A False Negative Pregnancy Test in a Patient with a Hydatidiform Molar Pregnancy

To the Editor: Determination of pregnancy status is vital in the workup of a patient presenting with vaginal bleeding or lower abdominal pain. We report a case of false negative results on urine and serum pregnancy tests as a result of the “high-dose hook effect.” A 26-year-old woman (gravida 1, para 1) presented to the emergency department, reporting lower abdominal pain, vomiting, and several weeks of irregular vaginal bleeding. On examination, she was anxious and in moderate discomfort, and her heart rate and blood pressure were elevated. Her abdomen was soft, with a tender lower abdominal mass. Pelvic examination revealed . . .