September 09, 2016
2 min read

Smaller fetal size increases risk for asthma, lung deficiency up to age 15

You've successfully added to your alerts. You will receive an email when new content is published.

Click Here to Manage Email Alerts

We were unable to process your request. Please try again later. If you continue to have this issue please contact

Reduced fetal size in the first trimester was associated with an increased risk for asthma and reduced lung function that extended to children aged 15 years, according to data presented at the European Respiratory Society International Congress in London.

Stephen Turner, MD, of the University of Aberdeen in the United Kingdom, and colleagues determined in an earlier study that smaller fetal size during the first (T1) and second (T2) trimesters was associated with an increased risk for asthma in children up to age 10 years, according to a press release. Their current research assessed lung function and asthma risk for children aged 5 to 15 years.

To evaluate the link between asthma risk and lung function in children who were of smaller fetal size, the researchers recruited 2,000 pregnant women seen at a clinic in Aberdeen from 1997 to 1999. All underwent ultrasounds in T1 and T2 to measure their children’s fetal size, and children were followed up at ages 5, 10 and 15 years for asthma and lung function. The researchers used a general estimating equation to determine the relationship between T1 size and asthma at each time point. A linear mixed effects model was employed to measure T1 and T2 z scores, and lung function from pregnancy to 15 years was stratified for asthma outcome.

Turner and colleagues reported that each increased z score for T1 size correlated with a 22% reduced risk for asthma at all ages studied (OR = 0.78; 95% CI, 0.63-0.97), and for every T1 z score increase, the mean FEV1.z score improved (0.13; 95% CI, 0.03-0.22). Persistent asthma correlated with reduced fetal size at T1 and T2 and FEV1 at all child ages vs. children who exhibited no asthma or exhibited transient/late onset asthma.

“First trimester fetal size, a surrogate for fetal lung size, is relevant to symptoms and respiratory physiology through 15 years of age,” Turner said in the release. “These findings suggest that antenatal factors contribute to life-long respiratory well-being.

“What we need to do now is first replicate these findings in other cohorts and then work out whether it is fetuses which start off small and stay small who have the worst outcomes, or whether it is those that start off normal size and then become small who are in trouble. Ultimately, any intervention is going to boil down to mothers not smoking or drinking, having a balanced diet and taking regular exercise.” – by Kate Sherrer


Turner S, et al. Fetal origins of persistent childhood asthma. Presented at: ERS International Congress; Sept. 3-7, 2016; London.

Disclosure: Infectious Diseases in Children was unable to confirm relevant financial disclosures at the time of publication.