False-negative hCG test results usually involve urine and are due to the qualitative nature of the test. Reasons for a negative test result may include an hCG concentration below the sensitivity threshold of the specific test being used, a miscalculation in the onset of the missed menses, or delayed menses from early pregnancy loss. Delayed ovulation or delayed implantation are other reasons for low hCG concentrations at the time of testing, which yields a false-negative result.