Few studies have explored whether fetal exposure to n-6 and n-3 fatty acids influences the inception of atopic disease.
To assess prenatal fatty acid exposures as predictors of early childhood wheezing and eczema.
In the Avon Longitudinal Study of Parents and Children, late pregnancy maternal blood samples and umbilical cord blood samples were assayed for n-6 and n-3 fatty acids (percentage of total red cell phospholipid), and mothers were asked about wheezing and eczema in their children. We measured associations of 11 n-6 and n-3 fatty acid exposures with wheezing at 30 to 42 months, with wheezing patterns defined by presence (+) or absence (-) of wheezing during 2 periods, 0 to 6 months and 30 to 42 months (transient infant, +/-; later-onset, -/+; persistent, +/+; n=1191 and n=2764 for cord and maternal analyses, respectively), and with eczema at 18 to 30 months (n=1238 and n=2945 for cord and maternal analyses, respectively).
In cord blood red cells, the ratio of arachidonic:eicosapentaenoic acid was positively associated with eczema (adjusted odds ratio [OR] per doubling, 1.14; 95% CI, 1.00-1.31; P=.044), the ratio of linoleic acid:alpha-linolenic acid was positively associated with later-onset wheeze (OR, 1.30; CI, 1.04-1.61; P=.019), and the ratio of alpha-linolenic acid:n-3 products was negatively associated with later-onset wheeze (OR, 0.86; CI, 0.75-0.99; P=.040). However, these associations were no longer significant after adjusting for multiple comparisons.
It seems unlikely that fetal exposure to n-6 and n-3 fatty acids is an important determinant of early childhood wheezing and atopic disease.