Women will have menstruation even if they do not ovulate. Ovulation in women is influenced by the secretion of the pituitary gland, which causes the follicles to grow and develop to about 2 cm, and ovulation occurs during ovulation. Menstruation is regulated by the ovarian secretion of estrogen and progesterone, which thicken the endometrium, and women will have menstruation when these two hormones retreat at the same time. During puberty, breastfeeding or menopause, although women have their periods every month, their ovaries do not ovulate every month, sometimes only once every few months, which is normal, mainly due to the imbalance of hormone levels secreted by the pituitary gland in the body. Therefore, if a woman wants to get pregnant, it is best to have intercourse when ovulation is detected during the ovulation period, in order to increase the conception rate.