risk of clots with HBC?

[andyrea.livejournal.com]

What hormone in birth control is responsible for the increased risk of blood clots with HBC? Is it the estrogen, progestin, or a mix of both? What is the reasoning behind this? thanks!

Comments

[x-cupkake.livejournal.com]

It was Estrogen that caused my migraines and the doctor said it could cause a stroke...so maybe it's that?
(Sorry if I'm no help)

[queensugar.livejournal.com]

It's primarily the estrogen, though in combination with certain newer progestins, that appears to increase the risk. (I.E. combination pills with newer progestins appear to have a higher clot risk than older progestins.) Basically, estrogen leads to high blood pressure, and high blood pressure raises the risk of blood clots (regardless of what's causing the high blood pressure).