An intraligamentary pregnancy is an extremely rare form of ectopic pregnancy, with only a few cases reported. We report a 20-year-old woman who had an ongoing pregnancy at about 22 weeks gestation, consulted for recurrent urinary retention and severe lower abdominal pain of two days duration. Pelvic ultrasonography revealed an extrauterine gestation of 19 weeks and four days on the left adnexal region. Exploratory laparotomy was performed that found left intraligamentary pregnancy (unruptured) measured 20 -25 cm across, attached posteriorly to the bowel (sigmoid colon) and extended to the pouch of douglas impinging on the bladder base. Resection of ectopic pregnancy was successfully performed, urine retention resolved, and the patient was discharged with no postoperative complications. Early recognition of this rare form of ectopic gestation is of considerable importance because of the risk of a life-threatening haemorrhagic complication necessitating emergency surgical intervention.