ABSTRACT
BACKGROUND: Müllerian duct abnormalities are common and may be related to pregnancy complications. Few cases of ectopic pregnancy within an undescended Fallopian tube have been reported, and they present a diagnostic challenge. CASE: A 32-year-old pregnant woman had three presentations to the emergency department for increasing left upper abdominal pain, chest pain, shortness of breath, and eventual hemodynamic instability in the setting of right unicornuate uterus and undiagnosed undescended left adnexa. CONCLUSION: This case presents a rare diagnosis in the differential diagnosis of chest pain and shortness of breath, as well as pregnancy of unknown location. If intraperitoneal hemorrhage is present in a woman with a positive pregnancy test but pregnancy is not detected within the pelvis, it is advisable to investigate the upper abdomen for ectopic pregnancy.