Dr Siriwardena is an obstetrician and gynaecologist at Westmead Hospital Sydney, after obtaining his medical degree from Monash University Melbourne with Honours. He was appointed as a visiting medical officer of Western Sydney Area Health Service in 2001, and has been in private practice since 2001.

He also held the position of Chairman of the Westmead Private Hospital’s O&G Department from 2006-2013 and conducted the Westmead Hospital GP shared clinic from 2001-2009. He has admitting rights as an obstetrician at Westmead Public Hospital where he delivers his high risk obstetric patients.

Dr Siriwardena is an examiner for the Royal Australian and New Zealand College of Obstetricians and Gynaecologists. He is also currently a senior lecturer at the University of Sydney and is actively involved in teaching medical students from the University. An experienced gynaecologist, his expertise covers a wide range of conditions.