Scientists find that babies born from frozen embryos are at a greater risk of cancer
Children born through the use of frozen embryos may be at higher risk of cancer than children born using other methods, a major Nordic study suggests.
It is estimated that almost one in 12 children in Europe is born after fertility treatments, including in vitro fertilization (IVF).
This type of reproductive technology (ART) allows embryos to be created from a human egg and sperm in a laboratory and, three days later, transferred to the patient's uterus.
But increasingly, IVF embryos are frozen for 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 analyzed medical records from nearly 8 million children in Denmark, Finland, Norway and Sweden.
Of these, more than 170,000 were born after using ART, including 22,630 born after frozen-thawed embryo transfer.
The research found that children born after frozen embryo transfer had an approximately 1.6 to 1.7 times higher risk of cancer than children born after fresh embryo transfer and those born without the help of any fertility treatment.