One of the most pressing decisions for IVF patients to make is how many embryos to use during a transfer. This a complex subject and as a result we see patient behavior differ depending upon where they live, their age, level of insurance and more. For instance, in the U.S., we do far more multiple-embryo transfer than other developed nations.
The reality is the decision often comes down to two factors: the medical risks of transferring multiple embryos and the speed and cost savings it might confer. From our own survey data, it’s clear U.S. patients receive differing information on what those risks and benefits really are. Here is a more complete picture of the reality, as we see it.
The risks of transferring multiple embryos are well-characterized. This leads to a higher rate of multiple gestation births, which both raises the medical risk to mother and child, and ultimately threatens to impair behavior and cognition for the offspring. One in three sets of twins ultimately will be born sufficiently unwell to be discharged to the NICU.
The benefit multiple embryo-transfer offers, in many cases, is a higher live birth rate on the first transfer, though as we detail, there are plenty of exceptions, especially in younger patients, patients with more embryos available and those who are using PGS-tested embryos.
The reality is that when we compare success rates for patients who use multiple embryos at once, or each of their embryos one at a time, the cumulative success rates look comparable, atleast for younger patients. But yes, to get comprable success rates the single-embryo patients need to do more transfers.
This is a complex decision and requires in-depth education, yet a non-insignificant percentage of patients, about a quarter, felt their discussion with their doctor was incomplete. A fifth were only educated immediately pre-transfer, which is far from ideal. You may need to invite this discussion with your doctor and press him or her on the facts.
Patients are liable to be given differing facts by their clinician. Patients who are younger or living in a state with insurance are more likely to hear cautionary facts about multiple-embryo transfer. Older patients and those living in non-insurance states are more likely to hear the encouraging facts of multiple-embryo transfer.
Ultimately, fertility patients should be prepared for their doctor to have a recommendation (91% of cases) and historically that recommendation has carried the day. As you can see below, when doctors recommend a single-embryo transfer, 75% of patients go along. When they recommend a multiple embryo transfer, 82% go along.
Ultimately, in 2017 the ASRM decided to impose far more stringent guidelines on which type of patient should receive how many embryos. If your doctor is recommending more than this, they should have a superb reason.
There are a host of reasons in the U.S. we have a historical bias for multiple-embryo transfer. First, multiple-embryo transfer drives higher success rates on that first transfer, which bolsters clinic success rates. We seldom look at success rates in the context of embryo-transfer and so it is hard to tell if clinics are actually more skilled, or just prepared to take greater chances with the health of the mother and infant.
A fair amount is made of the economic benefit multiple-embryo transfer offers. In many cases, it helps lower the risk of a second transfer. Yet, in states where IVF is virtually always paid for by insurance (e.g. Illinois, Massachusetts or New Jersey), multiple-embryo transfer rates are still the norm, not the exception: even amongst younger patients, who are particularly well-suited to single embryo transfer.
Finally, as patient decision-makers, we are often divorced from the sizeable downstream financial costs of a multiple birth, which can result in a long, expensive NICU stay. Alternatively, in other countries the government both pays for IVF and for all future medical costs: they deeply care about the financial risks of a multiple-birth pregnancy and use their authority to stamp out multiple-embryo transfers. Whereas today in the U.S., multiple embryo transfer is alive and well, though certainly on the decline.
What can be easily lost on patients is how difficulty the transfer itself can be and how wide the range of expertise is within a clinic and so we strongly encourage patients to push their clinic for success rates by transferring doctor and to ensure that doctor plans to follow the recommended guidelines.