We all produce the sex hormones oestrogen and testosterone but people who were labelled female at birth usually have more oestrogen and people who were labelled male at birth usually have more testosterone.
In an adult female the sex hormones, which are mainly produced by the ovaries, are oestrogen, progesterone and small amounts of testosterone. Throughout the menstrual cycle the hormone levels vary from day to day, causing changes in mood, skin quality, appetite and sex drive.
In men, the hormone pattern is much simpler - they have about 10 times more testosterone than women, with lower levels of oestrogen and progesterone. The male hormone cycle takes 24 hours rather than a month, with the peak in the morning, although testosterone production is affected by activity such as playing (or even watching) sport.
Where do I start with hormone therapy?
You'll need to have medical assessments before you can start hormone treatment. You'll have blood tests to check your base levels of sex hormones as well as tests for liver function and cholesterol, as they can be affected by hormone treatment.
Testosterone isn't as easy to get into the body as oestrogen, so although there are testosterone patches, they have to be much bigger to get the right dose. The most common way to take testosterone is by injection, which will vary from being taken once per week to once every three months. An alcohol-based testosterone gel, which you rub on every day, is another option. There are also implants, which have to be replaced every six months, and gel tabs to stick on your gums.
If you find that you don't get on well with the method you start with, you can always talk to your endocrinologist to find a different form of testosterone to suit you.
Some people take hormone blockers until they are ready to start testosterone. These will dull down the female hormones and stop your periods without the effects that testosterone has.
Monitoring your hormone levels
It's vital to have your hormones monitored regularly so that your doctor can make sure your body is absorbing them.
It also means they can keep track of any side-effects and make sure you're taking the correct amount.
What will the hormone treatment do?
High doses of testosterone override the ovaries and cause them to shut down, which means your body essentially goes through male puberty and the menopause at the same time.
Like both puberty and the menopause, the changes are gradual and run a slightly different course for each person.
- Genital growth - the clitoris usually grows to an inch or two in length and will get thicker and have more noticeable erections.
- Voice changes - this usually takes a few weeks to start.
- Body and facial hair growth - this takes years to complete.
- Mood swings.
- Increase in appetite.
- Increase in libido.
- You can also expect an increase in muscle bulk but you are unlikely to get taller unless you are very young.
- Hair loss - this doesn't usually happen immediately but that will depend on your age and genetics.
- Your periods will stop - this may take months and you may have the occasional period for a while.
- Hot flushes.
- Mood changes.
- Skin changes.
- Reduced libido.
- Vaginal dryness.
- Itching and soreness may make sex uncomfortable and many people also get cystitis or thrush.
Some of these symptoms are on both lists and some can counteract each other, so it's impossible to predict exactly which changes you will get and when. Some people seem to sail through the process with none of the negatives while other people will be spotty, stroppy and moody.