The head of a Midlands fertility clinic has called on the Government to do more to avoid a " fertility time bomb" by helping more couples start their own families.
Dr Gillian Lockwood spoke out as more than 400 children, parents and grandchildren celebrated Midland Fertility Services' 18th birthday over the weekend.
Last year 317 babies were born as a result of treatment at the clinic in Aldridge, Walsall.
However, Dr Lockwood said she had noticed the number of women over 35 being treated had trebled in the past decade. She believes that rising house prices and inadequate funding for NHS treatment is forcing couples to postpone parenthood until later in life.
Speaking during Saturday's party in Aldridge, Dr Lockwood said: "Today has been amazing, because now we're 18 and we've got several generations here now.
"Since Brett Rigby - our first baby - was born in 1988, we've helped bring about 3,500 babies into the world.
"However we have seen the number of women over 35 seeking treatment treble in the past ten years.
"If that trend continues, we will see a major decrease in women having children before 25, and that change is something politicians need to take notice of."
Last week a magazine poll revealed that fertility problems were soaring in Britain because couples are too unfit for pregnancy.
Aside from alcohol, smoking, poor diet and drugs, researchers found that women delaying motherhood - for various reasons - could affect their fertility.
In January, The Birmingham Post launched its Funded Fertility Treatment For All campaign, as former Health Secretary John Reid called on all primary care trusts to offer one full funded cycle of treatment to women under 40 who need it.
Dr Lockwood also fears if the trend continues, it could result in a depleting population and lead to a further pensions crisis.
She said: "In Europe, 1.5 babies are born per woman, and at that rate the population would be falling significantly, if not for immigration from other countries.
"We need to make it possible to have children, but there are so many factors conspiring against young couples they are putting off parenthood until later in life. This is one of the most important social issues today."