Population Research Discovery Seminars

Cesarean delivery can prevent maternal and fetal mortality but has been associated with adverse child health outcomes. These associations may result from altered immune and metabolic influences stemming directly from surgery—i.e. microbial and antibiotic exposures during and after parturition, delayed skin-to-skin contact and breastfeeding initiation—or may reflect underlying gestational risk factors that necessitate cesarean delivery. Research across populations with varied reproductive patterns, feeding practices, and disease risks may help to elucidate the context-specific pathways linking cesarean delivery to adverse child health outcomes.

I present findings from research on cesarean delivery and infant infectious morbidity and breastfeeding outcomes in a peri-urban Indigenous Qom community of rural Argentina. I analyzed birth records and longitudinal observations collected from 91 Qom mother-infant dyads between 2011-2014. Nearly half of mothers surveyed delivered by cesarean section, with higher rates observed in association with early to preterm birth and young and older maternal age. However, compared to vaginally-born infants, cesarean-born infants had no elevated risk of gastrointestinal illness and unexpectedly reduced risk of respiratory illness. Birth mode was not associated with exclusive breastfeeding duration, but cesarean-born infants were weaned later than vaginally-born infants. I discuss these findings in relation to unique aspects of Qom mothers’ traditional feeding, infant care practices, and experiences with institutionalized birth and health care—all of which may differently influence the causes and consequences of cesarean birth in this community as compared to elsewhere in Latin America and the U.S.

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Melanie Martin is an Assistant Professor of Biological Anthropology at the University of Washington who studies biocultural influences on growth, development, and reproduction. She is the Co-Director of the Chaco Area Reproductive Ecology Program in northern Argentina, which conducts community-engaged work on maternal and infant health with Indigenous Qom/Toba communities and a public hospital. She is also currently conducting research on maternal-infant COVID-19 risks and immune responses with Seattle-area families. Dr. Martin’s previous work with Indigenous Tsimane families in the Bolivian Amazon examined relationships between infant feeding transitions, parasite exposure, and infant growth, microbial development, and maternal reproductive outcomes.