This test is commonly used to confirm pregnancy. However, it can also help to diagnose suspected tumors, post-miscarriage monitoring and detect ectopic pregnancy. After 6-7 weeks of pregnancy, hCG levels are not very helpful to test for the viability of the pregnancy. Instead, an ultrasound is done to confirm the presence of a fetal heartbeat. Low β hCG is seen in miscarriage and ectopic pregnancy while high β-hCG is observed in case of multiple pregnancies.

Why is BHCG done?

• To confirm pregnancy
• To diagnose pregnancy in the location other than the normal (Ectopic pregnancy)
• For first trimester screening of genetic diseases like Down’s syndrome and Trisomy 18
• To diagnose the presence of Gestational Trophoblastic Disease (GTD)
• To diagnose any suspected tumors like Teratomas, Testicular tumors, Ovarian germ cell tumors

What does BHCG Measure?
b-hCG test measures the levels of b-hCG in blood. b-hCG is a hormone which is normally produced by the cells in the developing placenta, during pregnancy. b-hCG levels increase during the initial period of the pregnancy. The role of b-hCG in early pregnancy is to maintain the corpus luteum (the hormone-secreting structure that develops in an ovary). During the first three weeks, production of b-hCG increases reaching to peak levels at 10th week (from the last menstrual cycle). After that, the levels of b-hCG start falling to negligible levels within a few weeks after delivery.

In men and women, b-hCG is normally found in small amounts. b-hCG is composed of two big molecules known as alpha and beta subunit. The structure of the alpha subunit is similar to the structure of Follicle-stimulating hormone and Luteinizing hormone. The beta subunit is different and is found only in b-hCG. That is why b-hCG test is done to decrease the risk of cross-reaction.