From artificial insemination to 'artificial' sperm itself, developed from stem cells.
Yes, British scientists have developed human sperm in the laboratory. The Newcastle University work centres on stem cells - 'blank' cells with the ability to turn into other cell types.
Biologist Karim Nayernia created a cocktail of chemicals and vitamins that turned human stem cells into sperm, the journal Stem Cells and Development reports.
Viewed through a microscope, they have heads and tails and swim like normal sperm, and Professor Nayernia is 'convinced' they would be capable of fertilising eggs and creating babies.
He has more safety checks to carry out but plans to apply for permission to use some of the artificial sperm to fertilise eggs for research purposes.
The stem cells used were taken from embryos in the first days of life but the professor hopes to repeat his success with skin cells taken from a man's arm. These would first be exposed to a mixture that wound back their biological clocks to embryonic stem cell state, before being transformed into sperm.
Using IVF techniques, the artificial sperm could be injected into eggs, allowing men who do not produce sperm to father children of their own.
The breakthrough in stem cell science offers a potential cure for male infertility and could be used in IVF clinics in as little as five years.
Professor Nayernia said: 'This is an important development as it will allow researchers to study in detail how sperm forms and lead to a better understanding of infertility in men - why it happens and what is causing it.
'Male infertility is a growing problem and no one knows why. We'll be able to study the effects of pollution and nutrition in the lab.'
Professor John Burn, professor of clinical genetics at Newcastle University, believes stem cells will be a treatment for all types of diseases.
"The same approach could ultimately allow us to control the development of liver cells, heart cells or brain cells...and make treatments for virtually any tissue that is damaged or diseased."
Dr Allan Pacey, senior lecturer in andrology at the University of Sheffield and honorary secretary of the British Fertility Society, said: "To be able to make functional sperm under controlled conditions in the laboratory will be very useful to study the basic biology of sperm production.
"There are currently many things we don't know about how sperm are formed let alone why it sometimes goes wrong and leads to infertility in some men.
But he added: "It is more difficult to say whether artificial sperm produced this way could ultimately be used as a new treatment for male infertility. There are many technical, ethical and safety issues to be confronted before this could even be considered."
Professor Harry Moore, professor of reproductive biology at the University of Sheffield, said: "These processes in the test-tube are far from perfect as the mice that were born by this process were abnormal.
"We therefore have to be very cautious about using such techniques in therapies to treat men or women who are infertile due to a lack of germ stem cells until all safety aspects are resolved. This may take many years."
Anna Smajdor, a researcher in medical ethics at Imperial College London, said: "The creation of viable sperm outside the body is a hugely significant breakthrough and offers great potential for stem cell research and fertility treatments.
"However, sperm and eggs play a unique role in our understanding of kinship and parenthood, and being able to create these cells in the laboratory will pose a serious conceptual challenge for our society."
Prof. Nayernia also acknowledged that the ethical issues involved, like the technique could be applied to skin cells taken from men who have been dead for many years, allowing them to 'father' children.
He said: 'This is the Jurassic Park scenario. In theory this would be possible but human reproduction is not a purely biological process. We have to think of the psychological, social and ethical considerations.'
The Newcastle team tried to create sperm from stem cells from female embryos but failed - suggesting that men will always have an important role in the creation of life.
But, in time, it may be possible to create eggs from a woman's stem cells, raising the possibility of artificial eggs and sperm being combined to create children through entirely artificial means.
Some expressed horror at the prospect of creating human life. Josephine Quintavalle, of campaign group Comment on Reproductive Ethics, said: 'To take a viable human embryo and destroy it in a bid to create dodgy sperm to create a not-so-healthy embryo is experimentation for experimentation's sake.
'Infertility is an issue we have to address but this is not an ethical solution. If the solution involves the sacrifice of human life, then it should be apparent to anyone that it is unacceptable.'