He showed that exogenous FSH has a positive feedback on the release of endogenous FSH. That is the basic science behind the use of exogenous gonadotropins (Pergonal, Metrodin and others) for extra follicular development, in infertility management and IVF cycles. Currently his area of research is in embryo culture techniques and implantation failure.
He pioneered the IVF program in Nigeria in 1984 and his team successfully delivered the first test tube baby in Africa in 1986. He has over twenty five years in the management of difficult cases of infertility, twenty eight years experience in IVF and fifteen years experience with ICSI and new assisted reproduction technologies
He was appointed Consultant reproductive Endocrinologist to Lagos University Teaching Hospital in 1980 and Professor of Anatomy in 1983, making him the youngest appointed professor in Nigeria at the age of thirty two. He was reproductive Endocrinologist in the Department of Obstetrics and Gynecology in Omaha in 1978.
He obtained a joint appointment with the departments of Anatomy and Obstetrics and Gynecology at the University of Illinois at Chicago(UIC) at Professorial level. He established two IVF programs for the University in 1996 and became the pioneer director of the University based IVF program at Chicago in 1996. It is currently one of the best IVF centres in the US. He has established collaborations with several infertility centres internationally. Professor Ashiru obtained the licentiate of the American Board of Bioanalysis in High Complexity Laboratory Director HCLD (ABB) in 1997.(The American regulatory and licensing body for assisted reproduction technologies).
He is the author of Want a Baby, a book on the causes, management and treatment of infertility