Caesarean section and children’s health: A quasi-experimental design

Abstract

The prevalence of inflammatory child health conditions—such as asthma, eczema, and food allergy—and their associated costs have increased rapidly over the last 30 years. While environmental factors likely underpin these increases, recent studies explain only a fraction of the trend and rely on associational methods. Caesarean (or C-) section rates increased dramatically in the period of interest, and this method of delivery is an understudied environmental factor linked to child health outcomes via the gut microbiome. We fuse 22 years of birth cohort data from the United States National Surveys of Children’s Health with C-section rates from the National Vital Statistics System generated for subgroups based on state, sex, race, Hispanic origin, and birth year. Then, we model the effects of C-section on rates of asthma, eczema, and food allergy using a quasi-experimental fixed effects design. We find that C-section significantly predicts food allergy, with qualitatively significant implications.

Keywords:

• child health
• caesarean section
• quasi-experiments
• gut microbiome
• hygiene hypothesis
• asthma
• eczema
• food allergy

Notes

1 Jessica Polos is based in the Department of Sociology and Center for Demography and Ecology, University of Wisconsin–Madison. Jason Fletcher is based in the La Follette School of Public Affairs, the Department of Sociology, and the Center for Demography and Ecology, University of Wisconsin–Madison. Please direct all correspondence to Jessica Polos, 4412 Sewell Social Sciences Building, 1180 Observatory Drive, Madison, WI 53706, USA; or by E-mail: [email protected]

2 The authors gratefully acknowledge research support from the Center for Demography and Ecology at the University of Wisconsin–Madison, which receives core support from the NICHD (P2C HD047873, T32 HD07014).