From the Guidelines
For a 28-year-old requesting Depo-Provera, this is an appropriate contraceptive option, with the standard regimen being 150 mg administered as an intramuscular injection every 12 weeks (3 months) 1.
Key Considerations
- The first injection should ideally be given within the first 5 days of the menstrual cycle to ensure immediate contraceptive protection, but it can be initiated on the same day as the visit (“mid-cycle” or “quick” start) as long as the healthcare provider is reasonably certain the patient is not pregnant 1.
- Before administration, pregnancy should be ruled out, and a medical history should be taken to identify any contraindications such as breast cancer, unexplained vaginal bleeding, liver disease, or risk factors for osteoporosis.
- Common side effects include irregular bleeding, weight gain, headaches, and mood changes, with weight gain being a significant concern as studies suggest it can be a strong predictor of future excessive weight gain with ongoing DMPA use 1.
Counseling and Recommendations
- Patients should be counseled that a backup method (e.g., condoms or abstinence) should be used for at least the first week for contraceptive efficacy and that a condom should be used at all times for protection against STIs 1.
- Long-term use (beyond 2 years) may be associated with decreased bone mineral density, which is generally reversible after discontinuation, but patients should be advised on measures that promote skeletal health, such as daily intake of 1300 mg of calcium and 600 IU of vitamin D and regular weight-bearing exercise 1.
- Return to fertility may be delayed for 6-12 months after the last injection, and Depo-Provera does not protect against sexually transmitted infections, so condom use should be recommended if STI protection is needed.
Follow-Up
- The patient should be advised to return in exactly 12 weeks for their next injection to maintain contraceptive effectiveness, with visits scheduled every 11 to 12 weeks to allow for missed or delayed visits 1.
From the FDA Drug Label
Medroxyprogesterone Acetate Injectable Suspension, USP is indicated only for the prevention of pregnancy The effectiveness of Medroxyprogesterone Acetate Injectable Suspension, USP is dependent on the patient returning every 3 months (13 weeks) for reinjection
- Indication: Medroxyprogesterone acetate (IM) is indicated for the prevention of pregnancy.
- Administration: It is a long-term injectable contraceptive in women when administered at 3-month (13-week) intervals.
- Effectiveness: The 12-month failure rate for the group of women treated with Medroxyprogesterone Acetate Injectable Suspension, USP was zero (no pregnancies reported) to 0.7 by Life-Table method 2. The patient can be given the Depo shot as it is indicated for the prevention of pregnancy.
From the Research
Potential Side Effects of Depo Shot
- Weight gain, increased body fat mass, irregular bleeding, and amenorrhea are associated with DMPA use, as suggested by studies of moderate or high risk of bias 3
- Inconsistent evidence exists for an association between DMPA use and mood or libido changes 3
- Limited evidence exists for an association between DMPA use and decreased risk of cancers and tubal infertility 3
Risk of Venous Thrombosis
- Injectable depot-medroxyprogesterone acetate contraceptives are associated with a 3.6-fold increased risk of venous thrombosis compared with nonusers of hormonal contraceptives 4
- The use of a levonorgestrel intrauterine device is not associated with an increased risk of venous thrombosis 4
- Current use of higher-dose progestogens, such as DMPA, is significantly associated with increased odds of VTE compared with nonuse 5
Adverse Events Associated with Medroxyprogesterone Acetate
- Significant adverse events associated with MPA include unintended pregnancy, bone pain, gait disturbance, dental caries, decrease in blood pressure, and osteonecrosis 6
- These adverse events were identified through a pharmacovigilance analysis using FDA adverse event reporting system data 6