"i have been on yaz for a couple months. i decided to switch to yaz to gain weight and clear up my mild acne. overall i have had a positive experience with it. in the beginning, my periods lasted only a couple days, but now, i have no period at all. also, my face is clear, but i did not gain weight from the pill. the weight i have gained was from muscle weight from working out. i&#039;d say the only negative were my massive headaches when i did have my period. the headaches would come on my first day of my period. but now, with no period, i have no headache!"