Abstract A 32-year old Caucasian was admitted at 14 weeks of gestation with hypotension and weight loss. Family members noted that she appeared “tired” prior to pregnancy. Past medical history included primary hypothyroidism treated with thyroxine (100μg/day). She had a healthy daughter aged 2.5 years who had been born small for gestational age. At about 8 weeks of gestation she started to vomit several times a day. She was treated with antiemetics and intravenous fluids. Following discharge she remained nauseated, weak and lightheaded and lost about 8 kg of weight. After readmission she appeared ill and dehydrated, BMI 16.6 kg/m2, BP 90/60 mmHg supine, 70/50mmHg upright (with faint-like sensation), normal heart sounds, chest clinically cle...