Positive Coombs Test in Newborns – What it is, When it is Done and How to Take Care

6 min read

Written by Editorial Team

Editorial Team

Coombs Test Newborns

A baby who is tested positive in the Coombs test will need a little extra medical care after childbirth. They will become completely healthy fairly quickly. Positive Coombs Test in newborns means the mother and the baby’s blood types have combined. A baby is supplied with nutrients and oxygen through the placenta membrane. It also ensures their blood doesn’t mix together.

During delivery, a breach in this membrane may result in the mother and the baby’s bloodstream receiving each other’s blood. The little one has a frail immune system at this tender age. So, their red blood cells begin to get damaged. This causes jaundice or anemia as well in different cases. Healthcare providers do some tests post-childbirth. And one such test is the Coombs test. It helps to uncover whether the antibodies from the mother’s bloodstream have invaded the baby’s body.

In This Article

What is Positive Coombs Test in Newborns?

A baby and a mother can have different blood groups. It’s normal. But in some rare instances, the two blood groups or types mix together. Healthcare providers collect a blood sample from the baby’s umbilical cord to check if such mixing has taken place. It’s called a Coombs test or direct antibody test (DAT).

The baby can fall ill with jaundice, anemia, and other conditions if two blood groups are combined. But it’s not a very serious matter even if your baby has tested positive on the Coombs test. A little extra medical care will take care of the problem. Most Coombs test-positive babies don’t need to spend extra time in the hospital following delivery.

When is Coombs Test in Newborns Done?

Coombs test done

A positive Coombs test in newborns can only be checked after delivery. It’s a type of precaution to prevent future diseases. As the baby grows and develops in the mother’s womb, you might wonder how the baby gets nourishment. An organ named the placenta membrane is formed inside the womb or uterus when a woman is pregnant. It is like a bridge between the mother’s body and the baby’s.

Through the placenta membrane, nutrients and oxygen are delivered to the baby. Moreover, the placenta makes sure that the baby’s and the mother’s blood don’t mix together. But sometimes, a placenta breach can happen during childbirth. As a result, the baby’s blood enters the mother’s body and vice versa.

1. Blood Donation

Take this example, a person named Sam is about to get a blood donation from a donor. Healthcare providers need to ensure that both blood groups are compatible. Otherwise, Sam’s immune system will see the donated blood as a threat and begin destroying those red blood cells.

2. Mother and Baby Having Different Blood Groups

Similarly, the baby and the mother can belong to different blood groups. If mixing happens due to placental abnormality, and the two blood groups are compatible, like in the case of donations, it’s not a problem. However, in instances of incompatible blood groups combining, the mother’s immune system, with its antibodies will start to destroy the red blood cells entered into her bloodstream from the baby’s body.

Furthermore, red blood cells from the mother’s body have also entered the bloodstream of the baby. But their immune system is tender so it won’t be able to react much. And because of the placental breach, the antibodies from the mother’s body will move inside the baby and there also will begin destroying the red blood cells.

Following the damage and breaking down of red blood cells, bilirubin (a type of yellow pigment) is produced in excessive quantities. This causes jaundice. Other health issues can also emerge.

Types of Coombs Tests

Coomb test types

There are mainly two types of Coombs Tests which are performed on babies;

1. Direct Coombs Test (Direct Antiglobulin Test/DAT)

It’s an inspection of the red blood cells to check for any antibodies attached to them. A positive result means antibodies are present, and can cause harm. This procedure takes place after childbirth.

2. Indirect Coombs Test (Indirect Antiglobulin Test/IAT)

This test comes under one of the prenatal routine tests. It helps to check the presence of antibodies in the mother’s body. Her system might have created them during a previous pregnancy or during some blood transfusion in the past.

What to Expect From Coombs Positive Test in Babies?

A baby who is tested positive can have the below-mentioned health complications. This is the reason that their red blood cells are breaking down at a rapid rate.

1. Jaundice

The white portion of the eyes and the skin turns yellow. When red blood cells break down, bilirubin (an orange-yellow colored pigment) is formed in excess in the bloodstream. It accumulates under the skin and consequently, it gets a yellow tone.

Mild jaundice is common among many newborns. It gets healed by itself. But some vigilance is necessary, especially if the baby is Coombs positive. The risk of getting jaundice is greater in this case.

In fact, a study published by the National Library of Medicine suggests that a positive Coombs test can indicate the occurrence of Jaundice in newborn babies.

[Read : Jaundice in Newborn Babies]

2. Anemia

Anemia occurs when the baby is deficient in red blood cells. Red blood cells are like delivery boys; they carry oxygen all over the body. Therefore, babies with anemia can be very sleepy, feed poorly, take more breaths than usual, and have a higher heart rate.

How to Take Care of a Coombs Positive Baby?

Coombs positive baby

Coombs-positive babies need some more medical supervision than usual. But there’s nothing to fear.

  • Some specially designed physical exams help to predict the degree of jaundice and anemia that can happen.
  • Jaundice is cured with phototherapy. The idea behind this is that the baby’s body gets assistance to break down bilirubin. In addition, their system naturally removes it once bilirubin is broken down with the help of light therapy.
  • To treat anemia, IV treatments are very helpful. In short, the medical team will address this problem, as it’s not a very serious condition. It won’t affect your baby’s future in any way.

Are There Any Long-Term Complications in Coombs-Positive Infants?

Your baby may fall sick again after treatment with jaundice or anemia. You may need to take your baby to the hospital for a follow-up checkup. But that’s all. The baby’s and mother’s blood doesn’t mix anymore once the delivery is done. So, the root of the problem is taken care of during childbirth. Just the after-effect remains for a short while. The baby’s body begins producing its own red blood cells normally after delivery, and the issue is eliminated.

[Read : Baby’s First Week Checkup]

What Happens If the Coombs Test is Negative?

It’s good news. There aren’t any antibodies to red blood cells which would pose a threat. A negative test means your baby is healthy, and there’s no risk of anemia and jaundice arising from it.

Positive Coombs test in newborns, if detected, can be effectively handled by the doctors. It might concern you whether being diagnosed with jaundice or anemia at this tender age will leave a mark on their future. But these minor health complications won’t weaken their future health in any way. So let it not become a distraction from celebrating your newborn’s arrival.


1. What Anemia Has Positive Coombs?

In a positive Coombs test, antibodies are bound to red blood cells. If the red blood cells get damaged, the condition is called hemolytic anemia.

2. What is the Normal Range For Direct Coombs Test?

The normal range for the Coombs test means the baby is tested negative. 1+ indicates hardly positive, while 4+ means very positive. So below the range of 1+ should be considered risk-free.

Read Also: Newborn Heel Stick Test For Babies – Significance And Complications

Editorial Team,

With a rich experience in pregnancy and parenting, our team of experts create insightful, well-curated, and easy-to-read content for our to-be-parents and parents at all stages of parenting.Read more.

Responses (0)

Please check a captcha

Want curated content sharply tailored for your exact stage of parenting?

Discover great local businesses around you for your kids.

Get regular updates, great recommendations and other right stuff at the right time.


Our site uses cookies to make your experience on this site even better. We hope you think that is sweet.