Maternal Modification and Breastfeeding
Clinical guidelines have recommended exclusive breastfeeding for the first 4 – 6 months of life to prevent atopic disease (Prescott & Tang, 2005), however the role of breastfeeding in allergy prevention is still unclear in the scientific literature. Protective factors and allergy inducing factors have both been identified in breast milk (Friedman & Zeiger, 2005). Differences in methodology such as length and exclusiveness of breastfeeding, atopic outcome measured and ages of follow up have also made past studies difficult to compare.
Breastfeeding in those with an atopic history has been found to reduce the risk of asthma and food allergy at age 7 however the risk reversed for asthma at age 14 (Matheson et al., In Press). A non randomized cohort study of 1037 children in New Zealand found any duration of breastfeeding longer than 3 weeks increased the risk of asthma and atopy at age 13 (Sears et al., 2002).
A randomised trial of 13 889 mother-infant pairs found that an increase in breast feeding length and exclusivity in the intervention group had no effect on risk of developing allergic symptoms of asthma, hay fever and eczema or positive SPTs at a follow up of 6 years (Kramer et al., 2007).
Some studies have found a preventative effect of breast feeding on allergy occurrence. Breastfeeding has been found to prevent infantile eczema (Matheson et al., In Press). A Swedish study assessed duration of exclusive and partial breast feeding separately in a birth cohort of 4089 infants (Kull, Wickman, Lilja, Nordvall & Pershagen, 2002). There was a positive effect for breast feeding which was much more profound with extended exclusive breast feeding than partial breast feeding (Kull et al., 2002). A preventative effect of breastfeeding was also found in a 17 year non randomized study (Saarinen & Kajosaari, 1995). Breast feeding for 6 months or longer was associated with less eczema and food allergy at age 1 and 3 compared to breast feeding for less than one month or from 1 up to 6 months (Saarinen & Kajosaari, 1995).