"i used mirena for 11 months for birth control. i am very sensitive so the insertion was painful (lots of cramping and spotting after).  i would then (for the first 3 months or so) get random, painful cramps. i also instantly gained 5 lbs and 10 lbs over this past year in total.  apart from the hair thinning (which i am unsure was from the mirena) i got really bad acne on my chin area and on my back. i was hoping that would change bc aside from that, i got no periods at all and it was very effective in preventing pregnancy. i just got mine out today and taking it out was a cinch.  i&#039;m hoping my body will regulate itself quickly."