Estrone is a natural, steroid hormone that belongs to the group of sex hormones known as estrogens. It is primarily produced in the ovaries, although smaller amounts are also synthesized in the adrenal glands and other tissues. Estrone plays a crucial role in the female reproductive system and is a key component in regulating various aspects of a woman's menstrual cycle and fertility.
During a woman's reproductive years, estrone is one of the three main estrogens, along with estradiol and estriol. It is responsible for promoting the development and maintenance of female secondary sexual characteristics, including breast development and the regulation of the menstrual cycle. Estrone levels fluctuate throughout the menstrual cycle, with higher concentrations during the first half (follicular phase) and lower levels during the second half (luteal phase).
After menopause, when ovarian function decreases, estrone becomes the dominant estrogen produced by the body. It continues to have various effects on bone density, skin, and other tissues, but its levels are significantly lower than during the reproductive years.