Feminizing Hormones

By Nick Peplow·Founder and editor

Last reviewed 27 September 2026· How this site is researched

Feminizing hormone therapy has two jobs. It adds estrogen, called oestrogen in the UK, which drives the changes most people are hoping for. It also brings testosterone down, so estrogen isn't working against it. Some people get both from estrogen alone. Most take a second medicine, an anti-androgen, to handle the testosterone side. A smaller number add progesterone, which is the most argued-over part of the whole subject.

The estrogen almost everyone is prescribed now is estradiol, the same hormone the ovaries make. It comes as tablets, patches, gel or injections. The form matters more than people expect, mostly for clot risk and for how steady your levels are, and estrogen goes through each one. Which anti-androgen you're offered depends heavily on the country. US clinics mostly use spironolactone, UK and European prescribers have leaned on cyproterone acetate or injections that switch testosterone off at the source, and anti-androgens explains why they differ.

Hormones work slowly, because what they set off is a second puberty. Skin and libido change within weeks to months. Breasts and fat take years. Some things never change at all: estrogen does nothing to a voice that has already dropped, to height or bone structure, or to beard growth that is already established. What changes, and when sets out the rough timeline so you know what you're waiting for and what you'll need something else for.

The risks are real and mostly manageable. The main one is blood clots, which is why smoking, age and the form of estrogen matter so much, followed by a handful of things the routine blood tests are there to catch. Risks and side effects covers what to watch for and what needs a same-day call.

I'm not a doctor and I've never taken hormones. What I know comes from a decade of coordinating trans women through surgery in Bangkok, where hormones come up at nearly every appointment: which ones someone is on, what their levels look like, whether to pause before an operation. The people who had a prescriber who explained things were calmer about all of it than the ones who'd worked it out from forums.

If you haven't started yet, getting hormones covers the routes to a prescription, from informed consent clinics to gender clinics, and what it costs. If you're after some changes and not others, non-binary and low-dose HRT is the page for that.

None of this is medical advice. It explains what the medicines are and what they do, so you can have a better conversation with the person prescribing them. Don't start, stop or change a dose without them.