Graduate Research Degree Awarded - Isobel Todd

Congratulations to Isobel Todd - Graduate Research Degree Awarded 22nd January 2026

Degree: Doctor of Philosophy
Supervisors: Prof David Burgner, Dr Jessica Miller, Prof Lars Henning Pedersen, Dr Maria Magnus
Advisory Committee: Prof Sharon Goldfeld, Prof Lisa Hui, Prof Joshua Vogel

Thesis Title: Prenatal, birth, and early childhood risk and protective factors for infections in children

Thesis Summary:

This thesis explored how several key factors during the pregnancy, birth, and early childhood period influence the frequency and severity of infections across childhood. In a systematic review and meta-analysis, a consistent association between caesarean section birth and increased risk of hospitalised infections in children was observed. In a large birth cohort study, children with prenatal antibiotic exposure, born by caesarean section, or with shorter breastfeeding duration had an increased risk of hospitalised infections but showed minimal differences in the total number of infections experienced. In a registry-based analysis in two countries, a cumulative increased risk of hospitalised infections was observed for multiple adverse perinatal exposures with preterm birth being a particularly important risk factor. In sibling comparison analyses using registry data, the associations between prenatal antibiotic exposure and caesarean section birth with hospitalised infections in children were lower in magnitude or null when compared to the results from the full registry cohort.

Date awarded: 22nd January 2026