If i removed nuvaring on day 21, reinserted a new one on day 23 and had unprotected sex on day 25, what is my pregnancy risk?

Depends/ low: If the ring you removed/replaced as indicated was not worn for more than 4 weeks, then the risk of pregnancy is low. If the ring-free interval is extended beyond 1 week, pregnancy is possible, thus an extra method of birth control, such as male condoms/spermicide, must be used until the contraceptive vaginal ring has been used continuously for 7 days. Practice safe sex use condoms. Take care.

Very Low: Your pregnancy risk would be very low. Your risk of contracting a sexually transmitted infection could be higher though, depending on who your partner is and what type of relationship you are in.

1%: Your NuvaRing is contains hormones for 21 days, then you remove it for 7 days and reinsert a new once; as long as you don't leave it out for longer then 8 days you are safe. Inserting it sooner will protect you! the risk to get pregnant while on birthcontrol on average is 1%. Remember you are still at risk for std's!