TOPLINE:

Children born to mothers who had excessive weight gain during pregnancy had higher odds of developing allergic diseases such as asthma, rhinitis, and allergic sensitization, according to findings from a Portuguese birth cohort study.

METHODOLOGY:

• Researchers analyzed data from the Generation XXI Birth Cohort in Portugal to examine the associations of maternal prepregnancy BMI and gestational weight gain with the development of asthma, rhinitis, eczema, food allergy, anaphylaxis, or allergic sensitization in offspring from early childhood through adolescence.
• Data on gestational weight gain from 6901 mother-child pairs and data on maternal prepregnancy BMI from 7280 mother-child pairs were collected.
• Investigators assessed allergic outcomes via parental questionnaires.

TAKEAWAY:

• Children of mothers with excessive gestational weight gain based on Institute of Medicine guidelines had higher odds of developing asthma at age 7 years (adjusted odds ratio [aOR], 1.30; 95% CI, 1.01-1.66) and 13 years (aOR, 1.29; 95% CI, 1.01-1.65), and rhinitis at age 4 years (aOR, 1.48; 95% CI, 1.10-1.98).
• Children whose mothers were in the highest gestational weight gain z-score tertile had higher odds of developing asthma at age 7 years (aOR, 1.33; 95% CI, 1.03-1.72), rhinitis at age 4 years (aOR, 1.54; 95% CI, 1.13-2.09), and allergic sensitization at age 10 years (aOR, 1.44; 95% CI, 1.05-1.97).
• Prepregnancy overweight or obesity was associated with lower odds of eczema at age 13 years, compared with underweight or normal weight (aOR, 0.73; 95% CI, 0.60-0.88).

IN PRACTICE:

“Our results reinforce the value of promoting healthy weight gain during pregnancy as a potential strategy for reducing allergy risk in the next generation,” the authors of the study wrote.

SOURCE:

Mónica Rodrigues, with University of Porto, Porto, Portugal, was the corresponding author of the study, which was published online on May 6, 2026, in Pediatric Allergy and Immunology.

LIMITATIONS:

The study relied on self-reported prepregnancy weight and parental reports of allergic disease diagnoses. Only data on total gestational weight gain were available; trimester-specific trajectories were not captured.

DISCLOSURES:

Generation XXI was funded by Programa Operacional de Saúde. This study was supported by FCT Fundação para a Ciência e Tecnologia, I.P. The authors reported having no relevant conflicts of interest.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.