Professor Yong, with more than 25 years in Obstetrics & Gynaecology practice, specialises in reproductive endocrinology, subfertility, and polycystic ovarian syndrome.
He has contributed significantly to the understanding and treatment of male/female infertility. This work has led to deeper understanding on how androgen receptor mutations and polymorphisms cause sexual reversal in XY individuals and low sperm counts in subfertile males.
One of Singapore's leading medical researchers, he has won numerous awards. He authored/co-authored more than 200 papers, patents and abstracts. Currently, he leads a Consortium for Botanical Drug Development, a multi-disciplinary group that studies and develops drugs of herbal origin to pharmaceutical standards. He received a Ministerial Citation for his outstanding contribution to research on the genetics of human fertility by the National Science and Technology Board in 1999; and the Clinician-Scientist Investigator Award by the Singapore Biomedical Research Council in 2005.