The physiological period is also known as menstruation, the pelvic cavity will be congested, after the physiological period intercourse some patients will have abdominal pain, there may be two main reasons: first, may be due to the stimulation of semen to make the uterus contraction, the uterus contraction after involving the peritoneum or pelvic nerves, resulting in abdominal cramping and pain; second, because the physiological period will have pelvic congestion or uterine congestion, enlargement performance, after the end of the physiological period will gradually recover, just after the end of the physiological period intercourse, the uterus and pelvic congestion symptoms may not be completely relieved, this time there may be some abdominal pain and cramping sensation.