Which test is used for screening pregnancy?

The HCG Quant test is specifically designed to measure the concentration of human chorionic gonadotropin (hCG) in a person's blood. This hormone is produced during pregnancy, primarily by the placenta shortly after an embryo attaches to the uterine lining. The presence of hCG in the bloodstream is a definitive indication of pregnancy, and because its levels can be quantitatively assessed, the test can also provide information on the progression of the pregnancy.

In contrast, estradiol is a form of estrogen and is involved in various functions in both male and female bodies, but it is not a direct indicator of pregnancy. Free T4 pertains to thyroid function and is not related to pregnancy screening. Cortisol is a stress hormone that plays roles in metabolism and immune response, rather than indicating pregnancy status. Therefore, the HCG Quant test is the most suitable choice for effectively screening for pregnancy.