International Federation of Gynecology and Obstetrics

There are simple aspects of infertility which are not being addressed, according to Comment on Reproductive Ethics (Core).

The comments were made after US scientists discovered a technique which could convert human stem cells into eggs and sperm.

Researchers at the US National Institute of Health say the discovery could also allow scientists to discover the causes of infertility and birth defects.

However, Josephine Quintavalle, director of Core, said some of the causes of infertility are linked to age and lifestyle.

She said: "One of the principle considerations in terms of healthy offspring is the age of the mother. Another area is lifestyle issues such as smoking.

"Over-eating or under-eating, obesity and anorexia can [also] cause infertility."

Ms Quintavalle added that there should also be some educational initiatives to combat the problem.

She claimed that "some very basic education" of when is the best time to have children is needed, in terms of womens' body mass and general health.