abnormal uterine bleeding
"This is my third time using the depo, in between children. After reading comments I thought I'd share. When  I have my first shot I bleed continuously with cramps and I suffer migraines for a couple of months but then after the second or third it stops altogether with occasional spotting. Now for me whose normal periods are extremely heavy for four days, with cramps, back ache and migraines lasting longer I know it's worth the two months of a normal bleed for however long I'm on the depo for with just spotting. 

It's just a matter of waiting it out for the effects to start. I haven't had a migraine in over a month, I've spotted once, I've had no cramps for two. This time round I'm just coming up to my fourth shot"