Major Approaches of Molecular and Physiopathological Mechanisms for Hormonal Treatment of Melasma: A Systematic Review

The systematic review examined the hormonal treatment of melasma, focusing on the roles of estrogens and progesterone. It found that estrogens, particularly 17-β-estradiol, and progesterone are key regulators of pigmentation, with higher levels of these hormones observed in women with melasma. Estrogen was shown to increase melanogenesis and support hyperpigmentation by stimulating melanogenic factors and increasing blood vessel numbers. Progesterone, while less studied, was found to stimulate melanogenesis in epidermal melanocytes and could potentially prevent melasma by reducing melanocyte proliferation without significantly affecting tyrosine activity. The review included 70 studies selected from an initial 98, following PRISMA guidelines.