A new long-term study published in BMJ Medicine suggests that children born to very obese mothers (those with a body mass index [BMI] of 35 or higher) are at increased risk of being admitted to a hospital for infection in their first five years of life.
The study comes from data collected as part of the Born in Bradford study, a UK analysis that assessed short- and long-term mother and child health outcomes. All participants gave birth to a living child at the Bradford Royal Infirmary from March 2007 and December 2010. In total, the study included 9,540 singleton births from 2007 to 2011, born to 9,037 mothers, with the children followed up from birth to about 15 years of age.
Maternal obesity is a serious problem worldwide.
“Obesity is a state of inflammation that can interfere with the development and function of the immune system,” the authors explained. "Maternal obesity is a serious problem worldwide…that has almost doubled from 8.7% in the 1990s to 16.3% between 2010 and 2019."
Being born to an obese mother could affect a child's immune system and microbiome, and a growing body of evidence has linked maternal obesity to childhood asthma, obesity, and metabolic diseases.
A fourth of expectant moms obese
About one-third, or 30% of the women, were overweight, and 26% were obese, which included 10% who were grades 2 to 3 obese (BMI of 35 or above), based on first trimester BMIs.
Higher first-trimester maternal BMIs were associated with increased risk of serious infections in children, especially when obesity was grade 2 or higher. In total, the authors tracked 5,009 hospital admissions between birth and age 15;19% of children were admitted once, 6% twice, and 4% three or more times.
The highest admission rates were in children under 1 year of age (134.6 admissions per 1,000 person-years at risk), which decreased with age to 19.9 per 1,000 person-years by age 5 to 15 years.
Children born to women with obesity had an adjusted rate ratio of 1.41 (95% confidence interval [CI], 1.13 to 1.77) at under 1 year, and an adjusted rate ratio of 1.53 for hospital admissions for infection by age 5 to 15 years, compared to children born to women with healthy BMIs.
Results hold true across infection types
"We found similar trends for hospital admissions for upper respiratory tract infections, lower respiratory tract infections, gastrointestinal infections, and multisystem viral infections as for overall infections, with hospital admission rates increasing with maternal body mass index. Adjustment for confounders did not affect the results," the authors wrote.
Surprisingly, breastfeeding was not found to be protective against childhood infections, but the authors said only breastfeeding through 6 weeks postpartum was assessed among some study participants.
"The findings of our study highlight the need for public health campaigns and additional support for healthcare professionals to help women of reproductive age achieve and maintain a healthy body weight," the authors wrote.
