Future fertility treatment could allow parents and doctors to have a preview of which eggs will make the most viable embryos.
That is the main conclusion from a report from Brown University which managed to extract genetic material from a human egg cell without harming it.
Scientists used polar bodies picked from the cell to reveal the genes that would be expressed within the gamete.
These polar bodies are perfect as a "natural cytoplasmic biopsy", said study co-author Sandra Carson, professor of obstetrics and gynaecology at the Warren Alpert Medical School of Brown University.
Researchers found that 90 per cent of the genes expressed in the egg cells were also contained in the polar body – formed when an egg cell disposes of unneeded chromosomes.
The Human Fertilisation and Embryology Authority has restricted the number of embryos used in IVF to two for women under 40 due to the risk of multiple births.