Many women, and even many clinicians, believe that taking combination oral contraceptives (i.e., contraceptives that contain 2 ingredients, estrogen and progestin) will cause weight gain. Such a perception often leads to a significant number of women (especially younger ones) being reluctant to use this highly effective method of contraception, and also causes many women who are already using this method to discontinue it and switch to another method in the process. However, is there indeed a link between the use of compounded oral contraceptives and weight gain? In 2014, Gallo and other experts conducted a study on the topic of whether compounded oral contraceptives have an effect on body weight. They searched all studies on combination oral contraceptives in repositories such as CENTRAL, MEDLINE, POPLINE, EMBASE, LILACS, Clinicaltrial.com, and ICTRP through November 2013, and also contacted known investigators and pharmaceutical companies for unretrieved published and unpublished information and data from clinical trials. The results found that most comparisons between different combination oral contraceptives did not show substantial weight changes. In addition, no differences in oral contraceptive discontinuation due to weight change were observed between groups, i.e., no increase in women discontinuing the combination contraceptive or the combination patch due to weight change was observed. Based on these findings, Gallo et al. concluded that although the available evidence is not sufficient to determine that the combination oral contraceptive pill has no effect on body weight at all, it is certain that the evidence for a modest effect of the combination oral contraceptive pill on body weight is still sufficient. Clinical trials evaluating the relationship between compounded oral contraceptives and changes in body weight require a control group of placebo or non-hormonal contraceptive methods to control for other factors that affect body weight, such as the effect of time on body weight.