Haematology• Updated 21 October 2026

Coombs Test

A blood test that finds antibodies against red blood cells, used in pregnancy and for some anaemias.

Results: Usually within a day Specimen: Blood

Quick Summary

Primary Purpose

To check for antibodies that can harm a baby's red cells in pregnancy, or cause anaemia in adults.

What It Measures

Direct and indirect antiglobulin tests.

Preparation

No preparation needed.

The indirect Coombs test is used in Rh-negative pregnant women.

The direct test looks for antibodies stuck to red cells in haemolytic anaemia or newborn jaundice.

Antibodies in the blood.

Antibodies on red cells.

01
Preparation
Usually no special preparation. Tell the staff about medicines you take.
02
Blood sample
A small amount of blood is taken from a vein in your arm with a thin needle.
03
Afterwards
Press on the spot for a minute. A small bruise is common; you can go back to normal activities.

Discuss with Doctor

Normal ranges differ between laboratories, ages and sexes; always use the range printed on your report and ask your doctor what your results mean.

A positive test means antibodies are present; your doctor will explain what follow-up is needed.

Last updated 21 October 2026. For more detail, see these trusted health organisations.