Most of the time, menstrual cramps may be caused by excessive tilting of the uterus or tightening of the cervical opening, which may lead to menstrual cramps, but it is not related to sex and will not affect menstrual cramps. The menstrual blood will be discharged smoothly, thus relieving menstrual pain, or in some cases, menstrual pain will cease after delivery. If the dysmenorrhea is caused by endometriosis, which means that the endometrium is ectopic to the myometrium, the myometrium has a small amount of bleeding during menstruation and the bleeding does not come out, thus causing dysmenorrhea, it will not improve after delivery.