THE LIBRARY

From the "What's Whats" to the "How-To's," discover answers to your queer and trans healthcare questions from FOLX clinicians, team, and community.


The articles contained in the the FOLX Library consist of generally available information and do not constitute medical advice, diagnosis, treatment.

Estrogen

BASICS

BASICS

BASICS

BASICS

BASICS

BASICS

BASICS

BASICS

BASICS

BASICS

BASICS

BASICS

Estrogen is the primary hormone typically found in people with XX chromosomes, or assigned female at birth. The three major estrogens are estrone, estradiol, and estriol, and they are largely responsible for the development and regulation of the ovarian reproductive system, and secondary sex characteristics such as breasts or hips.

Estradiol is the most commonly prescribed form of Estrogen for HRT. It both reduces testosterone levels in the body, and promotes the development of secondary sex characteristics such as breasts, hips, facial softening, and more.

Firstly, "androgens" are hormones that regulate the development of sex characteristics. Those born with XY chromosomes and/or assigned male at birth often have high levels of androgens, while those born with XX chromosomes and/or assigned female at birth often have low levels of androgens (and high levels of estrogens). So anti-androgens work to block the effects of androgens such as testosterone. We offer anti-androgens as Spironolactone, Finasteride, and Dutasteride.

Spironolactone is the most commonly prescribed testosterone-blocker (aka "anti-androgen") for those undergoing estrogen HRT.

Finasteride is a testosterone blocker (aka "anti-androgen") sometimes prescribed as a supplemental anti-androgen.

Dutasteride is a testosterone blocker (aka "anti-androgen") sometimes prescribed as a supplemental anti-androgen.

Prometrium (micronized progesterone) or Provera (medroxyprogesterone) are the two options for progesterone, and both are pills taken daily. What is known is inconclusive: some studies suggest that progesterone does not help with breast development or body fat redistribution, and it may increase the risks of estrogen. Some clinicians have found that progesterone may be helpful to improve breast or areolar development only if you don’t achieve full breast development with estrogen. There may be some testosterone blocking effect of progesterone. Some people also report improvement in mood and libido, while others report a worsening. Overall, the response to progesterone is often very individualized, with some noticing benefits and others not noticing any benefits or noticing only negative effects. If unclear about which progesterone to take, we recommend Prometrium since it may be safer than other forms of progesterone.

FOLX offers three main routes for Estrogen:

  • Oral: A pill form of estrogen that is usually dissolved under your tongue (sublingual), taken once to twice a day.
  • Injectable: A sterile liquid form of estrogen  (suspended in oil) that is injected into the body with a needle
  • Transdermal/Patch: An adhesive patch that allows estrogen to be absorbed through your skin and into your bloodstream, applied every 3-4 days.

Some people also choose to take an anti-androgen, which FOLX has a few different routes for.

No, you don’t. However, anti-androgens work well with estrogen by blocking the masculinizing effects of testosterone. It also helps decrease the risks of HRT by allowing for lower doses of estrogen.

You are your best judge on what feels comfortable! You can read through more on all FOLX estrogen routes here.

If you're on estrogen, we take labs for estrogen and testosterone levels. If you're also taking spironolactone, we also keep an eye on potassium levels. You can get the full low-down on labs here.

You can take a missed dose as soon as you remember. However, if it’s close to the time for your next dose, skip the missed dose and continue taking your medication as prescribed. Don’t take two doses at the same time. 

Not a problem! Between injections, pills, and patches, you have options, depending on what is feeling best for you, regardless of how long or short you've been on HRT. You read more about the routes here, or can speak with one of our clinicians about finding the best new way for you.

EFFECTS

EFFECTS

EFFECTS

EFFECTS

EFFECTS

EFFECTS

EFFECTS

EFFECTS

EFFECTS

EFFECTS

EFFECTS

EFFECTS

It varies from person to person, but you can read more on that here.

Nope! Your body, your preference. For any top surgeries (breast augmentation, augmentation mammoplasty, implants) or bottom surgeries (penile inversion, rectosigmoid vaginoplasty, non-penile inversion, etc) you do not need to be on estrogen.

Estrogen can result in a decrease in muscle mass and a redistribution of body fat, especially to the hips and thighs. You may also see a possible decrease in muscle definition in the arms and legs as body fat increases right below the skin, making it look "softer," along with the potential for some loss of muscle mass. Because muscle has a higher weight density than body fat, there can be fluctuation of numbers on a scale (this is neither good nor bad, it just is). The maximum extent of these changes are often seen within 1-2 years, depending on dose. Finally, we also want to state that "fat" is not a bad word! Fat is a necessary part of everyone's bodies!

Estrogen can stop further hair loss on your head, but it won't help re-grow hair that has already been lost. However, we have additional medications that may be able to help you with that.

Within anywhere from two months to six months (sometimes longer, sometimes shorter) you should breast tissue development, however exact size of breast tissue development can't necessarily be predicted. The maximum extent of these changes are often seen within 1-2 years, depending on dose. Read more on that here.

Within anywhere from three to six months of beginning estrogen (sometimes longer, sometimes shorter), you should see a redistribution or development of body fat to your hips, though total amount or size of hips can't necessarily be predicted. The maximum extent of these changes are often seen within 1-2 years, depending on dose. Read more on that here.

No, estrogen will not make you any shorter or taller.

While estrogen won't affect your facial bone structure, it can affect your face's texture (i.e. softness, fat redistribution, oiliness) making it "softer." Read more on that here.

If beginning estrogen after puberty, it will not have an impact on your voice's pitch or tone.

LONG TERM

LONG TERM

LONG TERM

LONG TERM

LONG TERM

LONG TERM

LONG TERM

LONG TERM

LONG TERM

LONG TERM

LONG TERM

LONG TERM

Before we get into it, we want to let you know that this is a very common question! Some folks' gender discovery takes them down this path for a while, and then they head elsewhere, and that is great! For reference, however, the effects of estrogen therapy that are usually reversible are: softening of skin, body fat redistribution, decreased muscle mass/strength, thinned/slowed growth of body and facial hair, and male pattern baldness. Usually variable or irreversible effects of estrogen are: breast growth, decreased testicular volume, decreased libido, decreased spontaneous erections, decreased sperm production or infertility, erectile dysfunction. You can read more on changes from estrogen here.

People who take estrogen or progesterone can see an increase in risk for breast cancer, but still are likely to have a reduced risk compared to those born with XX chromosomes. It is often recommended to plan for annual screening after the age of 50.

SEXUALITY

SEXUALITY

SEXUALITY

SEXUALITY

SEXUALITY

SEXUALITY

SEXUALITY

SEXUALITY

SEXUALITY

SEXUALITY

SEXUALITY

SEXUALITY

As far as sexual function goes, estrogen can result in a decreased libido (sex drive), a decrease in spontaneous erections, and also less firm erections. These are more likely to occur if you're also taking a testosterone-blocking agent such spironolactone.

It can, but that's not absolute. Erections and erectile function are driven by testosterone. When testosterone levels decrease in the body with estradiol use (especially when used together with a T blocker), it can cause erectile dysfunction. There are many other causes of erectile dysfunction related to both your physical and mental wellbeing and health. 

For the most part, yes! PrEP does not decrease the effectiveness of your hormone replacement therapy.

However, one study has shown that taking estrogen may decrease the amount of PrEP in the bloodstream, and therefore may decrease how effectively PrEP protects you from acquiring HIV. While there are still a lot of studies that need to be done to follow-up on this, we recommend making sure you're taking you PrEP as consistently as possible, and continuing to use barrier methods in addition to PrEP.

We do not recommend anyone who is taking estrogen to use PrEP-on-demand (PrEP 211) since that is not as effective as continual daily PrEP, and given the possible decrease in PrEP with estrogen, may not provide adequate protection against HIV. Read more on that here.

If you are having the kind of sex that could result in a pregnancy and you don't wish to do so, then YES. Talk with your provider about birth control for your body, or for your partner(s) body. Read more on that here.

Erections and erectile function are driven by testosterone. When testosterone levels decrease in the body with estradiol use (especially when used together with a T blocker), it can cause erectile dysfunction (ED). ED is when someone stops being able to have as much of an erection as they would like, or to have an erection for as long of a time as they would like. If the ED is caused by low testosterone levels from HRT, there are some medications that you can use that work by increasing your blood flow which leads to an erection. The most common medications are Sildenafil (Viagra) and Tadalafil (Cialis), but there are many other options that someone might choose depending on their goals, past experiences with these medications, or if they are on certain medications. We can certainly help you decide which option is best for you!

Yes, you can (if your partner has a uterus, and is ovulating). If you are having this kind of sex and you don’t want to create a pregnancy with a partner, you can talk with your provider about birth control for your body, or for your partner(s) body.

For people with a partner(s) with a uterus: if you have a partner who is on testosterone for HRT, that hormone does NOT act as birth control. Your partner may not even be getting monthly bleeding anymore, but could still be ovulating. Read more on this here.

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