A panel of fertility experts has analysed medical data on children conceived by in IVF, and found that overall, they are no more likely to have major health problems than naturally conceived children. They found no evidence to suggest that IVF increases the incidence of major birth defects, cancers or problems in psychological or emotional development. However, it was found that IVF might have a 'negative impact' on some children during birth. The study also confirmed earlier work linking IVF to a slightly increased risk of some rare genetic conditions. The panel, which reviewed 169 published studies, reported its findings at the annual meeting of the American Society for Reproductive Medicine in Philadelphia on Tuesday.
The panel found that twins born after IVF were at no more risk of health problems than twins conceived naturally. But, they said, with singleton IVF babies, there was more likelihood of a premature birth or a clinically low birth weight. It is known that this can sometimes cause health and developmental problems as a child grows up. The panel also found that IVF babies are also twice as likely to die during birth, or soon after. The evidence also suggested that IVF babies are at greater risk of being born with some rare disorders caused by a failure of 'genetic imprinting', such as Beckwith-Wiedemann syndrome. Some scientists think this may be due to the conditions in which embryos are kept in the laboratory, before being transferred to the womb.
The panel estimated that about one per cent of babies born in the US are conceived using IVF, and while there has always been some concern that IVF might affect aspects of children's health, previous studies examining IVF children have not borne this out. The panel members said they did not know exactly what caused birth problems to occur in some IVF children - it may be the IVF process itself, they said, as it cannot exactly mirror 'normal' fertilisation. But, they said, it is also possible that infertile parents may pass on problems to their children, or infertile mothers may be more likely to have problems during pregnancy. Panel member Marcelle Cedars, from the University of California, San Francisco, said 'I think these women are different'.
The panel's next task is to make recommendations for those working in IVF as to how to find out what causes health problems in IVF children at birth, as well as how to avoid the problems in the future. They advocate larger, longer and more detailed studies of children born from IVF, which might reveal, 'particular groups of parents who are at greater risk of health problems, and who could be given additional testing or support'. In addition, they want research to be conducted on how growth solutions used to nurture embryos in labs might affect children's well-being.
Sources and References
In vitro fertilization is found safe to children, with exceptions
Child health appears unaffected by IVF