Scientists have claimed they have found a way for women to have babies without men by creating artificial sperm.
The team from China claim they created healthy mouse babies by just injecting laboratory-made sperm into eggs to produce mouse offspring.
The scientists claim their stem cell technique could pave the way for new treatments for male fertility.
The mouse cells produced were technically “spermatids” – undeveloped sperm that lack tails and cannot swim.
Yet when they were injected into mouse eggs, mimicking a common IVF technique called Icsi (intracytoplasmic sperm injection), they delivered viable embryos and healthy, fertile babies.
In the UK, using spermatids in the same way to produce a pregnancy would be illegal.
Dr Jiahao Sha, from Nanjing Medical University, who co-led the research, published the results in the peer-reviewed journal Cell Stem Cell.
“If proven to be safe and effective in humans, our platform could potentially generate fully functional sperm for artificial insemination or in-vitro fertilisation techniques.
Because currently available treatments do not work for many couples, we hope that our approach could substantially improve success rates for male infertility.”
Infertility affects around 15% of couples and can be traced to the man in about a third of cases.
A major cause of male infertility is the failure of pre-cursor cells in the testes to undergo a special type of cell division called meiosis.
Scientists in the UK praised the “mammoth” achievement of their Chinese colleagues but said there were still many obstacles to be overcome before sperm-like cells grown in the laboratory could be of use to infertile men.