Since the first IVF baby was born some 40 years ago, more than 7 million people have been born as a result of assisted reproductive technologies (ART) such as IVF. Studies have shown that babies born after ART are more likely to be born prematurely and to weigh less at birth, and they have a slightly greater risk of birth defects. However, by the time they become adults, research has shown that they are just healthy as other people.
Genes are sensitive to the environment and can change how they function if they are exposed to sub-optimal conditions. Changes in genes in response to the environment are called epigenetic. Epigenetic changes can affect the health of the baby at birth and in adulthood.
There are many possible reasons why babies born after ART have worse health outcomes at birth than their spontaneously conceived peers. Possible explanations include the parents’ infertility, the hormone stimulation used in ART, and the early embryo’s exposures in the laboratory. Researchers have wondered if some of these things might cause epigenetic changes in the growing embryo.
In a world-first study, a team led by Professor Jane Halliday at the Murdoch Children’s Research Institute, recently found evidence of epigenetic changes in ART-conceived babies that could be linked to hormone stimulation or the parents’ infertility. But the team also found that these epigenetic changes largely resolved by the time the children reached adulthood, with no direct evidence they impacted on development or health.
As part of a follow-up study of the long-term health of people conceived with ART, the researchers studied the epigenomes of 159 people conceived through ART and 75 people conceived without ART. The participants, aged between 22 and 35, gave blood for their adult epigenomes to be analysed.
To study these adults’ epigenomes at birth, the researchers used blood that had been collected from them at birth. A few days after birth all babies in Australia have a pinprick puncture in one heel to collect a drop of blood on filter paper. The blood is tested for some rare conditions and then stored for future testing if needed.
Taken together with the finding that ART-conceived people are just healthy in adulthood as other people1, the finding that epigenetic changes at birth disappear over time2 is reassuring for people born after ART, their parents, and people who might use ART in future.
The most recent follow-up study was funded by the National Health and Medical Research Council. Melbourne IVF and Monash IVF supported the study by providing small grants to initiate it, and they assisted with locating and recruiting participants
You can read more about the research here.
1 Halliday J, Lewis S, Kennedy J, Burgner DP, Juonala M, Hammarberg K, et al. Health of adults aged 22 to 35 years conceived by assisted reproductive technology. Fertility and Sterility. 2019;112(1):130-9
2 Novakovic B, Lewis S, Halliday J, Kennedy J, et al. Assisted reproductive technologies are associated with limited epigenetic variation at birth that largely resolves in adulthood. Nature Communications