Weight gain in obese and nonobese adolescent girls initiating depot medroxyprogesterone, oral contraceptive pills, or no hormonal contraceptive method.

OBJECTIVE: To examine weight changes in a large cohort of obese and nonobese adolescent girls initiating depot medroxyprogesterone acetate (DMPA), an oral contraceptive (OC), or no hormonal contraceptive method (control). DESIGN, SETTING, AND PARTICIPANTS: Prospective study of 450 adolescent girls, aged 12 to 18 years, who attended 4 urban health clinics and selected DMPA, OC, or control. Data collection occurred at baseline and at 6, 12, and 18 months; consisted of structured interview and measurement of height and weight; and occurred from April 19, 2000, through September 26, 2003. MAIN OUTCOME MEASURE: Weight was examined as mean change over 18 months and actual weight at each study visit. On the basis of preliminary analyses, we stratified the sample according to baseline obesity status (nonobese, body mass index [calculated as weight in kilograms divided by the square of height in meters] < 30; obese, body mass index > or =30). RESULTS: Adolescent girls who were obese at initiation of DMPA gained significantly more weight than did obese girls starting OC or control (P<.001 for both). At 18 months, mean weight gain was 9.4, 0.2, and 3.1 kg for obese girls receiving DMPA, receiving OC, and control, respectively. Weight gain in obese girls receiving DMPA was also greater than weight gain in all nonobese categories (4.0 kg, DMPA; 2.8 kg, OC; 3.5 kg, control; P<.001). A significant interaction (P = .006) between length of time receiving DMPA and weight gain was evident for obese subjects. CONCLUSIONS: Over 18 months, DMPA use was associated with increasing rates of weight gain in obese subjects. The potential contribution to severe obesity in this population is concerning.

Reference values for bone mineral density in 12- to 18-year-old girls categorized by weight, race, and age.

BACKGROUND: Normative bone mineral density (BMD) values for adults do not apply to the pediatric population because of dramatic and variable rates of bone mineral acquisition that take place throughout adolescence. OBJECTIVE: This study was designed to provide normative BMD values for the lumbar spine and femoral neck by age, weight, and race in female adolescents for use by clinicians. MATERIALS AND METHODS: The study population comprised 422 healthy adolescent girls aged 12-18 years recruited from four primary-care clinics. BMD measurements were performed with dual-energy X-ray absorptiometry (DEXA). RESULTS: The major statistical predictors of lumbar spine BMD and femoral neck BMD were race, chronological age, and weight. There was an increase in both lumbar spine and femoral neck BMD that paralleled an increase in age and weight. In addition, the lumbar spine BMD and the femoral neck BMD were higher in the black participants than in the non-black participants with mean BMD values in grams per centimeter squared of 1.02 and 0.98, respectively, for blacks and 0.96 and 0.89, respectively, for non-blacks ( P<0.001). CONCLUSION: Our study produced the largest set of lumbar spine and femoral neck BMD normative values for female adolescents and confirms the importance of both demographic and anthropomorphic variables in determining normative BMD values.