The risk of giving birth to a child with congenital heart disease is approximately 50% higher for mothers with anaemia compared to those without, research has found.
Published in BJOG: An International Journal of Obstetrics & Gynaecology, the researchers said the findings have the potential to substantially reduce the number of children born with congenital heart disease – currently estimated as approximately 2.5 million globally each year.
Using data from the UK Clinical Practice Research Datalink GOLD database of electronic health records, the researchers analysed electronic health records from 2,776 women who had a child diagnosed with congenital heart disease. These cases were matched to 13,880 women whose children did not have a congenital heart disease diagnosis.
The researchers used the World Health Organization definition of anaemia (< 110 g/L haemoglobin) and analysed women with a haemoglobin measurement in the first 100 days of pregnancy and a child diagnosed with congenital heart disease within the first five years of life.
The findings showed that of 123 mothers whose babies had congenital heart disease, 4.4% of the women had anaemia. Of the 390 mothers whose babies had normal heart function, 2.8% of the mothers had anaemia. After adjusting for potential influencing factors, the odds of giving birth to a child with congenital heart disease were 47% higher among anaemic mothers.
Dr Duncan Sparrow PhD, associate professor and British Heart Foundation senior basic science research fellow at the University of Oxford, and the corresponding author on the study, said: ‘We already know that the risk of congenital heart disease can be raised by a variety of factors, but these results develop our understanding of anaemia specifically and take it from lab studies to the clinic. Knowing that early maternal anaemia is so damaging could be a game-changer worldwide.’
The Population Attributable Fraction (PAF) was calculated to be 1.4% from the 2.8% prevalence in the population measured. However, previous estimates suggest levels of anaemia may be as high as 7% in the first trimester and up to 13% in some areas. In these cases, maternal anaemia may account for up to 6.2% of UK congenital heart disease cases.
Dr Sparrow added: ‘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 suggested a clinical trial of periconceptional iron supplementation would be beneficial in light of their results, stating it would be a minimally invasive and low-cost intervention which could prevent some congenital heart disease if iron deficiency anaemia is proven to be a cause.
Last year, research found that diet and exercise interventions before and during pregnancy could lower cardiovascular risk in children of obese mothers.
A version of this article was originally published by our sister publication Nursing in Practice.
