The cellular and molecular mechanisms underlying the effects of aging on human cutaneous wound healing are poorly understood, and the possible role of reproductive hormones in this process has never been investigated. We report that aging in healthy females was associated with a reduced rate of cutaneous wound healing, but an improved quality of scarring both microscopically and macroscopically, and with reduced levels of transforming growth factor-β1 (TGF-β1) immuno staining and steady-state mRNA in the wound. These age-related changes were reversed by the systemic administration of hormone replacement therapy (HRT). Moreover, ovariectomized young female rodents exhibited a marked delay in repair of acute incisional wounds, which was reversed by the topical application of estrogen. The cellular mechanism underlying these changes appears to involve an estrogen-induced increase in latent TGF-β1 secretion by dermal fibroblasts. These results suggest that both the rate and quality of wound healing depend on reproductive hormone levels.