The danger period, in the usual sense, refers to the ovulation period of the menstrual cycle. Generally speaking, about 14 days before the next menstrual period falls within the period of ovulation. If a woman has a regular menstrual cycle, i.e. 28 to 30 days, then the 14th day before the next menstrual period is the day of ovulation. Sperm can live in a woman’s body for up to 72 hours, so the three days before and after the day of ovulation are relatively easy to get pregnant, so it is called the ovulation period, which is commonly known as the danger period. Therefore, if a woman wants to use contraception, she must pay attention to the contraceptive measures during ovulation. In addition, it should be noted that although the chances of getting pregnant during the safe period are smaller, but because the body’s endocrine secretion is constantly fluctuating, sometimes ovulation can occur during the safe period, so it is also necessary to take good contraceptive measures. In short, it is recommended that people who do not want to have children should pay attention to contraception, the common contraceptive measures are the pill, condoms and intrauterine devices, etc., can choose at your discretion.