Hormones Do What?: How Hormone Replacement Therapy (HRT) Impacts the Menstrual Cycle

Hormone Replacement Therapy (HRT) has a variety of uses, and is often used by transgender and non-binary humans to help them experience gender-affirming physical changes. Hormones do a lot in our bodies, influencing everything from hair growth (or loss), sex drive, and mood, to fat distribution and the menstrual cycle. This post addresses some of the common questions that people have about HRT and the menstrual cycle, including information about both feminizing and masculinizing hormones. If you're curious about how hormone replacement therapy impacts the menstrual cycle, read on!

If you have other questions about HRT, you can speak with a care provider (often a therapist or a general care practitioner can help get you started or point you in the right direction) or talk to others who have experienced hormonal transition (try a Facebook group, a gender doula, or local/national/global organizations that serve trans individuals).

Feminizing vs. Masculinizing Hormones

There are a variety of HRT regimens that people use to achieve gender-affirming effects. Different people want different things from their HRT and so type and dose of hormone treatment will vary from person-to-person. Gender is truly a spectrum, a galaxy, and labels like "masculine" and "feminine" aren't all that helpful. Thick or coarse hair can be feminine, soft skin can be masculine, and so on. However, when hormones are classified as "feminizing" or "masculinizing", that generally means that feminizing hormones are taken by people who were assigned male at birth or have testosterone-dominant hormones in their system and that masculinizing hormones are taken by people who were assigned female at birth or have estrogen-dominant hormones already in their body.

Feminizing hormones often include several drugs or hormones, including anti-androgens or testosterone blockers that decrease the body's production of testosterone as well as estrogen that will support the body in things like fat redistribution, breast growth, softer skin, smaller pores, slower growth of body hair, genital change, etc.

Masculinizing hormones typically just consist of testosterone, which supports the body in facial and body hair growth, increased muscle mass, vocal changes, body fat redistribution, etc. 

Care providers may recommend progesterone in addition to other HRT for both people taking both feminizing and masculinizing hormones. For people looking to develop breasts, progesterone can cause additional breast growth, and for people seeking to stop a menstrual cycle, progesterone can help suppress ovulation and menstruation.

That brings us to the effects of HRT on the menstrual cycle. Some people wonder whether feminizing hormones can cause a menstrual cycle for transfeminine people and non-binary humans who were assigned male at birth. Unfortunately for the folks who hope this to be true, this isn't possible. To understand why not, as well as to understand more about the effects of masculinizing hormones on the menstrual cycle, let's take a look at what a body needs to have a menstrual cycle.

Elements Necessary for a Menstrual Cycle

To have a menstrual cycle, a person needs several elements. For ease of understanding, you need both the “hardware” and “software” necessary for menstruation, both the organs and the hormones that tell those organs to ovulate and menstruate. Those organs are ovaries that produce eggs, a uterus for an endometrial lining to build up on, and an opening for that lining to shed from the body. The hormones necessary for a menstrual cycle are estrogen and progesterone. Estrogen encourages the body to ovulate, and menstruation typically happens 12-18 after ovulation if the egg(s) released from the ovaries were not fertilized with sperm. 

If all of those elements are in play, a menstrual cycle is likely to happen. If not, the body will not ovulate or menstruate. Because both organs and hormones are necessary to menstruate, if someone does not have those organs (because the organs were removed or they were born without them), they won't menstruate.

Effects of Masculinizing HRT on the Menstrual Cycle

Often, the testosterone that people take as a masculinizing hormone affects the body's production of estrogen and stops the menstrual cycle. This isn't always the case, however, so people might take progesterone or use a hormonal birth control to suppress the ovulation and menstruation process. Even if menstruation doesn't happen, some people report menstrual-like symptoms, like cramps, bloating, or emotional changes that seem to happen in a cycle. Others might choose to have the organs responsible for menstruation removed, and then they'd no longer have a menstrual cycle, no matter what hormones were in their body.

Other than stopping the menstrual cycle altogether, other effects of testosterone on this physical process are:

• Change in the length of your cycles (often longer)
• Irregular menstrual cycles
• Increased cramps, discomfort, or pain

Finding the hormones that are right for you and your body can be tricky. Talk with your care provider(s) about your goals for HRT and ask them to help you create the effects that are important to you while avoiding (as much as possible) the side effects that you don't want to experience. If you're taking testosterone as a masculinizing hormone and are experiencing longer, painful, or irregular cycles, you can also talk to someone who specializes in menstruation in addition to your primary care providers, like a doula, midwife, herbalist, acupuncturist, or other health practitioner. Here's to feeling good in your body, mind, and gender!

Beth Rich is a queer educator and full-spectrum cycle doula who works at the thresholds and intersections of menstruation, family-building, pregnancy, birth, loss, and other life transitions. They're a non-binary human who's excited to talk about bodies, periods, birth, and sex in language that holds space for all of us. Discover more of their work at thebethrich.com or on Instagram @thebethrich.

Photo by Zackary Drucker for The Gender Spectrum Collection.