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Generating a Reproducible Model of Mid-Gestational Maternal Immune Activation using Poly(I:C) to Study Susceptibility and Resilience in Offspring
09:09

Generating a Reproducible Model of Mid-Gestational Maternal Immune Activation using Poly(I:C) to Study Susceptibility and Resilience in Offspring

Published on: August 17, 2022

Number of offspring and maternal allergy

F Forastiere1, J Sunyer, S Farchi

  • 1Dipartimento di Epidemiologia, ASL RME, Rome, Italy.

Allergy
|February 25, 2005
PubMed

Insights

Larger families may reduce the risk of maternal allergic rhinitis and allergic conjunctivitis. This finding challenges the hygiene hypothesis by suggesting maternal factors, not just sibling exposure, influence atopy development.

Area of Science:

  • Epidemiology
  • Allergology
  • Reproductive Health

Background:

  • The hygiene hypothesis links reduced early childhood infections to increased allergy risk.
  • Maternal atopy is a significant predictor of childhood asthma and hay fever.
  • The role of siblings in childhood atopy is questioned if maternal atopy is inversely related to sibling numbers.

Purpose of the Study:

  • To investigate the association between reproductive history (pregnancies, live births) and maternal lifetime occurrence of allergic diseases.
  • To evaluate the hygiene hypothesis in relation to maternal atopy and family size.

Main Methods:

  • Cross-sectional study of 1755 nonsmoking women aged 35-74 in Italy.
  • Questionnaire assessing reproductive history and lifetime allergic symptoms (wheeze, asthma, allergic rhinitis, allergic conjunctivitis).
  • Statistical analysis of the relationship between number of pregnancies/live births and allergic disease prevalence.

Main Results:

  • A significant inverse relationship was observed between the number of live births and lifetime allergic rhinitis (P=0.031) and allergic conjunctivitis (P=0.011).
  • Women with 4+ children had lower odds of allergic rhinitis (OR=0.53) and allergic conjunctivitis (OR=0.42) compared to those with 0-1 child.
  • No significant association was found between reproductive history and maternal wheeze or asthma.

Conclusions:

  • Increased number of live births is associated with a reduced prevalence of maternal allergic rhinitis and allergic conjunctivitis.
  • Findings suggest maternal atopy may influence pregnancy outcomes or pregnancy may affect maternal atopy.
  • The study challenges the traditional hygiene hypothesis by highlighting potential maternal factors in atopy development.

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