Calculation of safety period:

Contraceptive method: Normal women of childbearing age have 1 menstrual cycle every month, from the beginning of this menstrual cycle to the 1 day of the next menstrual cycle, which is called 1 menstrual cycle. From the perspective of contraception, women's menstrual cycle can be divided into menstrual period, ovulation period and safety period. Safe period contraception is a contraceptive method that stops sexual life during ovulation.

Women's ovulation date is generally around 14 days before the next menstruation. After the egg is discharged from the ovary, it can live in the fallopian tube for 1-2 days, waiting for fertilization; Male sperm can maintain fertilization ability in female reproductive tract for 2-3 days, so it is easy to get pregnant during sexual intercourse within a few days before and after ovulation. To be on the safe side, we call the first 5 days and the last 4 days *** 10 days together with the ovulation date as the ovulation period. Because sexual intercourse during ovulation is easy to conceive, ovulation is also called susceptible pregnancy or dangerous period.

The safety period is divided into pre-ovulation safety period and post-ovulation safety period. The period from the day when menstruation is clean to the day before ovulation is the safe period before ovulation. From the end of ovulation,

The first day to the day before the next menstrual cramp is the safe period after ovulation. The safe period after ovulation is safer than that before ovulation. This is because some women are sometimes affected by environmental changes and emotional fluctuations and ovulate in advance, so that the safety period before ovulation will be shortened without knowing it, so that the safety period before ovulation is unsafe. It is rare for the ovary to ovulate twice in a menstrual cycle, that is, the second ovulation will not occur from ovulation to the next menstruation, so the safe period after ovulation is safer.

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