A process used to decide which IVF embryos should be implanted and which should be destroyed could be reducing the chance of a successful pregnancy, scientists say.
Pre-implantation genetic screening (PGS) is a method used to screen embryos produced in IVF fertility treatment to ensure that the ‘best’ ones are implanted into a woman’s womb. The others are deliberately destroyed.
PGS involves removing cells from embryos and running tests on them.
Doctors can use the same process to select embryos to become so-called ‘saviour siblings’. This is the controversial practice where a child is created so that its tissue can be used to treat a sick brother or sister.
The creation of ‘saviour siblings’ was recently approved by MPs when they voted on the Human Fertilisation and Embryology Bill.
But now research has shown that PGS can actually reduce pregnancy and birth rates in older women receiving fertility treatment, possibly because the embryos are damaged when cells are removed for tests.
The research has led the British Fertility Society to publish new guidance on PGS, discouraging doctors from using it except under limited circumstances.
A spokesman for the BFS, Professor Richard Anderson, from the Centre for Reproductive Biology at the University of Edinburgh, said: “There is now an urgent need for further research on PGS to assess both its safety and efficiency in treating a range of patients.”