‘Game changer’ discovery sparks urgent trials to see if taking iron supplements could cut the risk of deadly congenital heart disease in newborns
Scientists have found that pregnant women low in iron are more likely to have a baby with a deadly heart defect.
The “game changer” discovery has sparked urgent trials to see if taking iron supplements could cut the risk of congenital heart disease in newborns. The condition is the most common kind of birth defect, diagnosed in an average of 13 babies every day in the UK, and is a major cause of death. Nearly a quarter of pregnant women in the UK are thought to have anaemia.
Researchers now estimate that anaemia in pregnant women may account for around one in 20 congenital heart disease cases in the UK.
The study looked at data from 16,500 mothers and found that, if the mother was anaemic in the first 100 days of pregnancy (around the first three months), the likelihood of having a child with congenital heart disease was 47% higher.
Study leader Duncan Sparrow, associate professor from Oxford University, said: “Knowing that early maternal anaemia is so damaging could be a gamechanger worldwide. Because iron deficiency is the root cause of many cases of anaemia, widespread iron supplementation for women – both when trying for a baby and when pregnant – could help prevent congenital heart disease in many newborns before it has developed.”
The researchers previously found a link between anaemia during pregnancy and congenital heart disease in mice. To investigate this link, they used anonymised data from GP records to see what was happening in mothers and babies.
More than 2,700 mothers who had a child with congenital heart disease were identified and matched with women whose children did not have the condition.
Blood test results from the first 100 days of each pregnancy were then used to determine whether the mothers had anaemia at that point. In the group of mothers who had a child with congenital heart disease, 4.4% had anaemia. This was compared to 2.8% of mothers having anaemia whose children did not develop congenital heart disease.
Dr Sonya Babu-Narayan, clinical director at the British Heart Foundation and consultant cardiologist, said: “If low iron turns out to be one of the culprits, then replenishing iron levels during early pregnancy when the baby’s heart is forming could have significant benefit for a baby’s lifelong heart health. Larger studies are needed to confirm the finding and determine which type of congenital heart disease may be linked to low iron.
“It is also important to note that the usual risk of having a child with a congenital heart disease is around 1%, so even with the increase that this study suggests, the individual risk for people with no family history of congenital heart disease is still relatively small.”
