Switching from Oral Contraception to Depo-Provera
Start Depo-Provera the day after the last active oral contraceptive pill, or at the latest, on the day following the final inactive tablet, to ensure continuous contraceptive coverage. 1
Timing of the Switch
The FDA-approved labeling explicitly states that when switching from oral contraceptives, the first Depo-Provera injection should be administered on the day after the last active tablet or at the latest on the day following the final inactive tablet. 1
This timing ensures continuous contraceptive coverage based on the mechanism of action of both methods, preventing any gap in pregnancy protection. 1
No backup contraception is required when following this timing, as the oral contraceptive provides coverage through the transition period. 1
Dosing and Administration Details
Administer 150 mg of medroxyprogesterone acetate by deep intramuscular injection in the gluteal or deltoid muscle using strict aseptic technique. 1
Alternatively, 104 mg subcutaneous DMPA can be used, which has equivalent effectiveness and side effects to the 150 mg intramuscular formulation. 2
Vigorously shake the vial just before use to ensure uniform suspension. 1
Assess body habitus prior to injection to determine if a longer needle is necessary, particularly for gluteal injections, to avoid inadvertent subcutaneous administration. 1
Repeat Injection Schedule
The injection can be given up to 2 weeks late (15 weeks from the last injection) without requiring additional contraceptive protection. 3
Many providers schedule patients every 11-12 weeks to allow buffer time for missed appointments. 2
Critical Pre-Injection Counseling
Menstrual Changes
Nearly all patients experience menstrual irregularities initially with unpredictable spotting and bleeding. 2
Bleeding patterns typically improve over time, with amenorrhea becoming common with continued use (often by 12 months). 2
Pre-injection counseling about menstrual changes reduces discontinuation rates. 2
For spotting or light bleeding, NSAIDs for 5-7 days may be considered. 3
Weight Gain
Weight gain occurs in some but not all patients. 2
A significant predictor of future excessive weight gain is weight gain status at 6 months (>5% body weight increase). 2
Return to Fertility
- Return to fertility may be delayed for 9-18 months after discontinuation, which is a critical difference from oral contraceptives that allow immediate return to fertility. 3
Bone Mineral Density
DMPA causes reversible reductions in bone mineral density, but BMD substantially recovers after discontinuation. 2
The American College of Obstetricians and Gynecologists does not recommend limiting use to 2 years despite the FDA black-box warning, as the benefits of pregnancy prevention generally outweigh the risks. 3
For patients using DMPA beyond 2 years, counsel about measures to promote skeletal health: daily intake of 1300 mg calcium and 600 IU vitamin D, regular weight-bearing exercise, and smoking cessation. 3
Contraindications to Screen For
Before switching from oral contraceptives to Depo-Provera, verify the patient does not have: 1
- Active thrombophlebitis, current or history of thromboembolic disorders, or cerebral vascular disease
- Known or suspected breast malignancy
- Known hypersensitivity to medroxyprogesterone acetate
- Significant liver disease
- Undiagnosed vaginal bleeding
Common Pitfalls to Avoid
Do not wait for a menstrual period to start Depo-Provera when switching from oral contraceptives—this creates an unnecessary gap in contraceptive coverage and increases pregnancy risk. 1
Do not fail to counsel about menstrual irregularities before the first injection, as this significantly reduces discontinuation. 2
Do not assume amenorrhea after DMPA is pathologic without ruling out other causes. 2
Do not routinely monitor bone density or limit use to 2 years based solely on BMD concerns. 2