What is the recommended contraceptive regimen for a female patient of reproductive age with no known contraindications, considering Depo-Provera (medroxyprogesterone acetate) as an option?

Depo-Provera Prescription for Contraception

Prescribe Depo-Provera (medroxyprogesterone acetate) 150 mg intramuscularly every 13 weeks (or 104 mg subcutaneously every 13 weeks) for highly effective contraception with a failure rate of 0.3% in typical use. 1, 2, 3

Pre-Prescription Requirements

No examination or laboratory testing is required before initiating Depo-Provera. 4 Specifically:

• Blood pressure measurement: not required 4
• Pelvic examination: not required 4
• Weight/BMI, glucose, lipids, liver enzymes: not required 4
• Clinical breast examination: not required 4

The only requirement is reasonable certainty that the patient is not pregnant before the first injection. 1, 4

Prescription Details

Medroxyprogesterone Acetate Injectable Suspension 150 mg intramuscularly every 13 weeks (91 days)

• Administer by deep intramuscular injection into the gluteal or deltoid muscle 3, 5
• Alternative: 104 mg subcutaneously every 13 weeks 2
• Can be given up to 2 weeks late (15 weeks total) without requiring backup contraception 2
• Dosage does not need adjustment for body weight 3

Timing of First Injection

The first injection can be given at any time if reasonably certain the patient is not pregnant. 1, 4

• If started within 7 days of menses onset: No backup contraception needed 1
• If started >7 days after menses: Abstain from intercourse or use barrier methods for 7 days 1, 4

Absolute Contraindications

Do not prescribe if the patient has: 4

• Active arterial thromboembolic disease (stroke, MI) or history thereof
• Known liver impairment or active liver disease
• Undiagnosed vaginal bleeding 3
• Known or suspected breast malignancy 3
• Known or suspected pregnancy 3

Essential Patient Counseling

Menstrual Changes (Most Common Side Effect)

Nearly all patients will experience menstrual irregularities initially, including irregular bleeding, spotting, or heavy bleeding. 2 Counsel that:

• 57% of women develop amenorrhea by 12 months of use 5
• Pre-injection counseling about menstrual changes significantly improves continuation rates 2
• Menstrual changes are not medically harmful 2

Bone Mineral Density Concerns

All patients must receive counseling on skeletal health measures: 2

• Increase calcium intake
• Ensure adequate vitamin D intake
• Engage in regular weight-bearing exercise
• Smoking cessation

The American College of Obstetricians and Gynecologists does not recommend limiting use to 2 years, but bone mineral density should be evaluated when long-term use is needed, and the method should only be used long-term if other methods are inadequate. 2

Weight Gain

Weight gain is common, with 21% of adolescents experiencing early weight gain that continues over 18 months. 2 Counsel patients about this possibility upfront.

Delayed Return to Fertility

MPA can be detected in serum for up to 9 months after a single injection, and return to fertility is delayed for several months after discontinuation. 6 This is a temporary effect, not permanent infertility.

Clinical Advantages to Emphasize

Depo-Provera is one of the most effective reversible contraceptives available, with a perfect use failure rate of 0.2%. 2, 3 Additional benefits include:

• Does not contain estrogen, making it suitable for women with contraindications to estrogen (history of thromboembolism, migraine with aura, cardiovascular disease) 2
• Convenient quarterly administration rather than daily pill-taking 2
• Improves dysmenorrhea and protects against iron-deficiency anemia through reduced menstrual bleeding 2
• Reduces risk of endometrial cancer with prolonged use 2
• May raise seizure threshold in epileptic patients and decrease sickle cell crises 2
• Safe for breastfeeding women ≥1 month postpartum 2

Special Populations

Depo-Provera is particularly appropriate for: 1, 2

• Women with antiphospholipid antibody positivity (avoid combined estrogen-progestin contraceptives) 1
• Women with systemic lupus erythematosus with moderate-to-high disease activity 1, 2
• Women on long-term rifampin therapy (effectiveness not reduced, unlike combined oral contraceptives) 2
• Breastfeeding women 2

Avoid Depo-Provera in patients at risk for osteoporosis (e.g., prolonged corticosteroid use, eating disorders, family history of osteoporosis). 1

Drug Interactions

Certain medications can reduce Depo-Provera's contraceptive efficacy: 4

• Anticonvulsants: phenytoin, carbamazepine, barbiturates, primidone, topiramate, oxcarbazepine
• Rifampin or rifabutin

Consider alternative contraception or additional backup methods if these medications are necessary.

Follow-Up Schedule

Schedule return visits every 13 weeks (91 days) for repeat injections. 3 The effectiveness of Depo-Provera is dependent on the patient returning on schedule. 3 Patients have a 2-week grace period (up to 15 weeks total) without requiring backup contraception. 2