If you need your birth control to take effect right away, that’s an important concern to discuss with your doctor. Different methods vary in terms of timing.
Barrier methods like condoms work immediately, whereas a vasectomy may take three months or more. Timing for pill types depends on whether it's a combination or progestin-only pill and your menstrual cycle phase. You can start both pill types anytime, but backup methods like condoms may be needed for the first seven days.
For combination pills (COCs): If you begin within five days of your period onset, you're immediately protected from pregnancy without requiring a backup birth control method. For instance, if your period begins on a Wednesday morning, you can start the pill up to the subsequent Monday morning for immediate protection. If you start at any other point in your menstrual cycle, pregnancy protection begins after seven days of pill usage. In the first seven days of pill use, consider using an additional birth control method, such as a condom, for penis-in-vagina intercourse.
For progestin-only pills (POPs or mini-pills): Pregnancy protection starts after two days of consistent pill use, regardless of when you begin. During the initial 48 hours on the pill, be sure to use an additional form of birth control, such as a condom, if engaging in vaginal sex. It is crucial to take progestin-only pills at the same time daily. If you exceed the usual time by more than 3 hours, employ a backup birth control method for the next 48 hours.
Slynd: A newer progestin-only pill variant operates slightly differently. Immediate pregnancy protection is provided when starting Slynd within the initial five days of your period. If you’re beginning Slynd at any other point in your cycle, use an alternative birth control method (e.g., condoms) for the first seven days of penis-in-vagina sex. Unlike other progestin-only pills, Slynd does not require strict adherence to the same 3-hour window daily.