Transmasculine Guide: Risks

Risks/Side effects

Caution

Taking testosterone will likely cause infertility, though this is likely fully reversible if testosterone is stopped.

Danger

Testosterone is NOT a form of birth control and does NOT guarantee surpression of ovulation or fertility. If there is any chance that you could become pregnant, it’s important to use a reliable method of birth control/contraception to avoid unintended pregnancy.

For a full list of potential increased risks of certain health issues associated with transmasculine HRT, you can refer to this resource.

Most of the serious side effects are extremely low in absolute risk.

Polycythemia (high concentration of red blood cells in the blood) is a unique risk for transmascs taking any testosterone therapy. CBC (complete blood count) tests to monitor your hematocrit (red blood cell count) are recommended.

What should my CBC look like?

Polycythemia is defined as serum hematocrit (Hct) or hemoglobin (HgB) exceeding normal ranges expected for age and sex, typically Hct > 49% in healthy adult males. So there is little need to worry if you have Hct levels lower than that.

Aromatization

In all people, a small portion of the testosterone in their bodies is converted into estradiol (estrogen) through a process called aromatization. In most men, testosterone levels will typically remain within a range that does not cause a significant increase in estradiol levels, thereby mitigating any unwanted feminizing effects.

As a transmasculine person, it’s important to not take too much testosterone (please stay within recommended dosage guidelines) to prevent estradiol levels from getting too high (which can cause unwanted feminizing effects).

As long as you take reasonable dosages of testosterone and do not go over the recommended dosages, you are unlikely to deal with excessive aromatization.