Hair Cortisol Concentrations as a Biological Marker of Maternal Prenatal Stress: A Systematic Review

Recently, biological markers of maternal prenatal stress, hair cortisol, along with saliva, blood, and urine cortisol, have received attention. However, it is necessary to validate measuring hair cortisol concentrations (HCC) as a biomarker of perceived stress among healthy and high-risk pregnant women. This study aimed to confirm the correlation between HCC and the perceived stress of pregnant women over 18 years of age. In this systematic review, we used various search engines to extract relevant articles using specific keywords related to pregnancy, hair cortisol, and psychological stress. Four out of 3639 studies met the inclusion criteria. We conducted a quality assessment with the help of three independent reviewers using the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement. The correlation between HCC and perceived stress was confirmed in one study. There was only one study on hair washing, shampoo, conditioner, and hair structure that could affect hair samples. In four studies, hair samples differed in length, methods of storage, and laboratory analysis. The review was limited to confirming the relationship between HCC and perceived stress in pregnant women based on the current evidence. Studies on hair cortisol need regulated and standardized methods for collection, storage, and analysis of hair samples.