There are two types of natural contraceptive methods: safe period contraception and in-vitro ejaculation. Safe period contraception is the avoidance of ovulation for sexual intercourse, thus achieving the effect of contraception. Ovulation is about 14 days before the next menstrual period, and the possibility of unwanted pregnancy exists 5 days before and 4 days after ovulation. It is recommended to avoid ovulation when having sex, which is one of the most common natural contraceptive methods. However, the safe period method is not absolutely safe and there is a possibility of unintended pregnancy. In vitro ejaculation is a method of contraception in which the sperm is discharged outside the body during sex and no sperm enters the vagina, preventing the sperm and egg from combining and thus playing a contraceptive role. The natural method of contraception can be used to prevent pregnancy, but there is a risk of unwanted pregnancy. It is recommended to use condoms, which are more effective and do not harm the body.