Is enhanced fetal growth a risk factor for the development of atopy or asthma?

Background: The aetiological factors underlying the worldwide increase in t he prevalence of asthma and the international patterns of the prevalence of asthma are not well understood. This has led to consideration of factors s uch as fetomaternal health which may programme the initial susceptibility t o allergic sensitisation, or contribute to the development of asthma indepe ndently of sensitisation. Methods: A number of epidemiological studies have examined the relationship between birth anthropometric measures las a marker of fetomaternal health and the subsequent development of asthma and atopy in childhood or adult li fe. Results: Some, but not all of these studies have reported a relationship be tween enhanced fetal growth and an increased risk of asthma and/or atopy. Conclusion: These findings raise the hypothesis that factors responsible fo r fetal growth may also lead to programming of the developing respiratory o r immune systems, predisposing to the subsequent development of asthma and/ or atopy. This hypothesis may explain, in part, the increasing prevalence o f asthma and atopy over recent decades, which has occurred concurrently wit h secular trends for improved fetomaternal health, as measured by anthropom etric measurements at birth.