In a group of mostly lean, pregnant women, delivery by cesarean section was associated with a two-fold increase in risk for offspring overweight at age 20 years when compared with vaginal delivery, according to study findings published in International Journal of Obesity.
“There are several important variables to consider that could confound the association between C-section delivery and offspring overweight or obesity,” Susanne Hansen, PhD, of the Center for Fetal Programming at Statens Serum Institute in Copenhagen, Denmark, and colleagues wrote. “This includes maternal prepregnancy BMI, but also other shared risk factors, [including] pregnancy complications, such as pre-eclampsia or gestational diabetes.”
Although some studies have accounted for maternal prepregnancy BMI, few studies to date have also adjusted for pregnancy complications, the researchers noted in study background. Most previous studies, they wrote, have examined offspring overweight or obesity exclusively by measures of BMI, usually collected by self-report, and lacked information on underlying cardiometabolic parameters.
Hansen and colleagues analyzed data from 695 adult offspring born to women participating in the Danish Fetal Origins cohort, a population-based cohort established in 1988-1989. Researchers contacted mother-offspring pairs in 2008-2009 for the follow-up study; offspring completed a self-administered questionnaire, attended a clinical exam (n = 443) and provided a fasting blood sample to measure cardiometabolic biomarkers, including serum adiponectin, leptin, plasma insulin, serum triglycerides, LDL and HDL cholesterol, and apolipoprotein A and B. Standardized cutoffs for BMI were used to define offspring overweight and obesity.
Within the cohort of offspring, 51 (7%) were born by cesarean section. At age 20 years, 125 (18%) were overweight or obese.
Researchers found that birth by cesarean section was associated with a two-fold increase in risk for offspring overweight or obesity at age 20 years (OR = 2.02; 95% CI, 1.07-3.82) in crude analysis; a similar estimate persisted after adjustment for maternal prepregnancy BMI (OR = 1.94; 95% CI, 1.02-3.7) and after additional adjustment for sociodemographic factors and behavioral and clinical characteristics (OR = 2.17; 95% CI, 1.1-4.27).
Offspring delivered by cesarean section had a mean BMI that was 0.83 kg/m² higher than that of offspring delivered vaginally; mean waist circumference was 1.64 cm greater. Treating maternal BMI as a continuous variable did not change results, according to researchers.
Delivery by cesarean section was also associated with elevated serum lipid and leptin levels; mean serum cholesterol was 9% greater (95% CI, 1.1-16.5); mean LDL cholesterol was 13% greater (95% CI, 1-25.5) and mean ApoB levels were 0.08 g/L higher (95% CI, 0.03-0.15) compared with offspring delivered vaginally. Mean serum leptin levels of offspring delivered by cesarean section were 73.1% higher (95% CI, 5.9-183.1) compared with offspring delivered vaginally.
“Our findings suggest that the potentially deleterious adverse effect of being born by C-section is not limited to body weight, but may also results in an adverse cardiometabolic risk profile at early adult age,” the researchers wrote.
The researchers noted that changes in the infant gut microbiome that typically occur during a vaginal delivery may influence the associations, but more research is needed. – by Regina Schaffer
Disclosures: The authors report no relevant financial disclosures.