"i&#039;m 27 w/ two kids. after my second child was born in 2008 i suffered from almost daily tension/migraine headaches. i wanted to try mirena as a solution to birth control and possibly help my headaches. after 4 months my headaches are slightly better but i have had some noticeable side effects; 10-15 lbs weight gain, increased discharge, longer periods, and cramping after sex or exercise. "