Babies conceived via assisted reproductive technology, such as in vitro fertilization, have a 36% higher risk of developing a major heart defect than children conceived naturally, a new study finds.
Still, heart defects are relatively rare. The study authors found them in 1.15% of naturally conceived babies and 1.84% of babies born after assisted reproduction. The risk rose to 2.47% for IVF babies born as multiples.
The research — one of the largest studies to date — is based on an analysis of more than 7.7 million births in Denmark, Finland, Norway and Sweden.
“Previous research shows that there are increased risks for babies conceived with the help of assisted reproductive technology. These include preterm birth and low birth weight,” said lead study author Ulla-Britt Wennerholm of the University of Gothenburg in Sweden. “We wanted to investigate whether the risk of heart defects was higher for babies born following assisted reproduction.”
Wennerholm’s team compared data on babies conceived naturally versus via IVF; intracytoplasmic sperm injection (ICSI), when a single sperm is injected directly into an egg during IVF; and a frozen embryo.
The researchers then discerned how many babies in each respective group were diagnosed with a serious heart defect in utero or within the first year of life.
Study authors took into account factors such as the age of the mother at delivery and whether she smoked during her pregnancy or had a history of diabetes or heart defects.
Researchers are hopeful their findings, published last week in the European Heart Journal, lead to timely heart defect diagnoses and life-saving intervention.
“Congenital heart defects can be extremely serious, requiring specialist surgery when babies are very young, so knowing which babies are at the greatest risk can help us diagnose heart defects as early as possible and ensure the right care and treatment are given,” Wennerholm said.
According to the American Society for Reproductive Medicine, 2.5% of all US births are a result of successful IVF treatments.
In Denmark, IVF accounts for around 9% of live births, the highest proportion in any country.
Wennerholm notes, “More and more people are conceiving with the help of assisted reproductive technology, so we might expect to see increases in cases of congenital heart defects worldwide.”
Wennerholm and her team believe there may be a link between infertile parents and babies born with heart defect., “The fact that the risk of heart defects is similar regardless of the type of assisted reproduction used may indicate that there is some common factor underlying infertility in parents and congenital heart disease in their babies,” she said.
IVF was developed in the 1970s primarily to assist women with blocked fallopian tubes.
Since its inception, the technology has been used to help people conceive in other situations, such as women suffering frequent miscarriages, male infertility and couples looking to use a surrogate.
In IVF, the most common form of assisted reproductive technology, eggs are collected from a woman and combined with sperm in a lab to create embryos, which are placed into the uterus.
Patients can get their embryos tested for genetic abnormalities before transfer.
Genetically healthy embryos have a success rate of 60% to 65%. These odds diminish when the woman is older or has uterus conditions that make it difficult for an embryo to implant.
Earlier this year, researchers at the University of California, San Diego, revealed a noninvasive method for better predicting the quality of embryos created through IVF.
The cost of one cycle of IVF can range from $10,000 to $25,000 depending on various medications, fees, procedures and consultations needed for success.
Sometimes it takes several rounds for a baby to be born.
