London, Europe Brief News – Babies born through the use of frozen embryos may be at higher risk of cancer than children born through other methods, a large Nordic study suggests.
While the absolute number of children who actually had cancer was low, the researchers say their findings should prompt fertility clinics to veer away from a “freeze-all” approach until more is known about how freezing and thawing embryos can affect the health of future generations.
It’s estimated that nearly one in 12 children in Europe are currently born after fertility treatments, including in vitro fertilisation (IVF).
This type of assisted reproductive technology (ART) allows embryos to be created from a human egg and sperm in a laboratory, and, as early as three days later, to be transferred to the patient’s uterus.
But more and more often, IVF embryos are frozen for a few months – or years – before being thawed and implanted for pregnancy.
For their study, published in the open-access journal PLOS Medicine, researchers at the University of Gothenburg in Sweden analysed medical data from nearly 8 million children in Denmark, Finland, Norway, and Sweden.
Of those, more than 170,000 were born after the use of ART, including 22,630 born after frozen-thawed embryo transfer.
