Blood testing is highly recommended, but not absolutely mandatory¹ — especially if not particularly affordable or feasible.
It is recommended to do your first blood test within the first 3 months, and then adjust your dosage if necessary. If you change your dosage, try to retest again within 3 months. If your levels look good, blood testing frequency can be reduced to just once a year.
Here are some sources of private blood testing² if you cannot access blood testing through the medical system:
Get your estradiol (E2) and total testosterone (T) tested every time. Get your blood taken as close as possible to your next scheduled injection/dose (Test your blood as far away as possible from a previous dose, right before your next scheduled dose. Preferably the day of your shot, or the day before).
Your blood levels of estradiol and testosterone when taken at this time are called ‘trough levels’, because they are the levels of E2 and T that are present in your body at the lowest point in your HRT dosing regimen. Trough levels most useful for injection monotherapy; for determining if your testosterone is adequately suppressed at the lowest point of your injection cycle.
The most essential component of transfeminine HRT is to get total testosterone (T) below 50ng/dL and estradiol (E2) above 100pg/mL
International sources for blood testing are unfortunately rare. You can try to find local private blood testing services or ask a doctor if they can provide you with the appropriate blood lab requisition forms. Unfortunately, depending on your circumstances, you may be unable to find a way to get blood tests.
Get your estradiol (E2), total testosterone (T) and complete blood count (CBC) (also referred to as full blood count/FBC) tested every time. Get your blood taken as close as possible to your next scheduled injection/dose (Test your blood as far away as possible from a previous dose, right before your next scheduled dose. Preferably the day of your shot, or the day before).
Your blood levels of estradiol and testosterone when taken at this time are called ‘trough levels’, because they are the levels of E2 and T that are present in your body at the lowest point in your HRT dosing regimen.
What should my total testosterone (T) reading be?
The Endocrine Society’s 2017 clinical guidelines for transgender HRT recommend that trans men maintain “testosterone levels in the physiologic normal male range”, a range which is typically given as 300–1000 ng/dL. Slightly higher or lower testosterone levels above or below this range are not something to worry about unless your estradiol levels are also too high.
What should my estradiol (E2) reading be?
The typical range for adult males is 10 – 50 pg/ml although this varies due to age and individual factors. Try to aim within this range, although slightly higher levels are not something to worry about. Try to keep your estradiol under 70pg/mL.
What should my CBC look like?
Polycythemia is defined as serum hematocrit (Hct) or hemoglobin (HgB) exceeding normal ranges expected for age and sex, typically Hct > 49% in healthy adult males. So there no concern if you have Hct levels lower than that. If your levels are elevated, donating blood or reducing testosterone dose can treat polycythemia.
If your red blood cell (RBC) and hematocrit are above reference ranges on your CBC test, you may be at elevated thrombosis (blood clot) risk. You can donate blood or lower your dose to reduce this risk.
Occasional Liver Function Tests (LFT)/Liver enzymes, Clotting factors test, and Lipid profile test (cholesterol, triglycerides) can be useful to monitor certain health risks associated with testosterone therapy. Though these risks would usually only be relevant at excessively high dosages.
International sources for blood testing are unfortunately rare. You can try to find local private blood testing services or ask a doctor if they can provide you with the appropriate blood lab requisition forms. Unfortunately, depending on your circumstances, you may be unable to find a way to get blood tests.
1
(Only if you’re transfem) However, I strongly recommend regular blood tests (every 3 months) to get liver function tests (ALT/AST) if you are taking bicalutamide, due to the extremely low but still present risk of severe liver toxicity. You can stop these tests after about a year or so (if your liver enzymes are normal on bica after a year you’re fine).
2
Most private blood testing lets you print off a requisition form, which you can bring to a local blood lab to get your blood drawn. You don’t have to mail anything in or take your blood at home. In some countries like the UK you can get a test kit to take to an appointment.