A Cochrane review «»1 «Lopez LM, Edelman A, Chen-Mok M et al. Progestin-o...»1 included 22 studies with a total of 11 450 subjects. 17 of the studies were non-randomized and 5 RCTs. Two studies examined progestin-only pills (POPs), 4 the levonorgestrel-releasing intrauterine system (LNG-IUS), 5 trials progestin implants, and 16 trials depot medroxyprogesterone acetate (DMPA). Comparison groups were similar for weight change in 15 studies. 8 studies were rated as high or moderate quality; in only one of them there was a slight difference in weight. Mean gain was less than 2 kg for most studies up to 12 months, and usually similar for the comparison group using another contraceptive.