Objectives: To determine the cause of severe, disabling, groin pain. Methods: We describe in this case report 2 patients with severe groin pain. Two myoma-like masses were found on the uterus near the right round ligament. Both masses were excised via laparoscopy. Results: The pathology report of these 2 cases indicated adenomyosis. Both patients were asymptomatic after the procedure. Adenomyosis usually propagates in the myometrium, and the nodular shape of this pathology is rare. In patients with severe groin pain (menstrual or continuous), the gynecologist should think about both endometriosis of the round ligament and adenomyosis near the round ligament. Conclusion: Severe groin pain is rare but disabling. Endometriosis of the external part of the round ligament is described as a cause. In this case report, we explain that nodular adenomyosis can also be a cause.