1.Hormone VI: 2nd-4th day of menstruation, fasting before 10:00 am. Suitable for people: irregular menstruation, very low menstrual flow, ovulation disorder. 2, Fallopian tube: 3-5 days after menstruation, without sexual intercourse. Suitable for people: no contraception for more than 1 year after marriage, infertility after delivery, abortion, purging. 3.Sperm: 3-7 days after sperm discharge. Suitable for people: men who are infertile after marriage.