Children conceived using frozen embryos may be at a higher risk of developing childhood cancer

·         A recent study found that children conceived with frozen embryos may be nearly two-and-a-half times more likely to develop cancer than other children.

·         The researchers surveyed 1,085,172 children born in Denmark. 

·         The use of frozen embryos to conceive children has increased in the last few decades because more people are opting to use Invitrofertilization and other fertility preservation methods. 

·         The long-term effects of treatments like IVF have largely remained unstudied. 

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It's been 40 years since the first baby conceived using in vitro fertilization (IVF) was born. Since then, the landscape of fertility preservation options has transformed. 

These kinds of treatments, including IVF and IUI, have become more accessible over the years, making it easier for people to have children later in life.  But the long term effects of treatments that include egg freezing remain largely unstudied, leaving questions as to what their use means for childhood development. 

A group of Danish researchers found that children conceived using frozen embryos are nearly two-and-a-half times more likely to develop childhood cancer than other children.

The study, published in the Journal of the American Medical Association, looked at 1,085,172 children born in Denmark between 1996 and 2012.  For every 100,000 children conceived using frozen embryos, 44.4 developed childhood cancer. But for every 100,000 children born through embryos that weren't frozen — whether through IVF or typical conception — only 17.5 developed childhood cancer. 

Those born using fertility methods that did not involve frozen embryos, like IVF (using fresh embryos) or hormonal treatments, were not at an increased risk.

*Childhood cancer is so rare that the risk is still low

While the increase in the likelihood of developing childhood cancer is statistically significant, it is still a small increase in risk overall because childhood cancer is so rare. 

The study authors noted that one of the greatest limitations of the study was that childhood cancer cases are rare, so it's difficult to draw concrete conclusions about all children born using frozen embryos from the findings. 

Previous research on the long-term effects of fertility treatments on children has linked it to cancer before

The new study isn't the first time researchers have made the connection between cancer and fertility treatments. A smaller Danish study of 690 people drew a similar connection between cancer and fertility treatments. 

The study found that children conceived using certain types of fertility treatment — namely those involving embryo freezing — were at a slightly higher risk of developing children cancer than those birthed without those treatments.
However, like the most recent study, the likelihood of developing childhood cancer was still extremely low, regardless of how a child was conceived.