Fetal growth trajectory and risk for eczema in a Saudi population

Background: Recent studies in Western cohorts have identified associations between increasing fetal abdominal circumference (AC) during mid-pregnancy and increased risk for eczema and atopy. We sought to replicate these findings in a Saudi population where antenatal environmental exposures are different compared with Western countries. Methods: A Saudi birth cohort was recruited to relate maternal dietary intake and fetal growth to wheeze, eczema, and rhinitis in the first 2 yrs. Fetal size was determined from routine ultrasound scan measurements in the second and third trimesters and birthweight was noted. Parent-reported outcomes during the first 2 yrs were acquired by telephone-administered questionnaire. Results: There were 1076 mothers recruited. AC was determined in 562 for the second, in 632 for the third, and in 281 for both second and third trimesters. A history of eczema was determined in 814 children at 2 yrs of age. There was an inverse relationship between change in abdominal circumference between the second and third trimesters for eczema (OR 0.66 per z score increase in AC [95% CI 0.49, 0.89]), and the quartile with the greatest faltering growth were at increased risk compared with other groups (p ≤ 0.045). Change in fetal size between the third trimester and birth was not associated with altered eczema risk. There were no associations between fetal growth and wheeze at the age of 2 yrs. Conclusions: Our findings contrast observations made in Western populations but nonetheless suggest that factors associated with changing fetal growth trajectory in the second half of pregnancy are also relevant to atopy development on the global setting.