A leading UK fertility expert is warning that infertility is set to double in Europe over the next decade and could threaten Europe's population.
According to Professor Bill Ledger from Sheffield University, one in seven couples now has trouble conceiving naturally, and this figure is set to rise to one in three.
At a European fertility conference Ledger said that women should be offered career breaks so they could have children younger, when they are more fertile.
He also explained that obesity and sex infections were contributing to increasing infertility, and the sustainability of the population of Europe is at risk because there are too few children being born.
Apparently the incidence of chlamydia, a sexually transmitted infection which carries a risk of infertility, has doubled over the last decade, and to date 6% of girls under the age of 19 are classed as obese.
An obese child is almost certainly destined to become an obese adult, and many women who are overweight do not ovulate efficiently.
He warns that the rise in sexually transmitted infections in young teenagers was likely to cause blocked fallopian tubes in some.
The problem does not just lie with women, as both the quality and quantity of sperm appeared to be in decline indicating a potential rise in male infertility.
Professor Ledger says the youth of today will become tomorrow's patients in infertility clinics.
Inflexible working hours and financial and career aspirations mean many women are putting off having a family until they are in their late 30s and early 40s, he said.