Hormones 101


Hormones 101

What are hormones? What do they do?

Hormones are chemicals that your body makes, which help regulate certain things that your body does. They help to regulate your growth, metabolism, and fertility. They also play a big role in the development of so-called “secondary sex characteristics”, such as breasts, facial hair, and the distribution of fat in the body. And they can affect your immune system and your mental health!

While everyone has hormones, they can vary a lot from person to person. Some people’s bodies might make a lot of estrogen, but very little testosterone, or vice versa. Sometimes people say that testosterone is “male” and estrogen is “female”, but most people have both of these hormones naturally, regardless of what their assigned sex at birth is.

Why take hormones?

Doctors may prescribe hormones as medication for a lot of different reasons. When someone’s body makes too much or not enough of a certain hormone, it can cause health problems like depression, fatigue, extreme changes in weight, a weakened immune system, and other issues.

For some transgender people, taking hormones is part of their transition process. Because hormones affect secondary sex characteristics, they can be useful when someone wants to develop breasts or facial hair, change the shape of their body, or slow down puberty. This can help with dysphoria, and make navigating social situations easier.

While hormones can be an important part of a trans person’s healthcare, whether or not someone takes them is a personal and confidential medical decision. Not every trans person chooses to take hormones, and taking them doesn’t make someone any “more” or “less” trans.

What is HRT?

There are three main types of hormones that trans people might take: estrogen, testosterone, and puberty blockers. Estrogen and testosterone are sometimes called hormone replacement therapy, or HRT.

  • Puberty blockers are also called GnRH agonists. They do what the name says: they “block” the body from producing hormones that cause puberty. Taking puberty blockers can stop someone from developing breasts, facial hair, and other traits they might develop as they age. This can be useful for young trans people who want to avoid developing those traits because of dysphoria and social prejudice. It can also make some parts of medical transition, like surgery, easier later on. Injections and implant are the two main ways of taking puberty blockers.
  • Estrogen is also sometimes called a “female” hormone, but people who aren’t women produce estrogen, too. Estrogen causes breast growth, fat redistribution, and softens the skin. Most doctors prescribe it with something called an anti-androgen. Anti-androgens block the production of testosterone. This can stop hair loss and facial hair growth. It also lets people take smaller doses of estrogen, which can be harmful in very large amounts. People may use estrogen as a pill, patch, injection, or cream.
  • Testosterone is sometimes called a “male” hormone, but people who aren’t men produce testosterone, too. Testosterone causes facial hair growth, fat redistribution, and can make the voice lower. Some people report that it increases their sex drive and makes their skin rougher, too. It is sometimes taken with estrogen blockers, but not usually. People may use testosterone as a pill, patch, injection or cream.

People who take HRT may do so for any number of reasons, including dysphoria and avoiding discrimination. But not all trans people choose to take hormones, and that’s okay.

Are there any risks to taking hormones?

Just like any other medication, HRT and puberty blockers can have side effects for some people. If someone is taking estrogen and anti-androgens, they may need to watch out for signs of liver damage or blood clots.

Testosterone can cause high cholesterol, and increase someone’s risk for type 2 diabetes. That’s why it’s important for people who are taking hormones to see a doctor if they feel unwell, and for regular checkups — just like they would if they were taking any other kind of medicine over a long period of time.

But most people who take hormones don’t develop these things, and for people who choose to take hormones, the benefits can greatly outweigh the risks. For example, studies show that young trans people who have the option of taking puberty blockers are less likely to experience depression and anxiety as a result of dysphoria. If someone is taking hormones and they need to stop, most of the effects are reversible. Only a few like breast growth and clitoral enlargement are permanent.

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