20 May 2013
ByAppeared in BioNews 705
The method involves taking thousands of pictures of embryos to track their development before they are implanted in the womb. The clinic, one of the few in the UK to offer this technique, claims that this can boost IVF success by more than 50 percent.
IVF is extremely costly, and typically has a low chance of success. One of the most common causes of failed IVF is aneuploidy, when implanted embryos have too many or too few chromosomes. Currently, the only way to check an embryo for chromosomal abnormalities is to remove a cell, which then undergoes genetic screening. This procedure costs about £2,500, and the act of removing a cell can cause developmental problems further down the line.
Now, scientists at CARE fertility clinic in Nottingham, UK, have developed an alternative approach based on time-lapse imaging. Fertilised eggs are placed in an incubator, which is hooked up to a video system capable of capturing thousands of images documenting the embryos' development from conception to the blastocyst stage (70 to 100 cells). 'This is almost like having the embryo in the womb with a camera on them', explains CARE's managing director Dr Simon Fishel.
Studying these images reveals certain trends. The team found, for example, that abnormal embryos took around six hours longer to form a blastocyst than healthy ones. They came up with an algorithm for predicting embryonic health, and the likelihood that a particular embryo would lead to a successful birth.
'In the 35 years I have been in this field this is probably the most exciting and significant development that can be of value to all patients seeking IVF', Dr Fishel told the BBC. The clinic claims the new technique could increase the success rate for IVF treatment to 78 percent - over three times the UK national average.
They investigated 88 embryos from 69 couples visiting the clinic, using the time-lapse technology to classify embryos as having high, medium or low risk of chromosomal defects. Eleven babies were born from the low risk group (61 percent success rate) and five from the medium risk group (19 percent success rate). No embryos from the high-risk group successfully implanted.
Only about a dozen IVF clinics in the UK offer the £750 imaging service, but CARE researchers say that if the technique were to be adopted by the NHS, it could boost success rates and reduce the costs of IVF.
But others are more cautious. Dr Allan Pacey, chair of the British Fertility Society, said: 'All too often developments in IVF are trumpeted as advances when they remain unproven. In this case, whilst this is a good piece of science, before we splash this on the front page it should be subject to full randomised control trials'.
The study was published in the journal Reproductive BioMedicine Online.