There is also a possibility of pregnancy if you have intercourse after ovulation. The egg can survive for 1-2 days after discharge and the sperm can survive for 2-3 days in the female genitalia, so you can get pregnant if you have intercourse 1-2 days after ovulation. If you have intercourse 4 days after ovulation, the chances of pregnancy will be reduced. If you have intercourse without contraception and have delayed menstruation, then consider that it is caused by pregnancy. It is best to go to the hospital in time to have blood drawn to check the blood HCG, you can also use early pregnancy test paper and other tests to determine pregnancy. If you are planning to get pregnant, it is best to have intercourse 2-3 days before ovulation or 1-2 days after ovulation to have a good chance of getting pregnant. It is best to calculate the ovulation period according to their own menstrual cycle, you can also do ultrasound to monitor the follicles, to determine the ovulation situation, it is best to have intercourse on the day of ovulation to maximize the chances of pregnancy, pay attention to the ovulation period can not be too frequent intercourse.