BETA HUMAN CHORIONIC GONADOTROPIN (BHCG)

Clinical significance

HCG is the most important placental hormone. It maintains the function of the corpus luteum, during initial weeks of pregnancy and prevents it from lysis.

Clinical applications

• Diagnosis of normal pregnancy (much more early indicator and reliable than urine pregnancy test).
• To exclude any suspicion of a positive pregnancy.
• Diagnosis of ectopic pregnancy

Raised in:

• In normal pregnancy hCG levels double approximately every 48 hours.
• Male patients with testicular tumours are positive for hCG.
• Hydatidiform mole

Normal in:

• Non pregnant state
• Fetal death

Ectopic pregnancies or abnormal intra-uterine pregnancies have circulating hCG levels below expected values for that gestational period: after an initial rise these levels plateau or fall.