After menopause, the ovaries will fail and there will be no more mature follicles to discharge. However, perimenopausal women can still theoretically become pregnant because although they are no longer menstruating regularly, they still have mature follicles in their ovaries and their endometrium is of normal thickness, so it is theoretically possible to become pregnant. The basic requirements for pregnancy are the presence of viable sperm in the vagina and the presence of mature follicles in the woman. Postmenopausal women do not ovulate anymore and the endometrial lining is too thin to allow a fertilized egg to settle properly, so there is no possibility of pregnancy for postmenopausal women. Therefore, postmenopausal women do not need to use contraception when having sex and do not need to worry about pregnancy. However, since the vagina is dry and astringent, painful intercourse may occur during sexual intercourse as a normal physiological reaction. The time of complete menopause means that menstruation has not occurred for more than one year. If menstruation is still occurring for two or three months or six months, it is not menopause, but perimenopause. During this period, it is necessary to use contraception, because theoretically there is still a possibility of pregnancy.