Estradiol, Progesterone, Testosterone: What Each Does for Women

Women's hormones usually get discussed as one thing that drops at menopause. It is three hormones with three different jobs, and they fall on three different schedules. Knowing which one is low explains a lot of what a woman in her 40s or 50s is feeling.

Estradiol

Estradiol is the main estrogen. It keeps bone dense by slowing the cells that break bone down, keeps the lining of the vagina and bladder thick and elastic, helps the brain regulate body temperature, and has a favorable effect on cholesterol and blood vessels.

Through the 40s it does not fall in a straight line. It swings high and low, which is why symptoms come and go. After the final period, at an average age of about 51, it settles at a low level and stays there. Hot flashes, night sweats, vaginal dryness and faster bone loss follow from that.

Replacing it relieves hot flashes and night sweats for most women and slows bone loss. A woman with a uterus needs progesterone alongside it to protect the uterine lining. It carries real risks too, mainly blood clots with oral forms and a small rise in breast cancer risk with longer combined use, which is why the route and dose are chosen person by person.

Progesterone

Progesterone is made after ovulation, in the second half of the cycle. Its main job is preparing and then stabilizing the uterine lining. It also calms. One of its breakdown products acts on the same brain receptors as common sedatives, which is why progesterone helps sleep and why its loss often shows up first as lighter, more broken sleep and more anxiety.

Of the two cycle hormones, it usually falters first. Through the 40s, more cycles pass without ovulation, and a cycle without ovulation makes little progesterone. A woman can still have regular periods and good estradiol and be running low on progesterone in some of those cycles.

Replacing it, usually as micronized progesterone at night, protects the lining in women taking estradiol and often improves sleep on its own.

Testosterone

Women make testosterone too, in the ovaries and adrenal glands, at roughly a tenth of a man's level. It supports libido, energy, muscle and bone. It declines gradually from the 20s rather than dropping at menopause, so by the mid 40s levels are often about half of what they were at 25.

Low testosterone in women is often linked to low desire, low drive and difficulty holding muscle, though blood levels track those symptoms loosely. The best evidence for replacing it is for low sexual desire after menopause, and in the US that is done off label at a small fraction of a male dose.

A panel that checks only estradiol, or on one random day of a cycle, misses two thirds of the picture. We check all three, read them against the symptoms, and replace what is actually low.

If nobody has looked at this for you, it's worth a conversation.

This article is educational and is not medical advice.

Book a free discovery session with Dr. Wenhold