Women undergoing IVF may be increasing the chances of stroke or heart failure IVF patients who never have a baby are at a 19 per cent higher risk, study claims Researchers looked at women who were given hormone injections as part of IVF Found the drugs may cause damage to women’s hearts by raising the risk of clots Women who have unsuccessful IVF are a fifth more likely to suffer heart disease, which may be caused by powerful fertility drugs, a study has shown. The drugs could be dangerously affecting blood pressure and raising the risk of blood clots. Women in Britain, some of whom undergo more than ten IVF cycles, may be increasing their susceptibility to stroke or heart failure each time. IVF patients who never have a baby are at a 19 per cent higher risk of cardiovascular disease than IVF patients who do have babies, the study found. Researchers looked at women who were given gonadotropins – hormone injections that stimulate the ovaries to produce more than the usual one egg a month. These drugs may cause damage to women’s hearts by raising the risk of clots or changing how the body controls blood pressure. Women who do become pregnant through IVF are less likely to take these drugs in the future, lowering their risk of heart problems, the researchers suggested. Overstimulated ovaries release chemicals into the bloodstream that can make blood vessels more leaky. This could cause remaining blood in the vessels to thicken, making clots more likely. However, it may simply be the case that the genes that make women infertile also make them predisposed to heart problems. Lead researcher Dr Jacob Udell, a cardiologist at the Institute for Clinical Evaluative Sciences in Canada, said the findings could be the ‘tip of the iceberg’. He said: ‘We have noticed, caring for these patients for a long time, that fertility drug treatment can cause short-term complications, such as high blood pressure and diabetes during pregnancy. ‘I recently started worrying that there may be some longer term consequences.’ He believes a predisposition to heart problems is the most likely cause, but added: ‘The alternative explanation is that repeated cycles of these powerful medications may somehow lead to premature heart disease.’ The latest figures show that 52,288 women in Britain had 67,708 rounds of IVF in 2014. The study looked at everyone under 50 who had gonadotropin fertility treatment in Ontario over two decades, totalling 28,442 women. The women followed were in their late forties on average by the end of the study After a decade they found that patients whose treatment had been unsuccessful had a 19 per cent increased risk of cardiovascular problems, including stroke, thrombosis and heart failure. The researchers stressed that only about ten in 1,000 suffered heart problems after failed IVF, compared with six in 1,000 for those who had successful treatment. But the link, if proved, could be significant for many people – IVF did not work for two-thirds of the women studied, even after an average of three cycles. Many British women, who can have up to three cycles of IVF on the NHS, could be raising their risk of heart problems by paying for more. Although ‘mild’ IVF is available with fewer or no drugs, most are likely to take fertility drugs to produce as many eggs as possible. The drugs increase the risk of ovarian hyperstimulation, which can cause blood clots, and could raise blood pressure by affecting the renin-angiotensin system. Dr Udell said: ‘There may be many more issues to come in the years ahead that we will have to follow up to have a better sense of whether we are just finding the tip of the iceberg’. Co-author Dr Donald Redelmeier said: ‘We don’t want to alarm women who undergo fertility therapy – we are instead suggesting that as women age, they should stay mindful of their health.’ Source
