7 doctors weighed in:

How do pregnancy tests work?

7 doctors weighed in
Dr. Carolyn Thompson
Obstetrics & Gynecology
5 doctors agree

In brief: Measure hormones

Pregnancy tests measure the level of a hormone called human Chorionic Gonadotropin (hcg), which begins to be produced when the fertilized egg implants into the uterine wall.
This hormone can be measured in urine or in the blood. The blood test is the more accurate of the two methods.

In brief: Measure hormones

Pregnancy tests measure the level of a hormone called human Chorionic Gonadotropin (hcg), which begins to be produced when the fertilized egg implants into the uterine wall.
This hormone can be measured in urine or in the blood. The blood test is the more accurate of the two methods.
Dr. Carolyn Thompson
Dr. Carolyn Thompson
Thank
Dr. David Sherer
Anesthesiology

In brief: Color

The test strip changes color when there is the presence of certain hormones in the urine released after conception.

In brief: Color

The test strip changes color when there is the presence of certain hormones in the urine released after conception.
Dr. David Sherer
Dr. David Sherer
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