This is a rare case of abdominal wall endometriosis with a uterine connection in a woman with no previous history of gynecologic or obstetric pathology and/or surgical interventions with localized persistent pain cyclically aggravated by menses in the right side hypogastric region for several months and small palpable mass in the referred location. The mass was also cyclically more palpable during menses. 

The MRI study revealed a lesion in the anterior abdominal wall (AAW), adjacent to the rectus abdominis, without a clear cleavage plane and with 17,6mm. It also showed a filliform sinuous formation, extending anteroposteriorly from the lesion in the AAW to the uterine cavity fundus and with approximately 25mm.

In all the performed sequences the signal behavior in both findings and the uterine cavity is identical.

No other intra or extra-pelvic endometriosis lesions were found.

Extra pelvic endometriosis is a rare condition and occurs mostly due to transplantation of uterine endometrium through lymphatic, vascular, or iatrogenic dissemination. The most common site it occurs is in the abdominal wall as a result of abdominal or pelvic surgery scar and it has an incidence of 0,1%.