Oestrogen and blockers

Two people smiling at the camera Feminising hormone treatment for people assigned male at birth may involve the use of oestrogen (female hormone) and testosterone blocking medication.



Effects on the body

The effects of taking hormones may include breast growth and body fat redistribution to give a more feminine body shape. You may become less muscular. Body hair may grow more slowly and become softer, but facial hair growth may not change much (NHS funded facial hair removal treatment is available). Mood changes, both positive and negative, may happen but these don’t often require treatment.

Many who start taking hormones describe a sense of relief and of a feeling of completeness when then first take them. In addition, the physical changes often improve a person’s feelings of dysphoria which in turn means more body confidence and often more self-esteem. For many, this may be a defining point in their life and an important turning point. 




Female hormones will not change your voice. (Speech and Language Therapy is available). Female hormone treatment may affect sex drive. You will probably also be unable to get a full erection after some time on treatment. You are likely to become infertile (not able to have children) and even if you stop treatment you may still be infertile. You need to consider storing gametes (sperm) before treatment if you wish to have biologically related children in the future. Although hormones are likely to make you infertile, there is a possibility that if you engage in penile-vaginal intercourse your sexual partner could become pregnant so you should use contraception if this is a possibility. 



Blood tests

It is important to have regular blood tests as there may be changes to things like liver function and prolactin which could require more investigation. For this reason, we recommend that you have your blood tested regularly so that we know if there have been any changes. 



Other possible risks

There is a risk of developing DVT (also called ‘deep vein thrombosis’ or ‘blood clots’) on this treatment. This is important as it may result in serious illness or even death, particularly if it is not treated quickly. If you develop unexpected pain or swelling (usually in your leg), sudden chest pain, shortness of breath and cough you should see a doctor very quickly. For example, you should go to the Accident & Emergency Department (A&E), a Walk-in Centre, or see your GP as an emergency on that day. The chance of getting a DVT is greater if you smoke or if you are overweight.

There may be long-term risks in taking feminising hormone treatment. These are not fully known but include cardiovascular risks such as heart attack and strokes which can make you very ill or even cause death. These risks will be increased if you are overweight, smoke, have high blood pressure, high cholesterol levels, or diabetes.

If you are on a testosterone blocker or have had surgery to remove your testicles then your testosterone levels will be low. If your testosterone level is low you must take oestrogen treatment regularly. You must also have blood tests to make sure you are taking enough oestrogen. Otherwise there is a risk that you could develop osteoporosis (also called thinning of the bones) which may increase the risk of breaking your bones. 



Breast cancer

The risk of breast cancer in people assigned male at birth is low but may be higher than that of cisgender (non-trans/non-binary) men. You should go for regular breast screening when asked to. The risk of prostate cancer may be less than for cisgender men, but your GP should be aware that it is still a risk and should screen or investigate you as usual. 



Stopping treatment

You may stop this treatment at any time but some of the effects such as breast growth and infertility may not be reversed if you do. It is important to have regular blood tests and to attend appointments at our clinic to reduce the chances of unwanted effects.

If you are unable to attend appointments regularly we may no longer support your treatment and your GP may decide to stop your treatment.