Single Embryo Transfer Cuts Multiples
IVF Success Rate High in Good Prognosis Patients
The Trickiest Treatment Group
The findings have the most relevance for women between the ages of 35 and 40 -- the age where infertility treatment decisions are often the most complicated, Milki says.
“Younger women can often achieve good pregnancy rates with only one embryo, and the risk of multiple births is low in older women, even when many embryos are transferred,” he says.
The challenge in women between the ages of 35 and 40 is to be aggressive enough with treatment to achieve a pregnancy and cautious enough to avoid multiple births.
“Couples understand the medical risks of having triplets, but they are much more accepting of twin pregnancies,” Milki says. “When they do understand the risks they are often much more accepting of single-embryo transfer.”
Those risks include a sevenfold increase in the chance of premature birth in twin vs. single-child pregnancies, a 1.7-fold increase in long-term handicaps, and a greater chance of giving birth to a child with cerebral palsy, he says.
A recent study found that couples were much less accepting of a pregnancy involving twins when they understood these risks.
Half as many couples considered twins an optimal outcome of infertility treatment after being counseled about the risks.
Reproductive medicine specialist Bradley J. Van Voorhis, MD, who led the study team, tells WebMD that the policy at his clinic is now mandatory single blastocyst transfer for patients who have a high risk of delivering twins.
The policy has had little impact on per-patient pregnancy rates, but multiple births have fallen by almost half.
Van Voorhis directs the IVF program, and he is a professor of obstetrics and gynecology at the University of Iowa Carver College of Medicine.
“Patients are pretty accepting of single blastocyst transfer when they realize they still have a good chance of achieving a pregnancy,” he says.