Assessing the Impact of Contraceptives on Bone Health Using 41Ca

• Status: Active, not recruiting
• Trial end date: 2022-12-01
• Target enrollment: 0
• Participant gender: Female

Summary

This preclinical randomized crossover study will examine the effects of oral versus non-oral contraceptive therapy on bone turnover in young exercising women. In an effort to expose the route-dependent effects of oral versus non-oral contraceptive therapy on bone turnover, the investigators will examine 1) the effects of ethinyl estradiol on bone calcium balance using the 41Ca technology and 2) the underlying physiological mechanisms associated with the effects of oral versus non-oral contraceptive therapy on net bone calcium balance.

• Phase: Phase 4
• Accepts Healthy Volunteers?: Accepts Healthy Volunteers

Details

• Lead Sponsor: Penn State University
• Collaborator: Purdue University
• Treatments: Contraceptive Agents; Contraceptives, Oral; Contraceptives, Oral, Combined; Ethinyl Estradiol; NuvaRing

Criteria

Inclusion Criteria:

1. Female

2. Age 18-25 yrs

3. BMI 18-29 kg/m2

4. Non-smoking

5. Willing to refrain from using hormonal contraceptives for the equilibration + baseline period of the study (~150 days)

6. Availability to frequently visit the laboratory in the next 12 months

7. Not currently pregnant nor intending to become pregnant in the next 12 months

8. Not lactating

9. No apparent metabolic, endocrine, musculoskeletal, or severe psychiatric disease

10. Willing to maintain consistent exercise (aerobic, weight-bearing) and dietary habits during pre-intervention and intervention periods

11. Willing to refrain from supplements other than those provided by study staff in the next 12 months

12. Variable physical activity acceptable, but mode must be primarily weight bearing

13. At least 9 menses in the past 12 months

Exclusion Criteria:

1. Non-weight bearing exercise as primary mode of physical activity

2. Resistance exercise training (≥ 2 times 30 minutes per week of resistance exercise)

3. Complete seasonal change of impact mode of physical activity

4. Known or suspected metabolic or endocrine disease

5. Smoking

6. Pregnant

7. Currently consuming large amounts of soy products

8. Current clinical eating disorder or other axis 1 psychiatric disorder or bipolar disorders

9. Oral or hormonal contraceptive use in the last 6 months

10. Hyperparathyroidism

11. Liver or renal disease

12. Evidence of malabsorption or skeletal disorder

13. Thyroid abnormalities (controlled hypothyroidism acceptable)

14. Chronic use of non-steroidal anti-inflammatory drugs (NSAIDS)

15. Taking medications known to have interactions with oral or vaginal contraceptive therapy

16. Other Exclusion Criteria proposed by the World Health Organization COC Contraindications (Grossman et al., 2011).