Do you need another form of contraception with Imdepo (Depot Medroxyprogesterone Acetate, DMPA)?

Do You Need Another Form of Contraception with Depo (DMPA)?

No, you do not need another form of contraception with Depo-Provera (DMPA) once it becomes effective, which occurs 7 days after the first injection if given outside the recommended timing window. 1

Timing and Backup Contraception Requirements

First Injection - No Backup Needed If:

• Given during the first 5 days of a normal menstrual period 2
• Given within the first 5 days postpartum 2
• Given immediately post-abortion (surgical or medical) 1

In these scenarios, DMPA is immediately effective and no additional contraception is required. 1

First Injection - 7 Days Backup Required If:

• Given more than 7 days after menstrual bleeding started 1
• Given ≥21 days postpartum (if menstrual cycles have not returned) 1
• Given at any time when you cannot be reasonably certain the woman is not pregnant 1

You must abstain from intercourse or use additional contraceptive protection for 7 days after the injection in these circumstances. 1

Switching from Other Methods

When switching from another contraceptive method to DMPA:

• The injection can be given immediately if reasonably certain the woman is not pregnant 1
• If it has been >7 days since menstrual bleeding started, use backup contraception for 7 days 1
• When switching from oral contraceptives, give DMPA on the day after the last active tablet (or latest, the day following the final inactive tablet) for continuous coverage 2

Special Consideration - Switching from IUD:

If the woman has had intercourse since her current menstrual cycle started AND it's been >5 days since bleeding started, consider one of these options 1:

• Retain the IUD for at least 7 days after DMPA injection, then remove
• Abstain or use barrier contraception for 7 days before IUD removal
• Use emergency contraception at the time of IUD removal

Ongoing Use - No Additional Contraception Needed

Once established on DMPA:

• No backup contraception is required between properly timed injections 1
• DMPA has a failure rate of less than 1% with perfect use and 3% with typical use 1
• The method is highly effective because it works through multiple mechanisms: inhibiting ovulation, thickening cervical mucus, and causing endometrial atrophy 3

Reinjection Timing:

• Standard schedule is every 3 months (13 weeks) 2
• If the interval between injections is >13 weeks, determine the patient is not pregnant before administering the next dose 2
• If reinjection is delayed, use backup contraception for 7 days after the late injection 1

Important Clinical Caveats

DMPA does NOT protect against sexually transmitted infections - condoms should be used for STI prevention regardless of DMPA use. 1

The evidence from CDC guidelines demonstrates that when DMPA is administered on days 1-7 of the menstrual cycle, it reliably inhibits ovulation; when given after day 7, ovulation may occur in some women, hence the 7-day backup requirement. 1 Studies show that cervical mucus becomes unfavorable for sperm penetration within 24 hours of injection, providing rapid contraceptive effect. 1

Common pitfall: Providers sometimes unnecessarily delay DMPA initiation waiting for the next menstrual period. The CDC explicitly states this is unnecessary - DMPA can be started at any time if pregnancy can be reasonably excluded, with appropriate backup contraception used when indicated. 1

Serum MPA levels plateau at approximately 1.0 ng/mL for about 3 months after a 150 mg injection, maintaining contraceptive efficacy throughout this period. 3 Some women may have detectable MPA for up to 9 months after a single injection, though contraceptive efficacy is only guaranteed for the 13-week dosing interval. 3