Allergy protection from pet exposure before birth
15 August 2011
Exposure to pets before birth may protect children against developing asthma and allergies, a study suggests.
In what is believed to be the first study of its kind, researchers found levels of IgE antibodies (the type of antibodies produced in allergic reactions) were 28 per cent lower in babies whose mothers kept a cat or dog in the house while pregnant in comparison with those born into pet-free homes.
The research, carried out by the Public Health Sciences Department at Henry Ford Health System, in Michigan, US, also found that this protective effect was even stronger statistically when comparing children born vaginally to those born through caesarean section (Journal of Allergy and Clinical Immunology 2011; online 4 Aug).
The findings back the so-called 'hygiene hypothesis', the authors said. It has been theorised that vaginal births expose babies to a larger range and number of bacteria, boosting their immune system against allergies.
The researchers said it was possible a greater diversity of household bacteria provided by pets had a greater effect on babies born by caesarean.
The findings were based on blood samples collected at birth, and ages 6 months, one year and 2 years, from 1187 babies born in south-east Michigan between August 2003 and November 2007.
Last Reviewed: 15 August 2011
- 1. Havstad S, Wegienka G, Zoratti EM, et al. Effect of prenatal indoor pet exposure on the trajectory of total IgE levels in early childhood. J Allergy Clin Immunol 2011 Aug 4. [Epub ahead of print]. doi:10.1016/j.jaci.2011.06.039. http://www.sciencedirect.com/science/article/pii/S009167491101061X (accessed Aug 2011).
