IVF temporarily changes babies' epigenetics

A new study has found that children born from assisted reproductive technologies have different epigenetic patterns to those born through natural conception - but that these differences vanish by adulthood.

The study led by researchers at the Murdoch Children's Research Institute (MCRI) in Melbourne, Australia investigated levels of DNA methylation - an epigenetic modification which can affect the activity of certain genes without changing the actual DNA sequence. 

'Given the interventions associated with assisted reproduction technology at the time of conception, there are concerns that epigenetic changes may be taking place, silencing important genes and resulting in a heightened risk of health problems,' said Professor Jane Halliday at MCRI, on the rationale behind the study.

To test this, the study looked at 75 people conceived naturally and 158 people conceived with two different assisted reproductive therapies - IVF and gamete intrafallopian transfer (GIFT), where fertilisation takes place in the woman's fallopian tube. 

Looking at blood taken from newborn heel prick blood tests, the study found that babies born via assisted reproductive treatments did indeed have different epigenetic patterns than those born from natural conception.

These changes were similar in children born from either IVF or GIFT, leading the authors to speculate that ovarian stimulation - which is involved in both procedures - may be the cause of the epigenetic changes, or that perhaps infertility itself is. 

However, unlike other work in this area, this study also followed the children as they developed and revealed that the majority of epigenetic changes seen at birth had resolved by the time the children reached 22-35 years old.

Dr Boris Novakovic, also at MCRI and first author, explained: 'Previous studies have found some epigenetic changes in embryos grown in labs. However, no study has looked for these changes in the same individuals at birth and adulthood as we have done.'

Importantly, the authors also state that their work does not reveal any direct evidence that the epigenetic differences initially seen between the groups actually impact on development or health.

The authors are now keen to perform further studies to investigate when the epigenetics changes begin to disappear, what aspect of assisted reproductive technologies influence a person's epigenetic profile, and the long-term health implications.

The study was published in Nature Communications.