I have been on Yasmin for 3 months. During the first month I had mood swings and felt very fatigued. During the second and third months I've had severe muscle cramps in my legs, on and off backache, more fatigue, and shoulder cramps. I am on it to regulate my period which before could happen three weeks apart, or six months apart. I am beginning to feel as though these side effects aren't worth it just to have a regular period.