Learn The BasicsFetal and neonatal alloimmune thrombocytopenia (FNAIT) is a rare blood disorder affecting babies before or just after they are born. It is caused by the mother’s immune system mistakenly attacking her baby’s platelets increasing the risk of bleeding.
Here are some FAQs about the disease.
Who is at risk of FNAIT?
FNAIT is a rare disease that occurs when the proteins found on the surface of the baby’s platelets do not match the ones found on the surface of the mother’s platelets.
This occurs in around one in 400 pregnancies. However, it does not always cause thrombocytopenia or low platelet counts, which only affects around one in 1500 pregnancies.
Did something I do or ate cause this?
FNAIT has not been linked to any environmental or dietary factors. So nothing that the mother does can cause a baby to develop FNAIT.
Does FNAIT run in families?
The proteins that are expressed on the surface of platelets are determined by genetics. So if a woman has a baby affected by FNAIT, it means that they have a rare protein combination on their platelets, which their sisters may also have, putting them at risk of also having a baby with FNAIT.
How do I know if my baby is at risk of developing FNAIT?
FNAIT is not routinely screened for during pregnancy so it is difficult to know if your baby might be at risk of developing the disease during a first pregnancy.
The risk of having a second baby affected by FNAIT is much higher if the first baby had FNAIT.
Can I breastfeed my baby?
FNAIT is caused by the mother’s antibodies destroying the platelets of her baby. However, if the baby is well enough to feed, it is ok to breastfeed a baby with FNAIT as it is rare for the antibodies to be transmitted to the baby through breast milk.
Are there any treatments?
In the case of a previous pregnancy where the baby was affected by FNAIT, a pregnant woman may be treated with intravenous immunoglobulin and corticosteroids to dampen her immune system and reduce the risk of her baby developing FNAIT.
A baby at risk of FNAIT whose platelet count is below 30 x 109/L should be given a platelet transfusion, even if they are not experiencing bleeding.
There is also a new experimental treatment called nipocalimab that is currently being tested in clinical trials that could reduce the levels of antibodies in the circulation of the mother, which attack the baby’s platelets.
Can FNAIT cause long-term problems?
In very severe cases, FNAIT can lead to bleeding in the brain also known as intracranial hemorrhage or ICH. If this happens, a baby can have brain damage and lifelong disability. In very severe cases, ICH can even be lethal.
Will my baby always have low platelet counts?
Low platelet counts caused by the destruction of the baby’s platelets by the mother’s antibodies usually resolve within a few weeks of birth, and the baby’s platelet counts return to normal. This means a baby affected by FNAIT will not be at risk of low platelet counts throughout their life.
