João Agostinho de Sousa1,2†, Alexander Griffiths3, Kathryn V. Dalrymple4, Sara L. White5, Ferdinand von Meyenn1,6, Lucilla Poston5, Jessica Rigutto-Farebrother1,7*, Angela C. Flynn4,8*† and on behalf of the UPBEAT Consortium
1Laboratory of Nutrition and Metabolic Epigenetics, Department of Health Sciences and Technology, ETH Zurich, Zürich, Switzerland
2Center for Scientific Computing, Theory and Data, Paul Scherrer Institute, Villigen, Switzerland
3London Metallomics Facility, King's College London, London, UK
4Department of Nutritional Sciences, School of Life Course and Population Sciences, King’s College London, London, UK
5Department of Women and Children’s Health, School of Life Course and Population Sciences, King’s College London, London, UK
6Department of Medical & Molecular Genetics, School of Basic & Medical Biosciences, King’s College London, London, UK
7Global Center for the Development of the Whole Child, University of Notre Dame, Notre Dame, Indiana, USA
8School of Population Health, Royal College of Surgeons in Ireland, Dublin, Ireland
*These authors contributed equally
†Correspondence authors: Dr. Angela C. Flynn, School of Population Health, Royal College of Surgeons in Ireland, Dublin, Ireland. Email: [email protected]; Dr. João Agostinho de Sousa, Laboratory of Nutrition and Metabolic Epigenetics, Department of Health Sciences and Technology, ETH Zurich, Zürich, Switzerland. Email: [email protected]
Characterisation of serum metal element concentrations in pregnancy enables the elucidation of relationships with maternal-fetal and neonatal health. Metal elements in the blood serve as essential cofactors for enzymatic reactions and contribute to blood gas homeostasis, hormone synthesis and physiological immune function for mother and fetus. Sub-optimal concentrations of some metals have been linked to adverse outcomes, including preterm birth, low birth weight, and impaired neurodevelopment. Maternal obesity also adversely influences metabolic status, including metal metabolism, with the potential for heightened risk of complications at delivery and long-term health issues in offspring. Research on metal element levels in pregnant women with obesity and their effects on pregnancy outcomes is however limited. This study aimed to characterize mid-gestation serum concentrations of 18 metal elements in samples from 755 pregnant women with obesity enrolled in the UK Pregnancies Better Eating and Activity Trial (UPBEAT) and identify associations with pregnancy outcomes. We found that calcium concentration tended to decrease with increasing parity, with an estimated reduction of 6.03 mg/L in multiparous participants compared to nulliparous participants (95% CI: -9.50 to -2.57 mg/L, p=0.001). Additionally, elevated manganese concentrations at mid-pregnancy were associated with an increased incidence of antepartum haemorrhage after 34 weeks (OR: 4.62, 95% CI: 2.06 to 12.4, p<0.001), and higher maternal phosphorus levels were linked to neonatal intensive care unit admissions (OR: 2.83, 95% CI: 1.75 to 4.67, p<0.001). A future focus on dysregulation of these metal elements is needed to improve understanding of the clinical associations observed.