Allergy Shots in Pregnancy May Have Protective Effect for Unborn Children

Allergy shots given to pregnant women could help decrease the chance of allergies developing in their infants, according to a pilot study presented November 10th at the 2013 Annual Scientific Meeting of the American College of Allergy, Asthma & Immunology.

Researchers reached that conclusion after performing a survey of women ages 18 to 48 with a diagnosis of allergic rhinitis who received care at a single outpatient allergy clinic. The anonymous surveys, of which 800 were sent out and 192 returned, allowed the researchers to analyze 277 children (median age, 11 years; 54.2% male) and 143 mothers.

The study found a non-statistically significant trend suggestive of a decreased rate of any type of allergy in the child if the mother had received immunotherapy while pregnant (odds ratio [OR], 0.84; 95% CI, 0.38 – 1.84).

Although the results were not statistically significant, the researchers said that the trend was supported even when the data was controlled for confounding variables, such as breastfeeding, gender, presence of older siblings, and the father’s allergic status. Still, other data also was not statistically significant. For instance, the survey showed decreased rates of any type of allergic disease in children who were breastfed (OR, 0.70; 95% CI, 0.40 – 1.22) and decreased rates in children with older siblings (OR, 0.73; 95% CI, 0.44 – 1.20).

 
"Our research found trends suggesting women receiving allergy shots either before or during pregnancy reduced their child's chances of having asthma, food allergies, or eczema," said one of the study’s authors, Jay Lieberman, MD, in a news release. "Prior studies have suggested that mothers can pass protective factors to their fetus that may decrease their child's chance of developing allergic disease, and these protective factors are increased with allergy immunotherapy."

Lieberman said additional research is needed to prove allergy shots during pregnancy prevent allergies in children, but he called the “strong association” “very encouraging as allergists explore this possibility.”

Pertinent Points:
- The practice of administering allergy shots to pregnant women with allergic rhinitis might decrease the likelihood of allergies developing in their unborn children later in life.
- The pilot study results, however, were not statistically significant.