First- and second-trimester fetal size and asthma outcomes at age 10 years

Area of Science:

• Pediatric respiratory health
• Fetal development and long-term outcomes
• Epidemiology of allergic diseases

Background:

• Early fetal size is correlated with reduced asthma risk and enhanced lung function in young children.
• Existing research suggests a link between prenatal development and later respiratory health.
• The persistence of these associations into later childhood requires further investigation.

Purpose of the Study:

• To determine if associations between early fetal size and asthma symptoms/lung function persist into later childhood.
• To investigate the relationship between fetal growth patterns and respiratory health outcomes at age 10.
• To explore the association between fetal size and the development of allergic diseases.

Main Methods:

• Longitudinal study design tracking fetal measurements from the first and second trimesters.
• Respiratory questionnaires administered at 10 years of age.
• Subset of participants underwent spirometry, bronchial challenge testing, and skin-prick testing for detailed phenotyping.

Main Results:

• A 1 mm increase in first-trimester fetal size correlated with a 6% reduction in asthma risk and a 6 ml increase in FEV1.
• Reduced first-trimester size was observed in children with asthma at both 5 and 10 years.
• Persistent low fetal growth was linked to increased asthma risk (OR 2.8) and reduced FEV1 (mean 103 ml), while increasing fetal size was associated with higher eczema risk (OR 2.5).

Conclusions:

• Reduced fetal size in the first trimester is a significant predictor of increased asthma risk and impaired lung function in childhood.
• The relative change in fetal size after the first trimester is associated with an increased risk of eczema.
• These findings highlight the long-term impact of early fetal development on respiratory and allergic health.