The safety period is an extremely important period for couples, because sleeping together during the safety period generally does not lead to pregnancy, but the premise is to accurately calculate the safety period for women. In fact, the routine calculation of safety period is limited to women with regular menstrual cycle, while women with irregular menstrual cycle are much more complicated. So how to accurately calculate the safety period for women?

1, female safety period

There are many methods of contraception, such as tying a knot for a man, using a male condom, using a female condom, putting a ring on a woman, calculating the safety period and so on. Many men don't choose to tie a knot. One is the pain during the operation, and the other is that the knot will affect sexual function. If you wear a condom, it will affect the pleasure of making love. If you don't decide not to have children, women won't wear rings. Therefore, many people will choose to use girls' safe period for contraception. The following website tells you some secrets about girls' safety period, so that you can know more.

First of all, let's look at the calculation method of girls' safety period. From the time of contraception, girls can be divided into three periods: menstrual period, ovulation period and safety period. Normal girls of childbearing age will have 1 menstrual cycle every 28 days or so. 1 day from this menstrual period to the next menstrual period is called 1 menstrual cycle. Menstruation is the days when you come to menstruation, usually four to five days. Ovulation period is generally one week before menstruation, and one week before and after menstruation is a safe period.

Girls have an absolute safety period and a relative safety period. Absolute safety period refers to three days before menstruation and four days after menstruation, which is absolutely safe. The survival time of eggs is 24 hours, while the survival time of sperm is 72 hours, so it is not safe for three days before and after ovulation. If you want contraception, you should pay special attention to this time period. You can choose to wear a condom, and you don't need to use any contraceptive methods during the absolute safety period.

2. The probability of safe pregnancy

I once saw a biology teacher's answer on the Zhihu. Ten months later, he became a father after he personally tried safe contraception. Of course, this situation is rare, but there are indeed many incidents that lead to safe pregnancy. According to the data of the World Health Organization, in an ideal state, the probability of safe pregnancy is about 5%, but in fact, the ideal state of 5% is also difficult to achieve. If a relatively simple calculation method is adopted or one's own physiological cycle is irregular, the pregnancy rate will increase greatly, and the failure rate of clinical follow-up can reach more than 25% every year, that is, the probability of pregnancy in safe period is greater than 25%. Therefore, contraception during the safe period is not really safe.

The process of scientific pregnancy, ovulation and fertilization has certain rules. Generally speaking, healthy women ovulate regularly every month. For women with a menstrual cycle of 28 days, the ovulation date is about 14 days before menstruation, and the eggs can survive for 1-2 days after ovulation, while the sperm can survive for about 3 days after entering the female private parts. Danger period and safety period are also included, but these need to be in an "ideal state". There are not many real laws of female physiological period. In fact, many women are facing the problem of irregular menstruation.