Flags for future disease: postpartum cardiometabolic risk & prevention by understanding the contribution of breastfeeding and the influences of the COVID-19 pandemic

Abstract

Cardiovascular disease is a global leading cause of mortality in women. Pregnancy has been called a ‘stress test’ due to pathological indicators such as gestational diabetes (GDM) that can ‘flag’ increased risk for cardiometabolic disease. Of concern is the global rising prevalence of type 2 diabetes (T2DM) and cardiometabolic disease, with pandemics identified to increase population risk for both. There are measures to reduce cardiometabolic disease risk such as exercise and diet. Breastfeeding has also been identified to reduce T2DM risk, however the impact on next pregnancy GDM risk is unknown. It is also unknown how changes in maternity care during the COVID-19 pandemic impact cardiometabolic risk. The aim of my thesis was to investigate cardiometabolic risk for women during the pandemic with a focus on gestational diabetes and breastfeeding.

Quantitative and qualitative studies were undertaken for this thesis. An initial novel quantitative pilot study identified that high intensity breastfeeding (HIBF) was associated with a lower glucose level on the OGTT (published). In my follow-up study of 5,374 participants, HIBF was associated with 47% reduced odds of an abnormal fasting glucose in a subsequent pregnancy OGTT (aOR 0.53; 95%CI 0.38-0.75; p<0.01). A mixed methods approach examined potential influences on cardiometabolic health in the first year of the pandemic during the low COVID-19 prevalence period (three publications). Further qualitative methodology was used to explore the disruption to maternity care and identified disrupted social support and vulnerable groups in the high migrant population.

This thesis presents novel findings identifying optimal breastfeeding patterns can have direct metabolic benefits in a subsequent. The results of our COVID-19 research provides unique insights into how service and community changes alone impact obstetric outcomes and potential cardiometabolic risk in a high migrant population.