Scientists grow first human embryo

Researchers in University of Edinburgh says human eggs have been grown in the laboratory for the first time.
According to the team,it is a technique that could lead to new ways of preserving the fertility of children having cancer treatment.
It also create an opportunity to explore how human eggs develop, much of which remains a mystery to science.
Experts claimed it was an exciting breakthrough, but more work was needed before it could be used clinically.
Women are born with immature eggs in their ovaries that can only develop fully after puberty.
It is a long time work, but scientists can now grow eggs to maturity outside of the ovary.
It requires carefully controlling laboratory conditions including oxygen levels, hormones, proteins that simulate growth and the medium in which the eggs are cultured.
Opportunity for cancer patients.
Chemotherapy and radiotherapy risks making you sterile.
Women can freeze matured eggs or embryos if they are fertilised with a partner's sperm, before starting treatment - but this is not possible for girls with childhood cancers.
At the moment they can have ovarian tissue frozen before treatment, which is then put back in to mature years later if the patient wants children of their own.
But if there are any abnormalities in the frozen sample then doctors will think it is too risky.
Being able to make eggs in the lab would be a safer option for those patients.