Fertility treatment used to help infertile men become fathers can raise the risk of birth defects in babies, according to a new study.
Research on more than 300,000 babies found those born using Intracytoplasmic sperm injection (ICSI) had a significantly higher risk of developing abnormalities than those conceived naturally.
Researchers linked a census of more than 6,100 births that occurred as a result of fertility treatment in South Australia to a registry of more than 300,000 births and 18,000 birth defects.
The report by the University of Adelaide published in the New England Journal of Medicine shows that on average defects were present in 8.3 per cent of pregnancies that involved fertility treatment compared to 5.8 per cent of those conceived naturally.
According to the study, in vitro fertilisation (IVF) posed the least risk to women opting for assisted conception, with defects occurring in only 7.2 per cent of pregnancies.
ICSI is primarily used for male fertility problems and this risk is decreased using frozen eggs, according to the study’s lead author, Associate Professor Michael Davies.
‘I don’t want to scare people,’ he said because the majority of babies were born healthy.
‘But this may be due to developmentally compromised embryos failing to survive the freeze/thaw process,’ he said.
‘While assisted reproductive technologies are associated with an increased risk of major birth defects overall, we found significant differences in risk between available treatments.’
More than 3.7 million babies are born each year through assisted reproduction.
Methods include everything from drugs to coax the ovaries to make eggs to artificial insemination and IVF. Fertility treatments account for about four per cent of births in Australia and as many as eight per cent of them in Denmark, where costs are widely covered, Davies said.
In the United States, more than 60,000 babies were born in 2009 from 146,000 IVF attempts. About three-quarters of them used ICSI, or intracytoplasmic sperm injection.
ICSI was developed because of male infertility. But half the time, it was not done for that reason but to improve the odds that at least some embryos will be created from an IVF attempt.