Beta HCG test is a blood test that is used to confirm pregnancy. It can also be used to guide the woman’s gestational age once the pregnancy is confirmed.
What is beta hCG?
Beta HCG stands for Human Chorionic Gonadotrophy, a type of hormone that is only produced during pregnancy and is responsible for the onset of symptoms of pregnancy. For thsi reason, measuring the levels of this hormone is used to confirm pregnancy.
How does beta hCG let you know gestational age?
Beta HCG begins immediately after the egg is fertilised and its levels in the blood increase gradually until the 12th week of gestation, when they stabilize and decrease again until the end of pregnancy.
For this reason, it is important to know the amount of beta HCG in the blood as it help the doctor to better understand what gestational week the woman is in since there are intervals of values stipulated for the amount of beta HCG in each week of pregnancy:
|Gestational Age||Amount of Beta HCG in the blood test|
|Not pregnant – Negative||Less than 5 mlU/ml|
|3 weeks of gestation||5 to 50 mlU/ml|
|4 weeks of gestation||5 to 426 mlU/ml|
|5 weeks of gestation||18 to 7,340 mlU/ml|
|6 weeks of gestation||1,080 to 56,500 mlU/ml|
|7 to 8 weeks of gestation||7,650 to 229,000 mlU/ml|
|9 to 12 weeks of gestation||25,700 to 288,000 mlU/ml|
|13 to 16 weeks of gestation||13.300 a 254.000 mlU/ml|
|17 to 24 weeks of gestation||4.060 a 165.500 mlU/ml|
|25 to 40 weeks of gestation||3.640 a 117.000 mlU/ml|
How to understand the result of the calculator?
Depending on the beta HCG value that has been entered, the calculator will indicate the possible weeks of gestation based on the intervals indicated in the previous table. If the value of beta HCG is more than 1 week of gestation, the calculator may show multiple results. Thus it is important to evaluate each week of gestation, according to the development of pregnancy, as shown by the calculator as it is more reliable.
For instance, a woman with a beta HCG value of 3,800 mlU/ml may receive the results of week 5 and 6 as well as week 25 and 40. If the woman is at the beginning of pregnancy, it means that she should be in weeks 5 to 6. However, if she is at later stages of pregnancy, it is possible that the correct gestational age is 25 to 40 weeks.