Comparative Profiling of Salivary Cortisol and Salivary DHEA-S Among Healthy Pregnant and Non-Pregnant Women.

Abstract

During pregnancy, circulatory cortisol levels increase, remaining steady over the second-third trimester. In contrast, profile of salivary cortisol during pregnancy is debatable, more influenced by factors like time of sample collection in the day. Circulatory DHEA-S decrease by at least 50% over the second-third trimester of pregnancy. However, profile of salivary DHEA-S is unclear. Objective was to determine changes in salivary cortisol and DHEA-S in healthy pregnant women, compared to non-pregnant women during late morning-early afternoon sampling to avoid fluctuations associated with other times. Pregnant women in their second-third trimester prospectively (n=500) and non-pregnant women (n=133) were enrolled in study with informed consent. Live birth outcome with no pregnancy complications and≥2.5 Kg infant birth weight were included. Concentrations of salivary cortisol and DHEA-S were determined through ELISA assays. Compared to non-pregnant women, pregnant women demonstrated significant increases in salivary cortisol [median (interquartile range)=4.2 (5.1) nmol/l vs. 17.2 (13.9) nmol/l, p<0.001] and salivary DHEA-S median (interquartile range)=2.7 (2.9) nmol/l vs. 3.8 (3.2) nmol/l, p<0.001). Consistently, quartile scores representing higher levels of salivary cortisol and DHEA-S concentrations demonstrated significant association with pregnancy. Quartile scores representing higher salivary cortisol/DHEA-S ratio demonstrated significant association with pregnancy. Study suggests the indicated time range of saliva sampling might best parallel the established profile of circulatory cortisol in pregnant women. However, unlike cortisol, study indicates that the salivary DHEA-S profile is distinct from the well-known profile of circulatory DHEA-S during pregnancy. A combinatorial approach involving both salivary and circulatory compartments could provide comprehensive picture of DHEA-S and hypothalamus-pituitary-adrenal axis during pregnancy.