Pregnancy Test Facts
*Pregnancy test facts medically edited by: Charles Patrick Davis, MD, PhD
How do pregnancy tests work?
All pregnancy tests work by detecting a certain hormone in the urine or blood that is only there when a woman is pregnant. This hormone is called human chorionic gonadotropin (kohr-ee-ON-ihk goh-NAD-uh-TROH-puhn), or hCG. It is also called the pregnancy hormone.
hCG is made when a fertilized egg implants in the uterus. This usually happens about six days after the egg and sperm merge. But studies show that in up to 10 percent of women, implantation does not occur until much later, after the first day of the missed period. The amount of hCG rapidly builds up in your body with each passing day you are pregnant.
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Pregnancy Tests - Type Question: What type of pregnancy test did you use, and how accurate was it?
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