A new study has reported that exposure to antibiotics during pregnancy and cesarean sections increase the risk of childhood obesity.
The study authors note that either a cesarean section or antibiotic use during pregnancy may alter normal maternal-offspring microbiota exchange (transfer of organisms between mother and fetus). This can result in an alternation of the microbial colonization of the infant’s intestinal tract, which can increase the susceptibility to obesity later in life. They theorized that: (1) maternal use of antibiotics in the second or third trimester (three months) of pregnancy and a cesarean section are independently related to a higher risk of childhood obesity in the offspring.
The researchers reviewed data on 727 mothers who were enrolled in the Northern Manhattan Mothers and Children Study. Of this group, they analyzed the 436 mother–child pairs followed until seven years of age who had complete data. They determined prenatal antibiotic use by a questionnaire administered late in the third trimester; the method of delivery was determined by a review of the medical record. They determined age- and sex-specific body mass index (BMI) levels and defined obesity as BMI greater than or equal to the 95th percentile. In addition to mode of delivery or antibiotic usage, they evaluated maternal age, ethnicity, pre-pregnancy BMI, maternal use of public assistance, birth weight, sex, and breastfeeding in the first year.
The investigators found that, compared to children not exposed to antibiotics during the second or third trimester, those exposed had 84% (33–154%) higher risk of obesity. In addition, second or third trimester antibiotic exposure was also positively related to BMI, waist circumference, and percentage of body fat. Independent from prenatal antibiotic usage, a cesarean section was associated with 46% risk of childhood obesity. The associations were similar for both elective and emergency cesarean sections.
The authors concluded that cesarean section and exposure to antibiotics in the second or third trimester were associated with a higher offspring risk of childhood obesity. They recommended that further studies should be conducted to support their findings. They suggested that research is also needed to determine if alterations in neonatal intestinal microbiota trigger the observed associations.
Take home message:
Based on this study, a pregnant women should discuss the pros and cons of antibiotic usage with her obstetrician. A number of studies support the overuse of antibiotics. Many factors contribute to childhood obesity; thus, if antibiotics were taken during pregnancy or a cesarean section was done, a mother should be on increased alert that her child may develop a weight problem and take precautionary measures.
