Quick answer
The Indirect Coombs Test (ICT) costs ₹550 at Live Line Health Care. Screens the blood for free antibodies against red cells, most often in Rh negative pregnant women to see whether anti-D antibodies have formed. No fasting is needed. It uses a blood sample and the report is usually ready within 24 hours.
Also known as: ICT, Indirect Antiglobulin Test, IAT, Antibody Screen, Red Cell Antibody Screen, Coombs Test Indirect, Indirect Coomb Test, Anti-D Antibody Test
What is the Indirect Coombs Test?
The Indirect Coombs Test (ICT), also called the indirect antiglobulin test or antibody screen, looks for antibodies against red blood cells that are floating freely in the liquid part of your blood. The lab mixes your serum with screening red cells of known types, then adds a Coombs reagent. If the cells clump, your blood contains an antibody that could attack red cells carrying that marker. Such antibodies usually form after exposure to someone else's red cells, during pregnancy or a past transfusion.
In antenatal care this test matters most for Rh negative mothers. If the baby is Rh positive, a few of its red cells can enter the mother's blood, especially at delivery, and her body may make anti-D antibodies. In a later pregnancy these can cross the placenta and destroy the baby's red cells, causing anaemia and jaundice. A negative ICT means no such antibodies have formed, so a preventive anti-D injection can still help. The direct Coombs test is different: it looks at antibodies already stuck to red cells, so it is used for a jaundiced newborn or suspected haemolysis, while the ICT is the mother's screening test.
What it measures: Free antibodies in the serum that can bind to red blood cells, and, if one is found and your doctor asks, its strength (titre).
Parameters included (2)
- Indirect Antiglobulin Test (Negative or Positive)
- Antibody Titre, if Positive and Requested
Why is this test done?
- Antenatal screening of Rh negative mothers, usually at the first visit and again around 28 weeks
- Checking for antibodies before a preventive anti-D injection is given
- Following the antibody level (titre) during pregnancy when an antibody has been found
- Screening for red cell antibodies before a blood transfusion
- Checking a mother who has had previous miscarriages, transfusions or an affected baby
When should you get tested?
- You are pregnant and your blood group is Rh negative
- Your partner is Rh positive or his blood group is not known
- A previous baby had jaundice or anaemia from blood group incompatibility
- You had a miscarriage, abortion, ectopic pregnancy or bleeding in pregnancy without anti-D cover
- You have had blood transfusions in the past
How to prepare for the Indirect Coombs Test
- 1No fasting is needed for this test.
- 2Carry your blood group report and your antenatal card, so that the result can be matched to your pregnancy record.
- 3Tell staff if you have received an anti-D injection, and when, because it can make the ICT positive for several weeks.
- 4If the test is being repeated to follow a titre, carry your earlier reports so the values can be compared.
Indirect Coombs Test normal range
| Parameter | Typical reference range |
|---|---|
| Normal result | Negativeno free red cell antibodies detected |
| Positive result | Positivethe antibody may then be identified and its titre reported, for example 1:8 or 1:32 |
| Anti-D titre often treated as significant | 1:16 or higherthe exact cut-off varies between centres |
This is not a numeric test. A titre is reported only when an antibody is present, and a higher titre means a stronger antibody. Ranges are typical adult values and vary between labs, age and sex. Always use the range printed on your report and discuss results with your doctor.
Understanding your results
- A negative ICT in an Rh negative mother means she has not formed anti-D. Her doctor will usually advise preventive anti-D injections at the recommended times.
- A positive ICT shortly after an anti-D injection may simply be the injected antibody. Your doctor will consider the timing before drawing conclusions.
- A positive ICT with no recent anti-D means the mother has made an antibody. The obstetrician will identify it and follow the titre, and may arrange ultrasound checks of the baby.
- A rising titre during pregnancy usually leads to closer monitoring of the baby, sometimes in a specialist centre.
- Before a transfusion, a positive screen means the blood bank must find compatible units, which may take extra time.
Indirect Coombs Test – FAQs
What is the price of the Indirect Coombs Test?
The Indirect Coombs Test (ICT) costs ₹550 at Live Line Health Care, at all 45 centres and for home sample collection.
What is the difference between ICT and DCT?
The indirect test (ICT) looks for free antibodies in the mother's or patient's serum. The direct test (DCT) looks for antibodies already attached to red cells. ICT is used in pregnancy screening and before transfusion, while DCT is used for a jaundiced newborn or suspected red cell breakdown.
Why is ICT done for Rh negative pregnant women?
To find out whether the mother has started making anti-D antibodies against an Rh positive baby. If not, a preventive anti-D injection can stop them forming. If she has, the baby needs closer monitoring. Your obstetrician will tell you when the test should be done.
When is the indirect Coombs test done in pregnancy?
Commonly at the first antenatal visit and again around 28 weeks, before routine anti-D is given. Some doctors repeat it more often if an antibody is found. Timing differs between practices, so follow the schedule your obstetrician sets and keep all your reports together.
Does the father need to be tested?
His blood group helps. If the father is also Rh negative, the baby will usually be Rh negative too, and the risk is low. If he is Rh positive or unknown, the mother is managed as though the baby may be Rh positive. Your doctor will advise on this.
What does an ICT titre of 1:16 mean?
It means the antibody can still be detected after the serum is diluted 16 times. Higher titres mean stronger antibodies. For anti-D, many centres treat 1:16 or above as the point for closer checks of the baby. Your obstetrician will explain what your result means.
Can ICT be positive after an anti-D injection?
Yes. The injection contains anti-D, so a weak positive result is common for several weeks afterwards. Tell the staff and your doctor the date of any injection. Doctors often take the ICT sample before giving anti-D to avoid this confusion.
Where can I get the Indirect Coombs Test done?
At any of our 45 Live Line Health Care centres in 40 cities across Andhra Pradesh and Telangana, including Hyderabad, Visakhapatnam, Warangal, Kakinada and Nellore, or book home sample collection.
Medical disclaimer: This information is for general awareness only and is not a substitute for professional medical advice. Please consult a qualified doctor to interpret your results and before starting or changing any treatment.