Report: Hormone Therapy Poses High Risk Of Blood Clots For Males Transitioning To Females


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Grace Carr Reporter
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Transgender people transitioning from male to female have a much higher risk for blood clots than biological men and women, a Tuesday study found.

Biological males undergoing hormone therapy to become female face a high risk for venous thromboembolism — a kind of blood clot that poses a dangerous threat — according to a Tuesday study, “Cross-sex Hormones and Acute Cardiovascular Events in Transgender Persons.”

In the study, published in the Annals of Internal Medicine, researchers found that the risk of venous thromboembolism in transitioning subjects is nearly double the risk of men and women who aren’t going through any kind of hormone therapies.

The researchers gathered their data by following a set of transgender and non-transgender participants for roughly four years. The study included 2,842 males transitioning to become females and 2,118 females transitioning to become males. For every transgender participant in the study, 10 non-transgender male and female participants were matched to compare the prevalence of blood clots.

The study also shows that males who transition to become female don’t experience any of the benefits bestowed upon biological females, like a lower risk for heart disease. (RELATED: Man Undergoes Hormone Therapy To Breastfeed His Baby)

“This is the first large study that says we need to be aware of this (cardiovascular risk) and a lot of unanswered questions about duration, type and dosing of therapy have to be answered,” Dr. Alice Chang,  assistant professor at Rochester, Minnesota’s Mayo Clinic, told Reuters.

Senior author of the study, Michael Goodman, emphasized that the risks should be weighed against the benefits. “Our hope is people will understand we’re not trying to scare anybody. We’re just saying there are some questions that need to be answered to guide the therapy,” he told Reuters.

Chang also noted that she doesn’t expect the number of transgenders seeking hormone therapy to go down as a result of the study’s findings, because most transgender persons undergoing hormone therapy see it as vital to their wellbeing.

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