[Variation of weigth among users of the contraceptive with depot-medroxyprogesterone acetate according to body mass index in a six-year follow-up].

PURPOSE: To determine weight variation in women with different Body Mass Index (BMI) in use of trimestral injections of depot-medroxyprogesterone acetate (DMPA), and compare it to women users of a non-hormonal method.
METHODS: Retrospective study with the chart review of 226 DMPA users and 603 controls, users of DIU TCu380A. Women were distributed in categories, according to their initial BMI, as having normal weight (<25 kg/m(2)), overweight (25 to 29,9 kg/m(2)) and being obese (>or=30 kg/m(2)), and were followed-up for six years, with yearly measurements of weight and BMI. The statistic test ANOVA was used to measure the weight variation among the groups in each BMI category every year.
RESULTS: The average age at the onset of the method employed was higher in the study group than in the controls, in all the BMI categories: 31.6+/-SD 7.1 X 27.4+/-SD 5.5 in the normal weight category (p<0.0001); 37.3+/-SD 6.8 X 29.2+/-SD 6.0 in the overweight category (p<0.0001); and 35.3+/-SD 6.4 X 29.7+/-SD 5.8 among obese women (p<0.0001). DMPA users showed weight increase as compared to the controls in the overweight category (p=0.0082); and the weight increase along the observation period was also higher among the DMPA users than among the controls, for the normal weight (p<0.0001) and overweight (p=0.0008) categories. In the obese group, there was no BMI variation between the groups, nor along the period during which they were using the method.
CONCLUSIONS: There was no change in weight gain among DMPA users from the obese category. Prospective studies should be done with metabolic tests to establish the determining factors of weight gain in normal and overweight women.