Other studies found that S100B may help predict complications like preterm birth, growth restriction, and poor newborn outcomes. Experimental studies suggest that S100B acts through the RAGE pathway to worsen inflammation and vascular dysfunction. Conclusions S100B protein has strong potential as a simple, non‐invasive biomarker for early detection and risk assessment in HDP. However, larger studies and standardized testing methods are needed before it can be used in clinics. Combining S100B with known markers such as PlGF and sFlt‐1 may improve accuracy in predicting pregnancy complications.