Ongoing testosterone treatment is likely to affect your monthly cycle, by reducing or stopping it entirely. It is still important to consider the need for smear tests and sexual health checks (including sexually transmitted infections). Your GP or local sexual health clinic can help with this.
Testosterone treatment should eventually stop your monthly cycle altogether. If you would like to address this sooner, we can look at adding a puberty blocker to your treatment, or by maximising testosterone therapy to cisgender male levels.
Some transmasculine people also use the progesterone only pill or injection (such as cerezette or cerelle) to control their monthly cycle.