Researchers from the University of Western Australia have published a study suggesting IVF effectiveness could be improved by undergoing more cycles.
The effectiveness of IVF treatment was assessed by retrospective analysis of IVF success rates in Western Australia. It was found that, between 1993 and 2002, IVF was 47 percent effective overall in women who received an average of three IVF cycles. It was more effective in younger women, with 58 percent of women in their twenties having success, compared to 22 percent of 40-44 year olds.
The group noted that the cumulative probability of IVF success increased with each successive cycle for at least the first five cycles. Lead author Louise Stewart, researcher at the School of Population Health, stated: 'The results of this study suggest that IVF has the potential to be more effective if women, especially those over 35, are able to undertake more than the usual two to three cycles'.
Currently in the UK, the 2004 National Institute for Health and Clinical Excellence (NICE) guidelines recommend the NHS provide three full IVF cycles to eligible patients. However, these guidelines are not binding and there is significant variability in practice between Primary Care Trusts responsible for controlling fertility services on the NHS.
An additional observation made in this report was that a significant number of women went on to have IVF treatment-independent births after they stopped IVF treatment. Specifically, 21 percent of women in their twenties and 11 percent of women in their early forties.
Fertility expert Dr Mitchell Rosen of the University of California, San Francisco, who was not involved in the study, told Reuters Health: 'It is pretty obvious that the number of cycles that you do adds to the likelihood of success, but it gets smaller every time. At some point the psychological side effects and the cost become prohibitive'.
The study was published in the journal Fertility and Sterility.