Previous research has studied the link between epigenetics and IVF, but the results have been inconsistent. One reason for this is that fertility treatment is often associated with common risk factors, aside from the IVF technology itself, such as being older mums or having twins or triplets, which are more likely to be delivered prematurely and have a lower birth weight.
A new study has been published on risks to children conceived via IVF. According to the researchers at King’s College London and Murdoch Children’s Research Institute, fears of commonly assumed risks are “largely unfounded” and the long-term health effects of IVF are still relatively unknown.
In their study, scientists compared the epigenetic changes that occurred as a result of IVF and the natural conception of newborn twins. At the same time, it was the pairs of twins that were considered in order to exclude epigenetic differences that are possible with a single and multiple pregnancy.
Most of the previous epigenetic studies in IVF focused on selected regions of the genome that regulate genes known to cause developmental disorders due to epigenetic alterations, but scientists investigated the entire genome to ask if there were differences in genes that had not been previously implicated in epigenetic disorders.
They found no major epigenetic differences in IVF-conceived twins, but did find epigenetic changes with small impacts. Two genes related to male and female infertility showed small but significant differences in IVF-conceived twins, which suggests that the newborn twin epigenetic profile may contain markers of parental infertility, to a small extent. But it is unclear if the small changes were a result of infertility or the IVF treatment itself.
Twins provide a natural unique study design that allows to separate the importance of genes and environment on human traits. Environment exposures can be shared by both twins in a pair, for example in the womb, or exposures can also be specific to each twin. Using this twin-based approach scientists found that environmental factors specific to each twin were most likely to influence the top IVF-associated epigenetic changes. One explanation for these results could be that the IVF procedure introduces slight variability in epigenetic marks.
Epigenetic differences have been identified in common chronic diseases such as cancer, psychiatric disorders and diabetes. Scientists found no such major epigenetic differences in babies conceived by IVF, although future studies are needed to see if the small epigenetic changes scientists observed remain over time. Study results are reassuring for parents who used IVF and children conceived by IVF as the research suggests that IVF technology has little impact on epigenetic changes, and potentially future health.
Based on The Conversation