Dr. Kumar graduated from University of Singapore in 1977 and worked in Singapore General Hospital (SGH), Tan Tock Seng Hospital (TTSH) and Kandang Kerbau Hospital (KKH) during his housemanship year. After completing National Service in the Singapore Armed Forces (SAF), he undertook his postgraduate training as a trainee in the University Department of Obstetrics & Gynaecology, KKH, and obtained his specialist degrees in 1984. He subsequently joined the Department of Obstetrics & Gynaecology, University of Singapore (later called National University of Singapore), as an academic staff member and continued his career as a Lecturer, Senior Lecturer and Associate Professor in the department from 1984 - 2003.

In 1987, he was awarded the Overseas Postgraduate Research Scholarship by the National Health and Medical Research Council (NHMRC) of Australia to pursue his PhD degree at Monash University , Melbourne , Australia . His thesis involved the study of the effects of exogenous gonadotrophins on oocyte maturation and subsequent fertility, using the goat-model.

Dr. Kumar has also undertaken sub-speciacility training in gynaecological hysteroscopy and laparoscopy at the Hysteroscopy Training Centre, Spaarne Hospital, Haarlem in the Netherlands, and at Polyclinique Gynecologie Obstetrique Medecine de la Reproduction, Universite Clermont Ferrand in France.

During his 20 year tenure with the Department of Obstetrics & Gynaecology, National University of Singapore (NUS) and National University Hospital (NUH), Dr. Kumar was actively involved in the teaching and training of undergraduate medical students and postgraduate doctors, and undertaking clinical and academic research, in addition to routine patient care and clinical work.

Dr. Kumar’s sub-speciality interest is in Reproductive Medicine, and he has been involved in the field of Subfertility and Assisted Reproductive Techniques (ART) since 1991. He was the Clinical Coordinator of the Subfertility and ART programs, and Head of the Division of Reproductive Medicine at the National University Hospital (NUH) from 1997-2001. He was also a member of the successful NUH team that produced the world's first babies born after transfer of zona-softened blastocysts in both stimulated and natural ART cycles. Dr. Kumar was also responsible for introducing professional counseling for couples undergoing ART treatment. He has also been actively involved in the teaching and training of post-graduate doctors in the clinical management of subfertility and ART, both locally and regionally. His research interests included the use of Natural Cycle IVF, GnRH-antagonists in ART and use of metformin in the management of hyperinsulinaemia in Polycystic Ovarian Syndrome (PCOS)-related subfertility.

Dr. Kumar is currently in private practice at Gleneagles Hospital, where he continues his sub-specialty interest in the management of subfertile couples. Apart from practising general obstetrics and gynaecology, his other clinical interests include management of Male Infertility, Male and Female Sexual Problems, Polycystic Ovarian Syndrome (PCOS) and Gynaecological Laparoscopy and Hysteroscopy (key-hole surgery). He continues to be invited to speak at both local and regional meetings and to conduct training workshops related to infertility and Assisted Reproductive Techniques (ART).