Levonorgestrel
"I'm 24, previously taking oral contraceptives for 9 years. I'm giving this 5 because it is effective in the most basic sense. I no longer worry about getting pregnant or taking pills and my periods are regular and very light. However I am one year in and planning to get it removed because of the side effects. First, the insertion was incredibly painful for me followed by excruciating cramps. The first 6 months was radical mood swings, acne, weight gain and cramping that gradually stabilized. I'm a year in now though and I'm finding it hard to work off the weight, I'm still very emotional, my skin is bad (possibly unrelated but my eczema has come back), low sex drive. I gave it a chance but I'd rather take pills/use condoms and be happy."