Ruptured chronic ectopic pregnancy presenting with a negative urine pregnancy test

An acute ectopic pregnancy is one of the most common gynaecological emergencies in clinical practice. The diagnosis is usually established by a combination of clinical examination findings, correlated with sonographic and laboratory results. However, a chronic ectopic pregnancy (CEP) may occur when the ectopically implanted gestation, mostly in the fallopian tubes, invades the underlying structures, causing protracted destruction at the site of implantation. Individuals may present with subacute or chronic abdominal pain, abnormal vaginal bleeding, amenorrhoea and a low bHCG. The correct diagnosis is often only established following laparoscopy or even histologically after the operation. The authors present the case of a woman in her 30 s presenting with severe right sided abdominal pain and a failing pregnancy at 10 weeks gestation. Her urine pregnancy test was negative, but her serum bHCG was 18 IU/L. A transvaginal ultrasound scan confirmed a ruptured right tubal ectopic pregnancy. A laparoscopic salpingectomy was performed. This case provides an important reminder that a CEP should always be considered in the differential diagnosis of women of reproductive age presenting with acute lower abdominal pain, despite a negative urine pregnancy test.