A 39 year old primigravid woman who was 36 weeks pregnant presented to the maternity unit with a one day history of worsening intermittent abdominal pain and vomiting. The pain was colicky in nature, with no radiation, and it was worse when she was lying flat. There had been no vaginal bleeding, no change in bowel habit, and no urinary symptoms. She had been previously well and had no medical history of note. She was tachycardic (117 beats/min), but respirations, blood pressure, and temperature were normal. On examination she was tender in the right upper quadrant and epigastrium, with no guarding. Before the general surgeons were contacted, the obstetric team had taken a history and carried out an examination, including a speculum examination, assessment of fetal heart sounds, and cardiotocography monitoring. All fetal assessments were normal and speculum examination excluded preterm labour. Routine haematological and biochemical investigations showed a raised alkaline phosphatase, consistent with pregnancy, and a raised amylase (113 U/L; reference range 30-100). Abdominal ultrasound showed a normal single fetus and no intraperitoneal free fluid or gallstones. Despite regular analgesia and antiemetics the pain worsened gradually over the next 48 hours, with constant bilious vomiting. After discussion with the general surgeon on call, it was decided that the possibility of bowel obstruction needed to be investigated, so abdominal radiography was performed (fig 1⇓). ### 1 What are the important differential diagnoses for abdominal pain during pregnancy? #### Short answer Initial differential diagnosis includes gastroenteritis, cholecystitis, appendicitis, acute pancreatitis, ureteric colic, bowel obstruction, and placental abruption. #### Long answer It is difficult to make a clinical diagnosis in pregnant women with …