There are so many options to prevent pregnancy. As a Menstrual cycle is of 28 days and the ovulation takes place on 14th day and it remains live there for 72 hours. So doing sex in the first week and last week of menstrual cycle is very much secure. You can ask your partner to use condoms while sex. Otherwise you can take pills before sex. Even you can go for copper Tea. Even after sex you can have morning pills that would work as complete abortion. Even vasectomy and tubectomy are other option to prevent pregnancy.
And another method which is 100% secure is do abstain from sex..
And another method which is 100% secure is do abstain from sex..