The following is in response to a question from a reader, and applies to transfeminine persons after gender reassignment surgery (GRS/SRS) or orchiectomy.
[ For a detailed run-down of the transfeminine social and medical transition processes, see What is gender transition? For a detailed list and discussion of the many considerations in transfeminine medical transition (including hormone replacement therapy — HRT), see Transfeminine Medical Transition — Costs & Considerations. ]
The usual disclaimer applies: I am not a medical professional, and the following does not constitute medical advice. This is my opinion based on my personal experience, the collective experience of other women with whom I’ve corresponded, and my readings in the medical literature and personal anecdotes. This is not medical advice; see your doctor.
This is about your body and the rest of your life: educate yourself and own the process. For planning a hormone regimen I recommend doing a lot of reading, and getting assessments from two different doctors specialising in working with trans women, as there is still a lot of variation in opinions and protocols, and a few are very…uh… strange.
With all that said, here are my lay opinions:
- After GRS or orchiectomy you no longer need testosterone blockers (and shouldn’t take them). Blockers are hard on the body, and you don’t want to be taking them for ages.
- Post-surgery you need a couple rounds of blood-levels to adjust oestrogen to the midrange of female normal. Possibly the upper range if you’re still developing (typically 3–5 years).
- Oral administration of oestrogen can be hard on the liver, and is associated with a higher risk of thromboembolism, especially in older women. Transdermal delivery methods minimise these risks. Many (myself included) feel that injections are best for transitional development, and other non-oral options (e.g., patches) for maintenance thereafter. (For a discussion of oral vs sublingual oestrogen, see note .)
- There is an opinion that having oestrogen levels too high can actually inhibit good development, but support for this is sparse.
- After surgery one’s HRT situation is the same as for menopausal cis women. Associated health risks may be lower for trans women who start oestrogen later in life.
- As with cis women, a loss of oestrogen will result in loss of subcutaneous fat, which can then reveal underlying masculinised bone structure. Breast size can diminish. Body hair can increase, eyebrows become bushier, and head hair can thin. You also lose some of the emotional spectrum associated with oestrogen.
I experienced all these (except body hair, which thankfully I never had), and went back on oestrogen earlier this year after a 10 year hiatus — my emotions returned, and my breasts plumped back up; I am impatiently awaiting improvements to my face and hips. Personally, I don’t recommend stopping HRT.
- There may or may not be benefit to progesterone, either during or after transition. Some doctors and trans women feel that there is benefit, but I’ve not been able to find any support pro in the research literature, thus far. (For an opinion in favour, see footnote .)
- Metabolism changes in the absence of testosterone (with or without surgery), and weight gain can become a problem. Generally speaking, fewer calories and/or more exercise are necessary to maintain a consistent weight. This can become even more of an issue as one proceeds through ones 30s and 40s.
This has been my own experience and my observation of other women. My recommendation is to monitor weight fairly carefully (whilst resisting obsession), and adjust as needed before it becomes a problem.
 With regard to oral vs sublingual oestrogen, reader Brianna Nicole Schuman writes:
The only clarification I would add is to separate oral (swallowed pill) and sublingual (under the tongue pill). They have vastly different results in terms of both absorption and liver impact. Pure oral pretty much should never be used in general.
Research on the difference in liver functioning between oral and sublingual pill methods is difficult to find, but practice suggests that in theory the impact should be lower with sublingual, though not necessarily absent.
I used to [have references] somewhere…I know I have the absorption rate chart handy; that’s a 15% swallows vs 75% sublingual. The liver attack rate though I’ll have to dig up.
There are definitely arguments over toxicity on sublingual. I know it’s not zero; my own results showed minor impact compared to pre-E2. It’s the question of how different. It probably varies from person to person depending on how well they follow procedure for sublingual…
 My source for the opinion on too-high oestrogen levels is a set of M2F guidelines from the London GIC, which state, on page 4:
We know from treating genetic females that have not had a natural puberty that if too much oestrogen is given too quickly then breast development is not normal and you may end up with small cone shaped breasts not a natural female contour.
No reference for this is given in the document, and I’ve not been able to find support in the medical literature (which does not mean that such support does not exist, only that I’ve not found it).
 The following is the best general discussion of progesterone vis-à-vis trans that I’ve seen [from the page Overview of feminizing hormone therapy, section Antiandrogens — other approaches, of UCSF’s Transgender Health Guidelines website (link below)]:
Progestagens: There have been no well-designed studies of the role of progestagens in feminizing hormone regimens. Many transgender women and providers alike report an anecdotal improved breast and/or areolar development, mood, or libido with the use of progestagens.[17,18] There is no evidence to suggest that using progestagens in the setting of transgender care are harmful. In reality some patients may respond favorably to progestagens while others may find negative effects on mood.
Read the rest of that page if you’re considering progesterone.
I highly recommend UCSF’s Transgender Health Guidelines as possibly the best resource available on the net; and Maddie Deutsch, the unstoppable force behind the Center which runs the site, is just an outstanding person, doctor, and advocate. ❤
 My friend and fellow author, Natasha Troop, writes:
I started progesterone post-op. I found some good studies showing it had benefits taken then and, for me, they have proved true.
I don’t have all the articles I had back in 2012 when I started taking progesterone…here are some relevant pieces I found:
http://www.smithrexalldrug.com/assets/study29.pdf (not trans specific, but does offer info on mitigating factors of progesterone in hrt)
More interesting treatment info (note I take prometrium):
There are a lot of confirming studies and documents out there, but they all are pretty much in line with my experience — that my mood stabilized quite a bit post-op and I had increased nipple and breast development. I take all of my hrt orally to no ill effect (estradiol is sub-lingual). My labs always come back healthy.
 In subsequent correspondence, for those subject to the American medical coding system, Natasha adds:
I think the key to HRT at any stage is to stay current on your blood work. Note that, especially after GRS, if your doctor codes your work as 302.50, tell them to change it to the coding for post-menopausal. Should insurance companies return to their previous stance of not paying trans-related claims, that 302.50 will disqualify the coverage. If your doctor won’t change the coding, find a new doctor.
I agree with Brianna regarding the difference between oral and sublingual. One should note that the pill they provide will not be designated as “sublingual,” but should be taken that way. It takes all of a minute for it to dissolve.
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