The standard medical advice is based on a 1998 UK government issued precautionary notice for women with a family history of atopy (asthma, eczema or hay fever) to avoid eating peanuts during pregnancy and breast-feeding as this could increase the chances of peanut sensitisation in children.
But the findings of a study by scientists Dr Tara Dean and Dr Carina Venter at the University of Portsmouth of 858 pregnant women and 660 children suggests the government medical advice is being followed mostly by first-time mothers regardless of family history of atopy. Researchers questioned the women about their diets, and two years later, conducted skin prick tests on the children to detect peanut sensitisation.
The findings revealed that 65 per cent of women (whether atopic or not) followed the advice and stopped eating peanuts. The skin prick tests revealed 13 out of 660 children were sensitised to peanuts (two per cent of the sample). Of this group of 13 children, 11 had a family history of atopy, while 10 out of 13 mothers said they avoided peanuts during pregnancy.
"Mothers of 77 per cent of children sensitized to peanuts had avoided peanuts during pregnancy. In this cohort study, maternal consumption of peanuts during pregnancy was not associated with peanut sensitization in the infant," the scientists wrote in a paper published this week in the Journal of Human Nutrition and Dietetics.
The scientists called for a review of the 1998 Department of Health advice issued by the Committee on Toxicity in Chemicals in Food, Consumer Products and the Environment (COT).
"It is likely that the COT advice is either misunderstood by mothers of that those who communicate that advice have not fully explained who it is targeted at," the scientists said.
"Not surprisingly, most mothers who heard the advice had heard of it through their midwives. At the first booking appointment (during the first trimester), midwives highlight certain dietary precautions to safeguard the baby's wellbeing.
"It is likely that avoidance of peanut is often communicated as blanket advice or interpreted as blanket advice regardless of family history of atopy. It has previously been shown that this 'blanket approach' causes confusion amongst mothers (Turke et al., 2005).
"This study reveals the requirement for clear, consistent factual advice and information about the real risks associated with peanut consumption during pregnancy/lactation and peanut allergy in the developing child, and specifically to whom these risks apply."
The research was carried out at The David Hide Asthma and Allergy Research Centre on the Isle of Wight (UK).