Study links fetal reduction in multifetal pregnancies, better birth outcomes
Published Monday, May 8, 2017 11:11AM EDT
When would-be parents find themselves pregnant with triplets or twins, it can be heart-wrenching to decide whether to reduce the pregnancies to just twins or a singleton, in hopes of having healthier babies.
A new Canadian study may help make that decision easier.
That study found that reducing twin and triplet pregnancies conceived through fertility treatments results in fewer health complications for the baby.
Multifetal pregnancies have long carried risks, such as prematurity, low birth weight, serious illness, and even stillbirth or death. But with many more parents turning to fertility treatments, that has also resulted in many more pregnancies of twins, triplets or more.
Dr. K.S. Joseph, of the University of British Columbia’s department of obstetrics, says that leaves parents having to decide whether to continue the pregnancy as is, or reduce the number of fetuses.
“The choice is between a non-interventional situation where there is a high risk that the pregnancy will lead to serious complications for all three babies versus choosing to terminate one of the three pregnancies, which is a very difficult decision for the parents to make,” he explained to CTV News.
But, according to the new research that Joseph led, when parents who have used fertility treatment reduce their pregnancies, the babies tend to be healthier.
The study, which looked at multifetal pregnancies in British Columbia between 2009 and 2013, found that the rates of preterm birth, very preterm birth, low birth weight and very low birth weight were significantly lower among triplet pregnancies that had been reduced to twins compared to unreduced triplet pregnancies.
Compared with unreduced twin pregnancies, pregnancies reduced to singletons also had lower rates of preterm birth and low birth weight.
“We saw that reduced pregnancies whether from triplets to twins, or twins to singletons, had a longer pregnancy duration and the babies were healthier following the fetal reduction,” Joseph said.
But that was true only of pregnancies that had been the result of fertility treatments. Among all multifetal pregnancies, rates of death and serious illness were not lower among multifetal pregnancies that had been reduced.
The full results appear in the Canadian Medical Association Journal.
Joseph says before his research, there had never been a study in Canada looking at pregnancy outcomes in reduced multifetal pregnancies resulting from fertility treatment.
“This study will inform the physicians and the parents and provide them with the information that will help them make a choice,” he said, adding: “It could comfort some parents in their decision-making.”
He noted that parents having to make the decision about whether to reduce their pregnancies tend to be older and have often gone through extensive treatment so are keen to have at least one healthy baby.
“And when they conceive triplets, there is a risk the pregnancy will end without any baby. So this information is important for women, maybe older women, who may have other complications like hypertension, in making that decision about what they can expect.”
Lynda Haddon, the past president of Multiple Births Canada, says choosing to reduce a multifetal pregnancy can be heart-wrenching for would-be parents, but she believes it happens more than anyone discusses.
“It’s not a dinnertime conversation. You don’t tell family and friends. There can be judgment,” she said. “A lot of people see it as abortion, not a decision made out of love for all of the children. So it’s a very complicated decision.”
Dr. Tom Hannam, of the Hannam Fertility Centre in Toronto, says the good news is that fetal reduction procedures are being done less and less often.
He says many fertility practices like his are now using the latest technology to choose the highest quality embryos and will often implant only one embryo at a time.
“The number of people who do selective reduction is fortunately very low,” he said, adding he’s hopeful that new drug treatments and procedures will reduce the risks of multiple births even further.
“The selective reduction technique, I am happy to say it is effective. I am even happier to say it will be increasingly unnecessary going forward. “
With a report from CTV medical specialist Avis Favaro and producer Elizabeth St. Philip