Pregnancy is possible on the 5th day of menstruation. If the menstrual cycle is 28-30 days and the period lasts about 7 days, the 5th day after menstruation belongs to the ovulation period and there is a possibility of pregnancy because the sperm can survive in the woman’s body for 2-3 days after discharge and the egg has the ability to fertilize for 1-2 days after discharge. If the menstrual cycle is 35 days, the 5th day of menstruation is a safe period, the chance of pregnancy is low, but there is a certain possibility, because ovulation is affected by a lot of reasons, such as environmental factors, emotional factors, etc. If ovulation is early, it is easy to cause pregnancy, irregular menstruation will affect ovulation, resulting in early or receding ovulation, so it is easy to have the possibility of pregnancy, so it is usually recommended to do a good job of contraception, you can The use of condoms, birth control pills, contraceptive rings, etc., but the pill has side effects, it is not recommended to take the pill often, especially the emergency contraceptive pill is likely to cause endocrine disorders.