Hormonal replacement therapies (HRT) have been used for decades to prolong youth. This used to be called taking hormones to help make you “feminine forever” and/or “healthy forever”.
This means that more youth, younger tissue time, is extended. By taking hormones from outside yourself and getting them into you.
Since HRT is now “out of favor” in standard of care, which is not in sync with the science, in my learned opinion, procedures to extend youth are being sought.
A new one is the transplantation of healthy ovarian tissue into aging women’s pelvis.