Norethindrone
birth control
"After an episode of erythema nodesum from my last birth control pills, my doctor suggested I try a 3 month course of Micronor to see how my body would react to the progesterone.  Well, I've gained 5lbs and had my period or spotting 27 out of the 42 days I've been taking it. 

My doctor wants me to continue on it to prepare for an IUD, but honestly I don't want it if the breakthrough is going to be this problematic."