LONDON (Reuters) - Fertility clinics should mainly use single embryos for women younger than 37 to reduce a rate of multiple pregnancies that is higher than in many other European countries, experts said on Wednesday.
The recommendation is aimed at helping clinics meet the Human Fertilisation and Embryology Authority’s three-year target to cut multiple pregnancy rates from about 24 percent to 10 percent.
Multiple pregnancies are the biggest risk for women during fertility treatment and significantly increase the likelihood of miscarriage, premature birth and long-term health problems for the child. They can also endanger a mother’s health.
“What we have been exploring is how can we identify those women most at risk of multiple pregnancy,” Tony Rutherford, a researcher at the reproductive medicine unit at The Leeds Teaching Hospitals, said of the proposal.
More than 3.5 million babies have been born worldwide using assisted reproductive technology since July 25, 1978, when two British doctors delivered the world’s first test-tube baby, Louise Brown, by Caesarean.
That number is growing faster because more women are waiting longer to start having children, and cheaper air travel makes it possible for even more couples to seek in-vitro fertilisation or IVF. Most treatments are among women aged between 30 and 39.
The technique involves surgically removing eggs from a woman’s ovaries and combining them with sperm in the lab. Doctors then pick the best embryos — typically one or two — and implant them in the woman’s uterus.
In recent years, some European governments — for example in Belgium and Scandinavia — have mandated single embryo transfers to reduce multiple pregnancies.
The latest annual figures from Britain show 11,262 children were born through IVF treatment, and of those about 4,000 were twins, according to the HFEA.
Experts from the British Fertility Society and the Association of Clinical Embryologists reviewed data from clinics and determined that 87 percent of multiple pregnancies occur during the first cycle of treatment in women younger than 37.
They called for women in the group who produce high quality embryos to only receive a single transfer during their first cycle to reduce multiple pregnancies. The rest of the embryos should be frozen for later use if needed, they added.
“Elective single embryo transfer plus subsequent frozen embryo replacement can be as effective as double embryo transfer in carefully selected patients,” the experts wrote.
Reporting by Michael Kahn; editing by Maggie Fox and Mark Trevelyan