As the use of IVF expands to a wider range of fertility problems, experts warn that the risks could outweigh the benefits.
IVF was developed for women with fallopian tube disorders and severe male infertility, but in recent years it has been applied to wider conditions, including unexplained infertility, writes Dr Esme Kamphuis and colleagues including the University of Aberdeen's Professor Siladitya Bhattacharya on bmj.com today.
For instance, in the UK, the proportion of IVF cycles for tubal problems fell from 19% to 12% between 2000 and 2011, although the number of cycles remained around 7,000. The figures for unexplained infertility tripled from just over 6,000 to over 19,500 cycles.
They argue that the evidence underpinning the use of IVF for some of these newer indications is weak, and they question whether IVF is equally effective in these conditions and if the long term health risks for IVF children can be justified.
Unexplained infertility accounts for up to 30% of all couples presenting for IVF, many of whom will conceive when not treated immediately. Indeed studies have shown considerable natural conception rates in couples with no obvious cause of infertility for two to three years.
Yet the authors point out that much IVF research often does not mention how long couples have been trying to conceive. And national fertility registries in many countries do not collect data on duration of infertility.
Extended use of IVF also increases the risk of harm, they add. Multiple pregnancies are associated with complications for mothers and infants, and even single babies born through IVF have been shown to have worse outcomes than those conceived naturally.
Concern has also been raised about the long term health of children born through IVF. Otherwise healthy children conceived by IVF may have higher blood pressure, body fat distribution (adiposity), glucose levels, and more generalised vascular dysfunction than children conceived naturally.
“Until these concerns are resolved, there should be caution about using IVF in couples when the benefit is uncertain or the chances of natural conception are still reasonable,” say the authors.
They believe a lack of will to question the perceived success of IVF is preventing progress, and argue that the paucity of quality evidence on who should have IVF and when should be addressed.
“As a society, we face a choice,” they conclude. “We can continue to offer early, non-evidence based access to IVF to couples with fertility problems or follow a more challenging path to prove interventions are effective and safe and to optimize the IVF procedure. We owe it to all subfertile couples and their potential children to use IVF judiciously and to ensure that we are first doing no harm.”