The NuvaRing is highly effective as a contraceptive method. When used perfectly, it is over 99% effective at preventing pregnancy. However, with typical use, its effectiveness is about 91%, meaning around 9 out of 100 people may get pregnant within a year due to user errors. The effectiveness also depends on when during the menstrual cycle it is started; if inserted within the first 5 days of menstruation, it works almost immediately, but if started later, it takes about 7 days to become effective, during which additional contraception is recommended. The NuvaRing does not protect against sexually transmitted infections, so using condoms alongside is advised for dual protection.