Is the Depo (Depot Medroxyprogesterone Acetate, DMPA) shot a suitable contraceptive option for teenagers?

Depo-Provera for Teenagers: Clinical Recommendation

The Depo-Provera (DMPA) shot is a suitable and highly effective contraceptive option for teenagers, with typical-use failure rates of approximately 6% in the first year, and should not be withheld due to bone density concerns, as bone mineral density substantially recovers after discontinuation. 1, 2

Efficacy and Administration

DMPA is highly effective contraception for adolescents, with two equivalent formulations available: 150 mg intramuscularly or 104 mg subcutaneously, administered every 13 weeks (up to 15 weeks). 1, 3 Many providers schedule adolescent visits every 11-12 weeks to allow buffer time for missed appointments. 1, 3

• "Quick start" or "mid-cycle" initiation is acceptable if the provider is reasonably certain the adolescent is not pregnant. 1, 3
• Backup contraception (condoms or abstinence) must be used for the first 7 days after initial injection for contraceptive efficacy. 1, 3
• Condoms should be used at all times for STI protection, as DMPA provides no protection against sexually transmitted infections. 1, 3

Critical Counseling: Menstrual Changes

Pre-injection counseling about menstrual irregularities is essential and significantly reduces discontinuation rates. 1, 3 Nearly all patients experience unpredictable spotting and bleeding initially, but these irregularities typically improve over time, with amenorrhea becoming common with continued use. 1, 3

This is the most common reason for discontinuation in adolescents, making upfront counseling critical to method continuation. 1

Bone Mineral Density: The Key Controversy

The FDA black-box warning about bone mineral density loss should not prevent prescribing DMPA to adolescents or limit use to 2 years. 1, 4, 5 Here's why:

Evidence on BMD Loss in Adolescents:

• Adolescents using DMPA experience significant BMD declines: -6.4% at total hip and -5.4% at femoral neck after 4.6 years of use. 2
• The decline is most pronounced in the first two years, with smaller declines in subsequent years. 2
• New users lose bone density more rapidly than prevalent users. 6

Evidence on BMD Recovery:

• BMD substantially recovers after DMPA discontinuation, with significant gains at all anatomical sites. 1, 2, 6
• Adolescents who discontinued DMPA experienced annualized BMD increases of 1.34% at hip, 2.86% at spine, and 3.56% at whole body compared to nonusers. 6
• However, adolescents treated for more than 2 years did not fully recover baseline BMD at femoral neck and total hip even up to 60 months post-treatment. 2
• Lumbar spine BMD recovered to baseline levels after discontinuation, regardless of treatment duration. 2

Clinical Interpretation:

The American College of Obstetricians and Gynecologists (ACOG) does not advise limiting DMPA use to 2 years, recognizing that the risk of unwanted pregnancy if contraceptive options are limited outweighs the bone density concerns. 1, 4, 5 No high-quality data demonstrate that DMPA affects fracture risk in adolescents or adults later in life. 5

Weight Gain Considerations

Weight gain occurs in some but not all patients. 1 The critical predictor is early weight gain status at 6 months—those who gain more than 5% of body weight at 6 months are at high risk for excessive future weight gain. 1, 3

This provides a practical decision point: reassess at 6 months and discuss alternative methods if significant early weight gain occurs. 1

Skeletal Health Promotion

All adolescent DMPA users should receive counseling on skeletal health measures: 1, 3

• Daily intake of 1300 mg calcium and 600 IU vitamin D
• Regular weight-bearing exercise
• Avoidance of smoking and alcohol

Routine bone density monitoring is not recommended, as there is no evidence to support this practice. 1, 3

Special Populations

HIV-Infected Adolescents:

• DMPA has no significant interactions with antiretroviral agents (including efavirenz, zidovudine, lamivudine, nevirapine, and nelfinavir). 1, 3
• HIV-infected women should be informed that DMPA may or may not increase HIV transmission risk to partners and should continue condom use for HIV prevention. 1, 3

Other Medical Conditions:

DMPA is particularly useful for adolescents with: 1

• Medical conditions requiring long-term menstrual suppression where estrogen is contraindicated
• Disabled nonambulatory adolescents (avoids estrogen exposure and provides menstrual suppression)
• Bariatric surgery patients (who need to delay pregnancy 12-18 months but experience rapid return to fertility)

Common Pitfalls to Avoid

1. Do not fail to counsel about menstrual irregularities before the first injection—this is the single most important factor in method continuation. 1, 3

2. Do not limit DMPA use to 2 years based solely on BMD concerns—the benefits of pregnancy prevention outweigh the risks. 1, 4, 5

3. Do not routinely monitor bone density—there is no evidence to support this practice. 1, 3

4. Do not assume amenorrhea after DMPA is pathologic without ruling out other causes, as amenorrhea is an expected outcome with continued use. 3

5. Do not overlook the 6-month weight assessment—this is the critical decision point for identifying adolescents at risk for excessive weight gain. 1, 3

Comparison to Other Methods

While long-acting reversible contraceptives (LARCs) like IUDs and implants have higher efficacy and continuation rates (failure rates of 0.05-0.8% vs 6% for DMPA), 1 DMPA remains an excellent option for adolescents who prefer injectable contraception, particularly those with contraindications to estrogen or who need convenient, private contraception. 1

The key is thorough pre-injection counseling about menstrual changes, weight monitoring at 6 months, and skeletal health promotion, while avoiding unnecessary restrictions on duration of use. 1, 3