For the first time ever, scientists have succeeded in growing human eggsfrom the earliest stages to full maturity in a laboratory.Before now, scientists had only succeeded in doing so with the eggs of mice,maturing those eggs to the stage where they produced living babies.They had also grown human eggs from a later stage of development.Scientists at two research hospitals in Edinburgh, Scotlandand the Center for Human Reproduction in New York completed this latest experiment.They published the results of their researchin the journal Molecular Human Reproduction in early February.They said this research could one day help in developing medicinesand new treatments for people who are unable to produce children.Normally, microscopic eggs developin the part of the female reproductive system called ovaries.However, this is the first time human eggs have been developedoutside the human body from their earliest stage to full maturity.Evelyn Telfer is a co-leader of the research.She told the Reuters news service,"Being able to fully develop human eggs in the could widen the scope of available fertility treatments.We are now working on optimizing the conditionsthat support egg development in this way and studying how healthy they are."Independent experts not directly involved in this work supported it by calling it important.But they also warned that there is much more to do before laboratory-grown human eggscould be safely made ready for reproduction with sperm.Ali Abbara is a medical expert at Imperial College London.He said this latest research suggests it may be possibleto fully combine human eggs and sperm outside the body in the future." the technology remains at an early stage," he added."And much more work is needed to make surethat the technique is safe and optimized before we ascertainwhether these eggs remain normal during the process,and can...form embryos that could lead to healthy babies."Darren Griffin is a genetics professor at Kent University in the United Kingdom.He called the work a surprising technical success.If success and safety rates were improved,it could help future cancer patientsreceiving chemotherapy treatment protect their fertility, said Griffin.It could also improve fertility treatments,and deepen scientific understanding of the biology of the earliest stages of human life.