Impact of Cesarean Delivery and Breastfeeding on Secretory Immunoglobulin A in the Infant Gut Is Mediated by Gut Microbiota and Metabolites

Pre-labor and post-labor cesarean delivery and early childhood adiposity in the Canadian Healthy Infant Longitudinal Development (CHILD) Cohort Study

BACKGROUND/OBJECTIVES

Delivery by cesarean section (CS) compared to vaginal delivery has been associated with increased risk of overweight in childhood. Our study examined if the presence or absence of labor events in CS delivery altered risk of overweight in early childhood (1-5 years) compared to vaginal delivery and if this association differed according to infant sex.

SUBJECTS/METHODS

The study included 3073 mother-infant pairs from the CHILD Cohort Study in Canada. Data from birth records were used to categorize infants as having been vaginally delivered, or delivered by CS, with or without labor events. Age and sex adjusted weight-for-length (WFL) and body mass index (BMI) z scores were calculated from height and weight data from clinic visits at 1, 3 and 5 years and used to classify children as overweight. Associations between delivery mode and child overweight at each timepoint were assessed using regression models, adjusting for relevant confounding factors including maternal pre-pregnancy BMI. Effect modification by infant sex was tested.

RESULTS

One in four infants (24.6%) were born by CS delivery; 13.0% involved labor events and 11.6% did not. Infants born by CS without labor had an increased odds of being overweight at age 1 year compared to vaginally delivered infants after adjustment for maternal pre-pregnancy BMI, maternal diabetes, smoking, infant sex and birthweight-for-gestational age (aOR 1.68 [95% CI 1.05-2.67]). These effects did not persist to 3 or 5 years of age and, after stratification by sex, were only seen in boys (aOR at 1 year 2.21 [95% CI 1.26-3.88]).

CONCLUSION AND RELEVANCE

Our findings add to the body of evidence that CS, in particular CS without labor events, may be a risk factor for overweight in early life, and that this association may be sex-specific. These findings could help to identify children at higher risk for developing obesity.

Perinatal and early life factors and asthma control among preschoolers: a population-based retrospective cohort study

BACKGROUND

Preventing poor childhood asthma control is crucial for short-term and long-term respiratory health. This study evaluated associations between perinatal and early-life factors and early childhood asthma control.

METHODS

This retrospective study used administrative health data from mothers and children born 2010-2012 with a diagnosis of asthma before age 5 years, in Alberta, Canada. The outcome was asthma control within 2 years after diagnosis. Associations between perinatal and early-life factors and risk of partly and uncontrolled asthma were evaluated by multinomial logistic regression.

RESULTS

Of 7206 preschoolers with asthma, 52% had controlled, 37% partly controlled and 12% uncontrolled asthma 2 years after diagnosis. Compared with controlled asthma, prenatal antibiotics (adjusted risk ratio (aRR): 1.19; 95% CI 1.06 to 1.33) and smoking (aRR: 1.18; 95% CI 1.02 to 1.37), C-section delivery (aRR: 1.11; 95% CI 1.00 to 1.25), summer birth (aRR: 1.16; 95% CI 1.00 to 1.34) and early-life hospitalisation for respiratory illness (aRR: 2.24; 95% CI 1.81 to 2.76) increased the risk of partly controlled asthma. Gestational diabetes (aRR: 1.41; 95% CI 1.06 to 1.87), C-section delivery (aRR: 1.18; 95% CI 1.00 to 1.39), antibiotics (aRR: 1.32; 95% CI 1.08 to 1.61) and hospitalisation for early-life respiratory illness (aRR: 1.65; 95% CI 1.19 to 2.27) were associated with uncontrolled asthma.

CONCLUSION

Maternal perinatal and early-life factors including antibiotics in pregnancy and childhood, gestational diabetes, prenatal smoking, C-section and summertime birth, and hospitalisations for respiratory illness are associated with partly or uncontrolled childhood asthma. These results underline the significance of perinatal health and the lasting effects of early-life experiences on lung development and disease programming.