A study suggests that people with type AB and women with B may be a little more likely to suffer one than people with O blood, the most common type.
This is based on observing 90,000 people in two health studies that have gone on for more than 20 years. Doctors say this doesn't prove a link, but other research ties blood type to the risk of bleeding, heart attacks and blood clots in the legs.
Doctors suggest that people worried about being at higher risk might want to keep their blood pressure and cholesterol in line.
The study was discussed Wednesday at an American Heart Association conference.