The first study to break down IVF failure rates for each treatment stage across different age groups has found that after the age of 37 the chance of a woman becoming pregnant through IVF rapidly declines.
Researchers from Aberdeen University found that the likelihood of a live birth through IVF fell steadily from 25 percent in the 35-to-37 age group to two percent in the 45-to-50 age group.
Professor Siladitya Bhattacharya, who led the research, said: 'IVF comprises a number of key steps, each of which has to be successfully achieved before the next stage can be attempted. We found that age impacted on every single hurdle that has to be overcome during the emotional rollercoaster that is IVF'.
Researchers studied data from 121,744 women from across the UK who had their first cycle of IVF between 2000 and 2007 using their own eggs, including data from cycles using intracytoplasmic sperm injection (ICSI).
They found that during the earliest phase of treatment women who had ICSI had a lower chance of failure than those using conventional IVF, but this advantage was lost once embryos were created. In other words, the data suggest that ICSI embryos do not have any greater chance of implanting.
The study, published in the journal PLOS ONE, also shows that even after becoming pregnant, 38- and 39-year-old women were 43 percent more likely to miscarry than women aged 18-to-34.
Professor Bhattacharya said he hoped the study would provide a more accurate and dynamic way of predicting a couple's chances of treatment failure as they negotiate each step of IVF'.