Two recent studies have shown that the incidence of birth defects and long-term circulatory problems is much higher among children conceived with IVF.
A group from Nanjing Medical University in China did a meta-analysis of all studies of children conceived through IVF and ICSI and found that they are at “significantly increased risk for birth defects”. The research, published in the journal Fertility and Sterility, indicated that these children had a 37% higher risk of a birth defect across a range of body systems.
According to the Centers for Disease Control and Prevention, major birth defects occur in about 3 out of every 100 babies born in the US. This data indicates that the corresponding figure for IVF babies is 4 in every 100.
However, the reasons for this are far from clear. There are three main theories: people who have trouble conceiving also tend to have babies with birth defects. The IVF drugs, culture media and techniques themselves could cause the defects. Or finally, there seem to be more defects simply because the children are more closely observed.
None of this is news. It merely “confirms what most people accepted anyway, that, yes, there is an increased risk in congenital abnormality associated with assisted reproductive technology," William Buckett, a professor at McGill University, told Reuters.
The long-term effects of IVF are even less clear. But a provocative study in the journal Circulation suggests that there may be significant circulatory problems in later life. Sixty-five 65 12-year-olds were examined. The researchers found “significant vascular dysfunction” – “adverse changes in both the systemic and pulmonary circulations, including structural and functional alterations”. Some of these are associated with higher risk of heart disease. “This problem does not appear to be related to parental factors but to the ART procedure itself,” the authors, from the Swiss Cardiovascular Center Bern, state emphatically.
In an associated editorial, David Celermajer, of Sydney University Medical School, says that this is a small but significant study. However, he says, IVF is here to stay. Hence, “the urgent need for us to understand the possible adverse late outcomes of ART and to focus on finding possible technical changes to the in vitro procedures that might ameliorate or reverse any potentially harmful health consequences.”