Body weight and body composition of depot medroxyprogesterone acetate users.

OBJECTIVES: Weight gain is a concern with the contraceptive depot-medroxyprogesterone acetate (DMPA); however, this issue remains controversial. The objective of this study was to compare body weight (BW) and body composition (BC) in DMPA and copper intrauterine device (IUD) users at baseline and after one year of use.

STUDY DESIGN: We enrolled new DMPA users and age and weight matched new IUD users into this prospective study. Weight and height were measured, BC (fat and lean mass) was evaluated using dual-energy X-ray absorptiometry, and physical activity was assessed at baseline and at 12 months. Student's paired t test and the Wilcoxon paired test for matched samples were used.

RESULTS: Ninety-seven women were enrolled for the study; 26 matched pairs continued using the initial method for at least one year, and completed the baseline and 12 month assessments. An increase of 1.9 kg occurred in BW (p=.02) in DMPA users at 12 months of use, resulting from an increase in fat mass of 1.6 kg (p=.03). Weight remained stable in IUD users; however, there was an increase in lean mass at 12 months of use (p=.001). The number of women practicing physical activity increased in this group. There was a significant difference between the groups regarding the variation in the percentage of central fat (p=.04).

CONCLUSION: Weight gain in the DMPA group after the first year of use resulted from an increase in fat mass. Weight remained stable in the IUD group; however, an increase in lean mass and a reduction in localized abdominal fat mass occurred, possibly because more users were practicing physical activity.

IMPLICATIONS STATEMENT: There was a greater increase in body weight in DMPA users compared to TCu380A IUD users in the first year of use of the contraceptive method. Furthermore, the weight increase in users of DMPA occurred principally as the result of an increase in fat mass. Physical activity probably could increase the lean mass in the users of TCu380A IUD.