- Design
- Multisite randomised trial, 1:1, high vs standard maternal egg and peanut intake
- Population
- 2,137 pregnant women whose unborn child had at least two relatives with allergic disease
- Primary outcome
- IgE-mediated egg or peanut allergy in the infant at 1 year
- Effect
- 7.8% vs 8.4%; relative risk 0.93 (95% CI 0.69 to 1.26; P = 0.65)
PrEggNut randomised 2,137 pregnant women whose unborn child had at least two biological relatives with medically diagnosed allergic disease. One group ate at least 6 eggs and 60 peanuts a week and the other no more than 3 eggs and 30 peanuts, from before 23 weeks of gestation until four months of lactation.
IgE-mediated egg or peanut allergy in the infant at one year was 7.8% (83 of 1,066) in the high egg-peanut group and 8.4% (89 of 1,064) in the standard-diet group (relative risk 0.93, 95% CI 0.69 to 1.26; P = 0.65). Safety measures were similar.
The trial was done in infants at raised risk of allergy, and it tested maternal intake rather than early introduction in the infant. It does not address the separate question of when to introduce eggs and peanuts to the baby, which is a different intervention.
- Do not advise pregnant or breastfeeding women to eat large amounts of egg and peanut to prevent allergy in the baby.
- Allergy at one year was 7.8% vs 8.4%, with an interval compatible with a modest benefit or a modest harm.
- This trial does not change advice on introducing allergenic foods to the infant.
- Safety measures were similar between the two diets.
Why it matters
It tests the idea that allergy can be prevented in utero and through breast milk, and finds no support for it at this dose.
Don't overread it
The trial tested maternal diet only, in a high-risk group, and says nothing about infant feeding.
The statistics, in plain English
An interval of 0.69 to 1.26 includes 1, so the trial excludes a large benefit but cannot rule out a small one in either direction. The result is neutral, not proof of harm or of no effect at all.
Read the rest in the app
You have read your two free briefings this month. The app carries all 27 specialties, every morning, free — and this finding is waiting in it.
Scan to keep reading on your phone. No account needed to start.
Tomorrow morning, before your first patient
One edition a day for top clinical updates, written by the desk, every claim tied to its paper. Six minutes.
Get the app — free