Intro to HRT

From estrogen.fyi
Revision as of 23:50, 5 November 2023 by Plants (talk | contribs) (more writing)


Hormone replacement therapy, or HRT, is a relatively common medical treatment used in many contexts. Despite what many may think, this is not a new or experimental practice, nor is it exclusive to transgender individuals. Hormone replacement therapy has been used for over half a century, starting its use in the 1960s and becoming widely popular in treating menopause in AFAB (assigned female at birth) patients.

In this page, we will cover how HRT can be used in transgender or non-binary patents for gender affirmation. Certain hormones and medications can help feminize or masculinize even someone who has gone through an undesirable puberty.

This website is intended to be a resource for AMAB transgender individuals.

What can HRT do for me?

For AMAB transgender individuals who desire female secondary sex characteristics, estradiol hormone therapy is the most common practice: Lowering one's testosterone level and raising one's estradiol (AKA E2, the most biologically active estrogen) levels, targeting that of an average cisgender woman. Transfeminine HRT can also involve many other medications, such as progestogens or antiandrogens. This results in the feminization of the body. You will see changes such as healthier skin, female fat redistribution throughout your body, and breast growth.

Below is a chart outlining most of the common changes from HRT:[1]
Effect Permanence Expected Onset Maximum effect
Body fat redistribution Reversible 1-2 months 2-5 years
Decreased muscle mass Reversible 1-2 months 1-1.5 years
Decreased skin oil Reversible 1-2 months 1-1.5 years
Skin softening Reversible 1-2 months 1-2 years
Decreased libido Reversible days-weeks weeks-months
Decreased random erections Reversible days-weeks weeks-months
Erectile Dysfunction* Reversible days-weeks weeks-months
Breast Development Irreversible 2-6 weeks 2-6 years
Decreased testicular volume Variable 1-3 months 2-3 years
Decreased sperm production Variable 2-6 weeks 1-3 years
Decreased semen volume Veriable 2-6 weeks 1-3 years
Slowing of body & facial hair growth** Reversible 1-3 months 6 months-1 year
Voice changes*** N/A none none
Reversal of male pattern hair loss**** Reversible 1-3 months 1-2 years

*: Most individuals do not experience erectile dysfunction.

**: HRT will slow down body and facial hair growth, only laser/electrolysis can stop it entirely.

***: Transfeminine HRT does not cause an effect on an individual's vocal folds.

****: Male pattern hair loss can be prevented with HRT, but reversal of hair loss is rare.

So, what should I take, and how much?

Again, the goal with transfem HRT is to bring your hormone levels, most notably for feminization being estradiol and testosterone, from your current male range, to that of a healthy cisgender woman. On top of this, there are some medications and other hormones we will cover, progestogens, antiandrogens and other niche or specific medications such as hair loss treatments or more experimental methods for feminization.

Before we talk about specific medications, you need to have a basic understanding of the target hormone levels. For feminization to be effective, you should be within the level a premenopausal female would be:

100-200 pg/ml estradiol & <50 ng/dl testosterone.[2]

Blood tests are the only effective way to measure these levels and are extremely important in minimizing the risks of HRT and maximizing its effectiveness. We will talk about how to try and manage being in a situation where you cannot access bloodwork. This is not impossible, but we highly recommend against it.

Now, onto the fun stuff: what to take, and how to dose it.

Estradiol Monotherapy

The big one. Estradiol is the most biologically active estrogen and heavily contributes to feminization. On top of this, it contributes to the suppression of testosterone.

Estradiol-only HRT, also known as monotherapy, where estradiol provides both feminization and is dosed high enough to suppress testosterone into female ranges, is both possible and common. Monotherapy removes or reduces certain potential risks and side effects that one might see if they were on an antiandrogen, along with their estradiol dosage, to help with testosterone suppression, but usually requires more estradiol and is much harder to achieve with specific routes of administration such as oral or transdermal.

Injections are an excellent example of an ROI suitable for monotherapy. It's rare for someone to be unable to achieve proper levels through injections. There are several common esters used for injectable estradiol. These include Valerate, Cypionate, Enanthate, and the much less common but still worth mentioning Undecylate.

Dosages may be inconsistent on injections and vary wildly from person to person, though there is a reasonable starting dosage. If you have access to bloodwork, finding your dosage should be simple. Start with a sane dosage that works for most people, which we are about to cover now, and get a blood test immediately before a new dosage at the "trough" after a few weeks.

The biggest differences between the esters is their stability or half life. Estradiol valerate has a half life of 4-5 days[3], cypionate 8-10 days[4], and enanthate 5-7 days, though

  1. Mayo clinic: Feminizing hormone therapy https://www.mayoclinic.org/tests-procedures/feminizing-hormone-therapy/about/pac-20385096
  2. Wylie C Hembree, Peggy T Cohen-Kettenis, Louis Gooren, Sabine E Hannema, Walter J Meyer, M Hassan Murad, Stephen M Rosenthal, Joshua D Safer, Vin Tangpricha, Guy G T’Sjoen, Endocrine Treatment of Gender-Dysphoric/Gender-Incongruent Persons: An Endocrine Society Clinical Practice Guideline, The Journal of Clinical Endocrinology & Metabolism, Volume 102, Issue 11, 1 November 2017, Pages 3869–3903, https://doi.org/10.1210/jc.2017-01658
  3. Düsterberg, B, and Y Nishino. “Pharmacokinetic and pharmacological features of oestradiol valerate.” Maturitas vol. 4,4 (1982): 315-24. doi:10.1016/0378-5122(82)90064-0
  4. Thurman, Andrea et al. “Medroxyprogesterone acetate and estradiol cypionate injectable suspension (Cyclofem) monthly contraceptive injection: steady-state pharmacokinetics.” Contraception vol. 87,6 (2013): 738-43. doi:10.1016/j.contraception.2012.11.010