"i&#039;m 24 years old and i would have to say mirena is the most effective birth control. but with that, of course there are some side effects. i&#039;ve gained about 30lbs, very heavy mood swings, i break out more than i normally do and i&#039;m always hungry. i&#039;ve had it for a year....my partner loves it, no complaints from his end. it is very convenient...the insertion was painful but after a month it was fine. i get a light 2-3 day period every 3 months which is great!"