The effects of subcutaneous depo-medroxyprogesterone acetate (DMPA-SC) injection on androgenic markers in obese women have not previously been studied.Five normal-weight [body mass index (BMI)=18.5-24.9 kg/m²], five obese (BMI=30-39.9 kg/m²) and five extremely obese (BMI≥40 kg/m²) women were recruited for this prospective experimental study in which 104 mg DMPA-SC was administered at baseline and 12 weeks later. Serum levels of total testosterone (T), androstenedione (A), dehydroepiandrosterone sulfate (DHEAS), 3α-androstanediol glucuronide and sex hormone-binding globulin (SHBG) were quantified by immunoassay methods at baseline and at 13 and 26 weeks following the first injection; free T was calculated.At baseline, obese women had lower levels of A and SHBG and higher total and free T levels than normal-weight women. There were a statistically significant decrease in the levels from baseline to week 26 among all three BMI classes for A, total T and SHBG (p≤.03) and an increase from baseline to week 26 in weight (p=.02). In addition, there was a statistically significant decrease in DHEAS from baseline to week 13 among all three BMI classes (p=.01), which was not sustained at week 26 (p>.1). Overall, the three groups responded similarly to all changes at week 13, and there were no statistically significant differences between groups at any time point (p≥.06).DMPA-SC use in normal-weight, obese and extremely obese women can decrease serum androgen markers.