Children can now trace their biological parents when they are 18
The limit on the number of pregnancies that can be created from the sperm of a single donor should be raised, fertility experts suggest.
Dr Mark Hamilton and Dr Allan Pacey, of the British Fertility Society (BFS), said the UK was struggling with a serious shortage of sperm donors.
Writing in the British Medical Journal, they said radical reform of the current system was needed.
They blamed removal of donor anonymity in 2005 for the donor shortage.
Children can now trace their biological parents when they are 18.
Overall, the number of sperm donors has fallen by 40% in 15 years.
The experts warned that many fertility clinics have long waiting lists, or have been forced to stop providing services altogether.
At present around 4,000 UK patients request donor sperm each year.
Under UK regulations, the maximum number of families that can use sperm from the same donor is 10.
This is to reduce the risk that children born from sperm donated by the same man will have children together in later life.
Therefore, assuming not all donors would consent to their sperm being used in 10 pregnancies, a minimum of 500 new donors are needed every year to meet demand.
But in 2006 there were only 307 new registrations.
Dr Hamilton and Dr Pacey argue that the current limit is arbitrary and not evidence based - and a more flexible approach is needed.
They point out that the size of the UK population is enough for a large safety margin to already exist.
In the Netherlands, which has a smaller population than the UK, the upper limit is 25 offspring per donor, while in France it is five.
The BFS doctors are also touting a possible reorganisation of recruitment services, with donors handled by large regional centres, while smaller local centres deal with recipients.
Currently, up to 35% of potential donors are lost after their first enquiry and never assessed.
The Dr Hamilton and Dr Pacey said it was vital to try to reduce this number by making services more accessible and efficient.
One possibility would be to set up sperm sharing schemes in which fertile men could donate sperm to partly fund IVF for their partners.
Dr Pacey, who is based at the University of Sheffield, said: "Many clinics have really struggled over the past few years to recruit enough donors to treat their patients and this has caused a lot of anguish amongst both patients and professionals alike."
However, the doctors said safety concerns ruled out raising the age limit of sperm donors from the present 40 years, or lowering the acceptable levels of semen quality.
Walter Merricks, of the Donor Conception Network agreed that reform was needed.
He said: "The current shortage means that many of those seeking donor insemination treatment are going to clinics overseas.
"The vast majority of our members would far prefer to be treated locally with a UK donor under the protections afforded by Human Fertilisation and Embryology Authority (HFEA)regulation."
A Department of Health spokesperson said it would consider the BFS recommendations carefully.
The spokesperson denied the removal of anonymity had led to a drop in donor numbers, but agreed that more were needed.
An HFEA spokesperson said the limit on use of donor sperm was under review.