Hemoperitoneum as a result of coital injury without associated vaginal injury. Hemoperitoneum as a result of coital injury without associated vaginal injury is an extremely rare entity, and evidence by only five cases that have been reported in the medical literature to date. We report five additional cases encountered in two medical centers. Two of these were ruptured corpus luteum cysts, one was a laceration of the round ligament, another was a laceration of an ovary, and the fifth was rupture of a serous cystadenoma. This diagnosis should be considered in patients with hemoperitoneum after coitus. 