When you get birth control like an implant , IUD , pill , patch , shot , or ring – they don’t take effect immediately
If you’re taking your birth control according to instructions:
IUD, Pill, Patch & Ring: Expect up to 7 days before an IUD, the Pill or a Patch to be effective, use a backup method like condoms for those 7 days. A hormonal IUD if inserted 7 days before the start of your period, is immediately effective.
Depo-Provera: Starts working within 24 hours of the first shot if it’s injected within 5 days of beginning of your period.