When a woman becomes pregnant, doctors can ask to test pregnancy in blood or urine. Fertilized egg secretes a hormone called hCG. This hormone is used to develop placenta. This hormone is present in blood and majority of its quantity is wasted in urine. Detection of this hormone in urine or blood is pregnancy test.
hCG levels 0-5 means no pregnancy. In urine test, its levels should be 25. In blood tests, small amounts are also detectable. At 4 weeks pregnancy hCG levels 3-426. So, blood pregnancy tests measure hCG for confirmation of pregnancy.
hCG levels 0-5 means no pregnancy. In urine test, its levels should be 25. In blood tests, small amounts are also detectable. At 4 weeks pregnancy hCG levels 3-426. So, blood pregnancy tests measure hCG for confirmation of pregnancy.