How long until the ring starts working?

It depends on when you put the ring in and if you are switching from a hormonal method of birth control. The ring is effective immediately if you get it inserted within 5 days of the start of your period, you’re switching from another method of hormonal birth control that you’ve been using consistently, it’s been less than 7 days since a first or second-trimester pregnancy ended, or you gave birth in the last 21 days. Otherwise, it will take 7 days after you insert the ring for it to be effective at preventing pregnancy. So, you’ll need to use a backup method, like condoms or internal condoms if you have sex during that time.