Professor Mitchell is an expert in reproductive biology with over 40 years of experience in Obstetrics and Gynaecology and Reproductive Biology and has published extensively on the endocrinology of pregnancy with particular emphasis on gestational tissue expression, function and analysis of eicosanoid biosynthesis and metabolism in both cells and biological fluids. Prof Mitchell has developed methods for the assessment of placental functioning and for prognosis, diagnosis and treatment of pathologies including preterm labour, recurrent miscarriage and preeclampsia. In addition, Prof Mitchell has extensive experience in biomarker discovery and development and evaluation of in vitro diagnostics. He developed, characterised and validated several early immunoassays for specific prostaglandins and their metabolites before radioactive tracers were available. More recently, Prof Mitchell has developed mass spectrometry–based assays for eicosanoids. He has initiated collaborative studies on the biogenesis, function and bioactivity of placenta-derived exosomes and characterization of the protein and miRNA content.

Professor Mitchell has had consistent grant funding for research from major funding bodies in the UK, U.S.A, NZ and Australia [e.g. MRC (UK), NIH (USA), HRC (NZ) and ARC], gaining over $50 million in grant funding during his career. The quality of his research led to election as a Fellow of the Royal Society of New Zealand (FRSNZ) and subsequently was awarded a prestigious James Cook Fellowship by RSNZ to study epigenetics and preterm labour. His leadership skills and expertise led to his appointment as Deputy Executive Dean of The Faculty of Medical and Health Sciences, University of Auckland. He has supervised over 130 postgraduate students and fellows.