The DepoProvera injection is effective within 24 hours after the first injection. If your unprotected intercourse was at least 24 hours after your first injection, then pregnancy is very unlikely.
The Depo injection is effective for up to 13 weeks. If you are late for your injection, it is best to use a back up method like condoms or abstinence. It is important to continue your injections on time to maintain your birth control.
31. January 2012
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