Use sex-hormone drugs only when a doctor prescribes them and checks you on a schedule. Do not buy them online, and do not raise the dose yourself

This does not discuss whether to use them. It only discusses how. Transgender women who use estrogen have clearly more blood clots in the vessels than people the same age, about 4 extra per 1000 people over 2 years, and about 17 extra over 8 years. This kind of risk has to be watched with regular follow-up. If you buy the drugs online and set the dose yourself, nobody is checking you.

Cost

Regular registration visits, plus blood tests. A few hundred yuan a year, and a few half-days.

Benefit

The researchers followed a group in the electronic records of Kaiser Permanente, a health-care group. There were 2842 transgender women and 2118 transgender men. Average follow-up was 4.0 years and 3.6 years. Each person was matched, on birth year, race, the clinic, and the time of joining, with about 10 times as many cisgender controls, 48686 cisgender men and 48775 cisgender women in all. Transgender women had more venous thromboembolism (a blood clot blocking a vessel) than the controls. Compared with cisgender men, at 2 years it was 4.1 cases per 1000 people (95% CI 1.6-6.7), and at 8 years it was 16.7 cases (6.4-27.5). Counted out, that is 4.1 extra cases among 1000 people over 2 years, and 16.7 extra over 8 years. Compared with cisgender women, the 2 figures were 3.4 (1.1-5.6) and 13.7 (4.1-22.7). Ischemic stroke (the kind of stroke in which a vessel is blocked) and myocardial infarction were, overall, close across the groups. Among transgender women who started hormone treatment only during the follow-up, the differences in venous thrombosis and ischemic stroke were clearer. The evidence on transgender men is not enough for a conclusion. The authors' conclusion was that "these results may suggest a need for long-term vigilance about the vascular side effects of estrogen in transgender hormone treatment."

Notes

The researchers themselves wrote down the shortcoming of this study. They could not find out how many people had bought the drugs themselves outside the hospital system. So the line of whether a person was on the drug was never drawn cleanly. That, in turn, is why drug use should sit inside regular follow-up. This study only looked at whether the blood vessels had an event. It does not answer whether hormone treatment should be used, or what good it does. That is a different set of evidence. Every use of sex hormones is the same, including contraceptive pills, menopausal hormone treatment, and testosterone supplementation. If you buy it online yourself, adjust the dose from posts on the internet, and never check clots or liver and kidney markers, the risk sits in the stretch where nobody is watching, not in the reason for using the drug. The regular path in China is the endocrinology department, or the matching specialty, of a proper medical institution, for an assessment, a prescription, and follow-up.

Sources · 2

1. Getahun D et al. (2018). Cross-sex Hormones and Acute Cardiovascular Events in Transgender Persons: A Cohort Study. Ann Intern Med. doi.org/10.7326/M17-2785
2. 国家市场监督管理总局 (2022). 药品网络销售监督管理办法（总局令第 58 号，第九条）. gov.cn/gongbao/content/2022/content_5717002.htm