Dr. Ku specializes in reproductive endocrinology and has particular interest in the field of polycystic ovarian syndrome, infertility, endometriosis, menopause and antiaging research. He is also actively working in the field of human embryonic stem cell research, especially for differentiation of cardiac mesoderm precursor cells, and is a member of Steering Committee of Institute of Reproductive Medicine and Population, Medical Research Center. He is serving as Secretary General to the Korean Society of Gynecologic Endocrinology (KOSGE) and Korean Society of Reproductive Medicine (KSRM). He has published numerous articles and chapters domestically and internationally, and has been serving as reviewer of Journal of KSRM.