Dehydroepiandrosterone sulfate (DHEA-S) is an endogenous steroid hormone produced primarily by the adrenal cortex in response to adrenocorticotrophin (ACTH). It belongs to the chemical class of adrenal hormones and is a sulfated metabolite of dehydroepiandrosterone (DHEA). DHEA-S circulates in the blood, mostly bound to albumin, and is a precursor to sex steroids. Researchers have found that DHEA-S plays a significant role in various physiological processes, including androgen and estrogen formation, and acts as a metabolic intermediate in ovarian follicular steroidogenesis. It is involved in the regulation of calcium channels, which are crucial for oocyte activation and maturation, making it relevant in reproductive health and assisted reproductive technologies. DHEA-S is also implicated in skeletal maturation during puberty and has been studied in relation to stress, central nervous system function, insulin sensitivity, immunological function, and cardiovascular health. The mechanism of action of DHEA-S involves its conversion to active androgens and estrogens in peripheral tissues, influencing various biological pathways. It is known to regulate calcium oscillations in oocytes, which are essential for fertilization. Pharmacokinetically, DHEA-S has a slower metabolic clearance rate compared to DHEA, with researchers noting that it is preferred for estimating chronic adaptations in response to exercise. Clinical use of DHEA-S is still under investigation, with its supplementation being explored for enhancing ovarian reserve and as a non-invasive method for oocyte activation. Regulatory standing varies by region, with different legal classifications in place.