Babies born to obese women by C-section have 5 times the risk of being obese by the age of 3 than normal children. When the same babies are born to obese mothers vaginally the risk is only 3-fold.
The same babies were found to have a higher risk of Allergies and Asthma and it is thought this increased risk is all down to a lack of exposure to protective bacteria in the vagina.
Children born to overweight mothers have more Lachnospiracea bacteria in the gut than normal children. With Caesarian operations, it seems that the child has many more of these same bacteria and this is the influencing factor.
Clearly, maternal overweight and common feeding issues are linked to the basic problem as well.
The research was conducted by the University of Alberta, Canada, lead researcher Professor Anita Kozyrskyj and published in JAMA Pediatrics, Feb 2018.