Apnea is associated with reduced estrogen and testosterone levels in aging individuals.

“One of the main behaviors that's been shown to be associated with poor levels of estrogen relative to age-match controls for people with ovaries or lower levels of testosterone compared to age-match controls for people with testes, is apnea, apnea has everything to do with under-breathing and the buildup of too much carbon dioxide in the body, there are other effects of apnea as well, but if there's a consistent literature in this whole story about aging and reductions in hormones and general health and reductions in hormones, it's apnea.”