An adolescent female presented with an acute abdomen and elevated beta-human chorionic gonadotropin levels and underwent a laparoscopy for a suspected ruptured ectopic pregnancy. Intraoperatively, a ruptured haemorrhagic corpus luteal cyst and tissues suggestive of products of conception were noted in the same ovary. Histology confirmed an ovarian ectopic pregnancy. Haemorrhagic ovarian cysts, and ectopic pregnancies, can cause acute pelvic pain in women of childbearing age. Their similar clinical signs and symptoms pose a diagnostic dilemma for any gynaecologist. Ruptured corpus luteal cysts, as well as ruptured ovarian ectopic pregnancies, should be considered rare but differential diagnoses in women presenting with acute abdominal pain, an adnexal mass and ultrasound features of haemoperitoneum. The mainstay of treatment is a diagnostic laparoscopy, which is a safe and feasible management strategy without compromising patient safety or ovarian function in the long run.