The chances of getting pregnant if you have intercourse without a condom can only be expected if you have intercourse during ovulation or not. Ovulation is about 14 days before menstruation, and if the menstrual cycle is very regular, around 28-30 days, having intercourse during ovulation without contraception can cause the chance of pregnancy. If you do not want to get pregnant, you should take oral emergency contraceptives, which may have a 60% chance of pregnancy at this time. If the menstrual cycle is very irregular and there is no way to estimate the exact ovulation period, having intercourse at any time can result in a 30-40% chance of pregnancy. Again, if you do not want to conceive, you should take oral emergency contraceptive pills as much as possible to achieve a contraceptive purpose. If you have intercourse when you are not ovulating, there is a 10%-20% chance of pregnancy because the immature follicles are not able to unite with the egg.