Babies born to obese moms likely to have weaker immunity

You may want to lose your extra weight before getting pregnant, as a new study suggests that babies born to obese mothers are likely to have weaker immunity than those born to lean mothers.

The University of California, Riverside team analyzed umbilical cord blood samples of infants born to lean, overweight and obese mothers and found that pre-pregnancy maternal weight has a significant impact on the immune system of the neonate, putting such children at risk for potential diseases such as heart disease and asthma.

Team leader Ilhem Messaoudi said that the study offers potential links between changes in the offspring's immune system and the increased susceptibility and incidence of these diseases later in life.

Messaoudi added that they found that very specific immune cells in circulation, monocytes and dendritic cells, isolated from babies born to moms with high BMI were unable to respond to bacterial antigens compared to babies born to lean moms and such babies also showed a reduction in 'CD4 T-cells.' Both of these changes could result in compromised responses to infection and vaccination.

Further, the researchers found that cells (eosinophils) that play a role in allergic response and asthma pathogenesis were significantly reduced in the umbilical cord blood of babies born to obese mothers.

One potential explanation for these observations is that these cells have already moved into the lungs, which could explain the increased incidence of asthma observed later in life in children born to obese mothers.

The research is the first to show the link between maternal obesity during pregnancy and neonatal immune outcomes, and shows that changes in immunity are already detectable at birth and could persist for the lifetime of the child into adulthood.

Messaoudi added that this could change how people respond to vaccination and how they respond to asthma-inducing environmental antigens.

The study appears online in PubMed and will soon appear in the journal Pediatric Allergy and Immunology.