Allergen-specific IgE over time in women before, during and after pregnancy

Management of allergic diseases in pregnancy

Allergic diseases like asthma, allergic rhinitis, food allergy, hymenoptera allergy, or atopic dermatitis are highly prevalent in women of childbearing age and may affect up to 30% of this age group. This review focuses on the management of allergic diseases during pregnancy. Furthermore, we discuss the challenges of counseling women with allergic diseases in the reproductive age, including considerations relevant to the ongoing SARS-CoV-2 pandemic. To create the optimal milieu for the unborn child, a multitude of immunological changes occur during pregnancy which may favor type 2 responses and aggravate disease phenotypes. In co-occurrence with suboptimal preconception disease control, this elevated Th2 responses may aggravate allergic disease manifestations during pregnancy and pose a risk for mother and child. Due to limitations in conducting clinical trials in pregnant women, safety data on anti-allergic drugs during pregnancy are limited. The lack of information and concerns among pregnant patients demands counseling on the benefits of anti-allergic drugs and the potential and known risks. This includes information on the risk for mother and child of disease aggravation in the absence of treatment. By doing so, informed decisions and shared decision-making can take place.

Sensitisation patterns and allergy outcomes in pregnant women living in the urban area

BACKGROUND

Worldwide, allergy affects more than one billion people, with particularly rising prevalence in industrialised areas. Specifically, young adults appear to be predominantly targeted for an allergy diagnosis. Allergic diseases in pregnancy are mainly pre-existing but could also occur de novo. The immunological changes while pregnant, with increased Th2 lymphocyte activity, can facilitate allergen sensitisation.

OBJECTIVE

The aim of this study was to evaluate the pattern of specific IgE (sIgE) sensitisation to common inhalant and food allergens in pregnancy, and assess its relationship to self-reported allergic disease.

METHODS

We assessed 200 pregnant women, aged 20-38 years (mean age = 29 years), participant of ELMA (Epigenetic Hallmark of Maternal Atopy and Diet) study, living in a metropolitan area, with no pregnancy associated metabolic complications, for total IgE and allergen specific IgE to 20 allergens.

RESULTS

48% of pregnant women were sensitised to at least one allergen, at a cut-off point of 0.35 kU/L and they were assigned as atopic. However 42% in atopic group were not reporting any allergic disease. The most common inhalant allergens were: pollen (24.5%) and animal dander (23.5%). The most common food allergens were: cow's milk (5.5%) and apples (4.5%). 7.5% of women reported asthma, 21.5% allergic rhinitis, 11.5% atopic dermatitis and 18.5% food allergy. 8.5% of were taking medication for asthma or allergies. Atopic dermatitis had the highest tendency to become more severe during pregnancy. Total IgE values were significantly higher in atopic women.

CONCLUSIONS

Allergic sensitisation is a common phenomenon in pregnancy. Some sensitisations could be asymptomatic. Further studies should investigate if sensitisation in mothers confers risks for immune alterations in their children.

Factors correlating with serum birch pollen IgE status in pregnant women in Hokkaido, Japan: The Japan Environment and Children's Study (JECS)

BACKGROUND

Birch pollen allergy affects pregnant women, and such allergy may affect the development of allergic diseases in their children. Using nationwide birth cohort data, this study aimed to investigate the prevalence of birch pollen IgE positivity and to identify correlating factors in pregnant women in Hokkaido, Japan, a high-latitude island.

METHODS

Participants included 6856 pregnant women. Participants responded to questionnaires regarding lifestyle factors and history of allergies. Data regarding parity, height, and pre-pregnancy weight were collected from medical records. Blood samples were obtained from participants during the first trimester of pregnancy, and serum allergen-specific IgE titers were determined.

RESULTS

The serum of 30.2% participants was positive for birch pollen IgE (≥0.35 UA/mL). Such positivity significantly correlated with a history of other allergic diseases, particularly food allergy and allergic rhinitis/hay fever. In multivariate logistic regression analysis, pre-pregnancy high body mass index (BMI ≥ 25) significantly correlated with birch pollen IgE positivity [odds ratio (OR), 1.24; 95% CI, 1.05-1.47; reference BMI, 18.5-24.9] and higher income (≥10 million yen per year; OR,0.55; 95% CI, 0.37-0.81; reference, household income < 2 million yen per year), and second quintile level physical activity (OR,0.75; 95% CI, 0.63-0.88; reference, the first quintile of physical activity) had significant protective effects.

CONCLUSIONS

Birch pollen IgE positivity in pregnant women was positively associated with food allergy, allergic rhinitis, pre-pregnant high BMI, and was negatively associated with light exercise and high household income in Hokkaido.

TRIAL REGISTRATION

UMIN000030786.