The first human egg cells that have been grown entirely in the laboratory from stem cells could be fertilised later this year in a development that will revolutionise fertility treatment and might even lead to a reversal of the menopause in older women. Scientists are about to request a licence from the UK fertility watchdog to fertilise the eggs as part of a series of tests to generate an unlimited supply of human eggs, a breakthrough that could help infertile women to have babies as well as making women as fertile in later life as men.
Producing human eggs from stem cells would also open up the possibility of replenishing the ovaries of older women so that they do not suffer the age-related health problems associated with the menopause, from osteoporosis to heart disease. Some scientists are even suggesting the possibility of producing an “elixir of youth” for women, where the menopause is eradicated and older women will retain the health they enjoyed when younger.
Researchers at Edinburgh University are working with a team from Harvard Medical School in Boston to be the first in the world to produce mature human eggs from stem cells isolated from human ovarian tissue.
Until now, it has only been possible to isolate a relatively small number of mature human egg cells directly from the ovaries of women who have been stimulated with hormones. This technical limitation has led to an acute shortage of human eggs, or “oocycts”, for IVF treatment as well as scientific research. The scientists want to fertilise the laboratory-grown egg cells with human sperm to prove that they are viable. Any resulting embryos will be studied for up to 14 days – the legal limit – to see if they are normal.
These early embryos will not be transplanted into a woman’s womb because they will be deemed experimental material, but will either be frozen or allowed to perish.