Carriers bleed too. Now it's in writing.
So many of us grew up hearing the same line: carriers don't bleed. Hemophilia was a boys' disease. Women were just the ones who passed it on.
A new "How I Treat" paper in Blood, one of hematology's leading journals, says what our bodies have been telling us all along. Carriers bleed. Some women and girls have hemophilia. And the old myth is still delaying diagnosis.
What the paper says
There's language for us now. If your factor VIII or IX is below 40%, you are a woman or girl with hemophilia. If your levels are normal but you bleed more than you should, you're a symptomatic carrier. These terms were set in 2021, almost 100 years after the first report of a carrier with excessive bleeding.
Normal levels don't rule out bleeding. Carriers with near-normal factor levels still have joint bleeds and heavy periods. Your number is one piece of the picture, not the whole thing.
It often starts with periods. Heavy menstrual bleeding is the most common symptom. Heavy bleeding from a girl's very first period is a strong signal to test.
Iron matters. The authors recommend regular ferritin checks, not waiting for hemoglobin to drop.
Pregnancy can hide a low factor IX. For hemophilia B carriers, a level tested during pregnancy can read higher than your true baseline.
Two stories that stopped me
A 4-year-old girl had a knee bleed. Her dad has hemophilia A. Her doctors had to ask whether a girl could even have it. She did.
A 19-year-old had heavy periods from age 12. She was told it was stress. Her grandfather had hemophilia, and her family was told it only affects men. It took seven years, and a trip to the ER, before a women's clinic at a hemophilia treatment center confirmed her diagnosis.
What you can do
If hemophilia runs in your family, bring these questions to your next appointment:
What are my factor VIII or IX levels, measured when I was well and not pregnant?
What's my ferritin, and what are we aiming for?
What's my plan for heavy periods?
Should my joints be checked?
Who else in my family should be tested?
You are allowed to ask every one of them. And if you're not being heard, you're allowed to find someone who will listen. Find a provider who gets it.
This page summarizes published research and isn't medical advice. Talk with your hematologist or hemophilia treatment center about your own care.
Read the full paper: Lavin M, Abdul-Kadir R, Sidonio RF. How I treat bleeding in women and girls with hemophilia/hemophilia carriers. Blood. 2026. [Download the PDF] Shared with permission of the authors.
