Soo worked as a clinical midwife, and then a clinical/research midwife between 1985 and 2000.  In 2001 she joined UCLan  where she is now the Professor of Midwifery Studies. 

Her main research focus is the nature of, and cultures around, normal birth. She is currently working with WHO on a range of maternity care guidelines, and has been an author on papers in three Lancet Series (Midwifery, Stillbirth, and Reducing Caesarean Section). Among other funding sources, she has been PI or CI on studies funded by RfPB. HTA, PHR and UKRI (ESRC). She has published over 160 peer reviewed papers, and has undertaken research using a wide range of qualitative and quantitative methods.