What should I do if I want to have sex on my fertile days?

If you’re not 100% sure you’ll avoid sex on all of your fertile days (first, make sure you know which days you are fertile) and you want to prevent pregnancy, you should use another birth control method in addition to fertility awareness-based methods.

Still not working?

If you prefer to avoid hormones, you can use (condoms or internal condoms), a diaphragm or cervical cap with spermicide.
If you had sex on a fertile day and don’t want to be pregnant, consider using emergency contraception pills or getting certain types of IUD within 5 days.
If you and your partner are having trouble sticking to the fertility awareness-based methods schedule but you want a non-hormonal method, you might want to consider the copper IUD.