There is increasing evidence that the prenatal window represents a critical period in which the developing immune system may be primed toward an allergic phenotype. Studies have investigated the role of a number of maternal environmental exposures on subsequent allergic disorders in the offspring. We summarize findings from recent studies on prenatal environmental factors influencing IgE levels, atopy, and early asthma.
A building literature supports the influence of maternal exposure to environmental pollutants, such as allergens, traffic-related air pollution, tobacco smoke, and organochlorine compounds and social factors on allergic outcomes. More novel associations have been investigated, such as the effect of prenatal exposures to phthalates, bisphenol A, and magnetic fields. There is also rising interest in epigenetics as a pathway of action by which maternal exposure affect immune health.
Emerging research highlights the challenges of investigating in-utero exposures and of relating exposures to such a heterogeneous and complex outcome as allergic disease. Further research is needed on the mechanisms by which prenatal exposure influences allergic response in childhood and how postnatal, familial and social factors, and sex can modify disease outcomes. Epigenetics is a promising new frontier, and likely one of several explanatory factors.
aDepartment of Environmental Health, Boston University School of Public Health
bDivision of General Pediatrics, Boston University School of Medicine, Boston, Massachusetts, USA
Correspondence to Junenette Peters, ScD, Department of Environmental Health, Boston University School of Public Health, 715 Albany St, Room 440W, Boston, MA 02118, USA. Tel: +1 617 638 4679; fax: +1 617 638 4857; e-mail: firstname.lastname@example.org