Antibody Screening for Hepatitis B Surface Antigen (IgG)

Why This Test Is Done

Doctors may order this test if you have risk factors for hepatitis B, such as recent travel to areas with high hepatitis B transmission, exposure to infected blood or body fluids, or if you’re in a high-risk group (e.g., healthcare workers, people with multiple sexual partners, or those with chronic liver disease). It’s also used during pregnancy to screen for hepatitis B in newborns.

What to Expect Before the Test

You’ll typically have a small needle inserted into your arm to draw blood. The process takes about 5 minutes, and you may feel a brief pinch. No special preparation is needed, but inform your doctor about any medications you’re taking.

What the Test Results Mean

Positive results indicate the presence of hepatitis B surface antibodies, suggesting past infection or immunity. Negative results mean the antibodies were not detected at this time. Follow-up testing may be needed to confirm immunity or investigate exposure.

Common Causes of Abnormal Results

This test is primarily qualitative, so abnormal results are interpreted based on the presence or absence of antibodies rather than specific numeric values. A positive result may indicate immunity from prior infection, while a negative result may prompt further testing for recent exposure or other conditions.