I've lost 20 lbs in 11 months.i started a new pill with a high estrogen content 6 months ago.i get breakthrough week 2 like clockwork. why?

Hormones: Hormones are the usual cause a breakthrough bleeding really can be pregnancy or infection. See family doctor OB/GYN for evaluation and specific diagnosis and treatment

Many Possibilities: First, why the high estrogen pill? If you have a fibroid it could increase its size which could cause increased bleeding. Estrogen without appropriate progesterone also increases the uterine lining thickness and can cause bleeding. If you have a thyroid disorder estrogen also increases your thyroxine requirement and could cause abnormal bleeding. There are many more, need more info and eval!