There are several possible causes of pain in the belly after intercourse: First, the stress reaction, women’s uterus, adnexa, vagina and other located in the pelvic cavity, intercourse process due to external stimulation lasting sexual impulse, causing pelvic tissue and organ congestion, may lead to contraction of pelvic tissue, spasm and cause pain. Second, the extrusion reaction, if the male sex organ shape is larger, too much force during intercourse, may lead to a sudden rise in the abdominal pressure of women, the uterus, bladder, rectum and other pelvic visceral organs by the extrusion of external forces, the intestinal tube produced abnormal peristalsis, resulting in abdominal pain. Third, improper position, if the female superior position is used for a long time during intercourse, the uterine appendages in the pelvic cavity may pull the surrounding tissues due to the change in position, causing hidden pain in the lower abdomen or waist. Fourth, some pathological diseases of the pelvis, such as pelvic mass, ectopic pregnancy, ovarian corpus luteum cysts, etc., caused by relatively violent extrusion and shock rupture during intercourse. If the pain symptoms persist and cannot be relieved, it is recommended to go to the hospital immediately for further consultation and treatment to avoid delaying the condition.