The fertile period is 4-5 days before and after the day of ovulation, about 10 days. The rest are safe periods. In women who have regular periods, the day of ovulation tends to be about 14 days before the next menstrual period. If you have intercourse 4-5 days before or after the day of ovulation, you are likely to get pregnant, and this is the fertile period. Avoiding intercourse during the fertile period can provide natural contraception, called safe-period contraception. However, the safe period is not very reliable and is prone to unwanted pregnancy. Women may ovulate early or late, or may ovulate extra, depending on their mood and physical condition. Women can check the date of ovulation according to basal body temperature, cervical mucus examination, ovulation test paper and other methods to improve the success rate of safe period contraception. Women’s contraceptive method selection, detailed consultation with a professional doctor, under the guidance of the doctor to use appropriate methods of contraception, in order to reduce the number of unwanted pregnancies.