By: Ivy Jacobson for TheBump.com
Photo: Shutterstock / The BumpAccording to a new study from the American Association for Clinical Chemistry, 9 out of 11 of the most popular hospital urine pregnancy tests are more likely to produce a false-negative result after the fifth to seventh week of pregnancy, even though the tests perform well in the first month after conception.
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Led by Ann M. Gronowski, PhD, of the Washington University School of Medicine, St. Louis, the study shows that when a woman's egg is fertilized, it begins producing the hormone human chorionic gonadotropin (hCG), which is detected in urine or blood. However, during the fifth to seventh week of gestation, urine concentrations of an hCG variant known as the hCG beta core fragment increase rapidly, interfering with hCG detection. This is what causes false-negative test results.
In a hospital, the failure to detect a false-negative can lead to serious consequences, like administration ofRead More »from Why You Probably Want to Buy an At-Home Pregnancy Test Instead of Getting One at the Hospital