"I am certain that in the long term we will be able to help everyone," he told a news conference.
Around three out of every four couples facing infertility can benefit from current treatments. Intracytoplasmic sperm injection (ICSI), in which a single sperm is injected into the egg, has enabled infertile men to have children and embryonic screening and other techniques have improved success rates.
Helping men who produce no sperm and women without eggs will be the remaining challenge but stem cells, which are able to grow into all cells and tissues in the body, could be the answer.
"In future we'll be able to take cells and reconstruct the equivalent of sperm and eggs," said Trounson, of Australia's Monash Institute of Reproduction and Development. "It is theoretically possible," he added. But although animal experiments have shown promise, Trounson said it would take at least 10 years or more and need much more basic research first.
Stem cells hold the promise of treating a range of medical conditions but their use is controversial because although they are found in adult tissue, the most flexible stem cells come from early embryos left over from In Vitro Fertilization (IVF) fertility treatment.
Professor Roger Pedersen, of Britain's University of Cambridge, compared a stem cell to the Rosetta Stone, which helped researchers to decipher hieroglyphics.
"It enables us to understand the language by which cells talk to each other, to understand how to change the fate of cells in our own bodies and how to get better function out of (our own) stem cells," he said.
"This is all a legacy of 25 years of IVF because every single embryo that can be studied is a result of the in-vitro fertilization procedure."