How many embryos transferred

The implantation rate is the proportion of transferred embryos that implant in the uterine lining. These embryos must then continue to develop until we can detect a fetal heartbeat.

Implantation rate is therefore the ratio of fetal hearts to transferred embryos. In IVF, implantation rates once were highly dependent on the age of the female who provided the eggs, as egg quality declines rapidly with age. The implantation rates can increase by genetically screening the embryos before transfer. Additionally, it can help to transfer the embryos into a uterine environment that has not been subjected to ovarian stimulation, such as with frozen embryos, egg donation cycles or gestational carrier cycles.

The greater the implantation rate, the less need to transfer multiple embryos to achieve pregnancy, creating a lower risk of a multiple pregnancy. Many couples facing infertility love the idea of having twins or even triplets. The birth of healthy twins is an enormous contrast against years of failure to achieve pregnancy or birth.

But twins are not always born healthy. All patients should consider having a single embryo transfer in an attempt to have one healthy baby at a time for both the safety of the mother and child. Multiple gestations can cause health issues for the mother high blood pressure, diabetes, need for a cesarean section and delivery complications as well as complications for the babies preterm delivery, low birth weight, delayed lung development, neurological issues.

As a result, the American Society for Reproductive Medicine ASRM and Society for Assisted Reproductive Technology SART revised their recommendations regarding the number of embryos to transfer in in an effort to promote singleton gestations and reduce the number of multiple pregnancies.

The ASRM recommendations are based on embryo quality, which accounts for several characteristics:. Embryo Developmental Stage: embryos on day 3 of development cleavage stage or embryos on day 5 of development blastocyst stage. Euploid Embryo: an embryo with a normal chromosomal complement based on pre-implantation genetic testing for aneuploidy PGT-A. Favorable Prognosis: a patient with a euploid embryo or one or more high quality embryos based on appearance or a patient with a history of a live birth from an IVF cycle.

The ASRM recommends that all patients, regardless of age, who have a euploid embryo have an eSET because PGT-A has been shown to increase the likelihood of implantation and live birth while reducing the chance of miscarriage. Women with pre-existing conditions that may be dangerous in the setting of a multiple pregnancy should not have more than one embryo transferred at a time.

The amount of information given to patients is woefully inadequate. Clinics want to keep up their numbers. Most patients are not informed of the risks of having twins. The field is moving toward SET. Patients may also want twins, rather than two separate pregnancies, to reduce financial as well as physical and psychological stresses and burdens involved with each cycle. Providers are often acutely aware of the financial pressures on patients. Then, we would have greater ability to do single-embryo transfers.

Patients confront both financial and non-financial burdens:. If I were in her place, I would be more likely to transfer two. Individual patients face not only improved odds of a take-home baby, but lower expenses, which physicians in other areas of medicine, generally covered by insurance, may not normally consider. In trying to estimate the odds of success per embryo for any one patient, providers balance several competing sets of statistics, including their own overall experience and effectiveness with past patients:.

When we transfer two, usually only one takes. So we transfer two. If our rate of twins was higher, we probably would go to SET. Transferring three? Extremely rare. If we had a lot of recipients get pregnant with twins, the doctors would feel more comfortable doing single-embryo transfers. Still, questions arise as to what rate of twins would be high enough to prompt SET.

Importantly, not all providers feel the data are sufficiently compelling regarding the risks involved in multiple births. Quadruplets not grey at all. Twins are really not grey. Concerning a patient who ultimately refused to reduce from three fetuses, this physician added:. Providers may thus weigh their views of the data, especially in the face of strong patient desires to have more than one child. Yet many commentators have strongly disagreed that the evidence is insufficient, given the relatively high rate of complications faced by twins and triplets.

Providers who have seen close-up the physical harm of multiple births may perhaps be more convinced. I have seen first-hand what could happen: I know people who went through IVF, and ended up with extremely premature infants in the NICU, born at 25 weeks. Yet physicians who feel that the data are insufficient may consequently mention or discuss these risks with patients, little, if at all:.

The marginal increased risks may be low for each individual patient, but become of concern from a broader public health perspective; yet providers may only factor these larger social costs when they have themselves witnessed or experienced them. Doctors and patients may also transfer more embryos than needed to avoid later retrospective regret, frustration and anger.

Physicians may agree to additional embryo transfers in order to increase their published success statistics:. Part of the motivation for some physicians is to get their numbers up of take-home babies per cycle. Providers may also seek to satisfy and thereby keep their patients, which can further prompt transfer of two or more embryos. Big money. One physician transfers just single embryos, but feels able to do so only because of a lack of competition — no other clinic exists within hundreds of miles:.

The other nearest IVF centre is three or four hours away from us. The number of clinics in a particular geographic area may thus affect clinic policies. Many physicians want to improve their statistics; and the current data-reporting rules require that providers list pregnancy rates but not implantation rates , further motivating transfer of extra embryos:.

The reporting system disincentivizes transferring fewer embryos. We look mostly at pregnancy rates, rather than implantation rates. If the guidelines say one, a lot of patients want to put back two. Altering reporting requirements can reduce the number of embryos transferred, but significant obstacles can impede such changes:. Implantation rates are very down in the depths of the reporting system. Reporting is in fact optional rather than mandatory for physicians in many other countries, where the doctors do not all list their success rates, perpetuating problems.

You can choose not to. Transferring double embryos skews success rate data, but does not necessarily mean that those clinics are more successful. In various ways, doctors may also manipulate the data they provide. Physicians felt that to get good rates, some colleagues carefully selected or rejected certain patients, or only treated patients with very high-quality embryos:. So she underwent five stimulations — five egg retrievals for a cumulative of 10 eggs retrieved and she had only one embryo transferred.

He tells people what they want to hear. Minimal stimulation is great, but really the risk of IVF is the egg retrieval, not the stimulation. We can do just as good: Look at our rates! People are choosing patients based on the FSH or their ovarian reserve, cherry-picking the best patients to try to have their best results.

Yet gaming the statistics can produce problems — most egregiously with Octomom:. Octomom was a terrible outcome. To try to improve pregnancy rates, the doctors were putting back more and more embryos, and in one case got burned.

Clinics may manipulate reported rates in other ways as well — e. To boost their reported success rates, providers may also select or refuse to treat patients in various ways, and reject certain patients whom other physicians might accept:. Doctors differ somewhat in turning away patients who have a reduced prognosis for pregnancy. We get patients who have been turned away elsewhere for things like elevated FSH. Questions therefore arise, too, of whether to treat patients with low odds of success, and if so when, in what way and how to decide.

The quality of reported data can also vary widely — the completeness, accuracy and validity of diagnoses or outcomes. Consequently, data from Europe may not always be fully comparable:.

The more data you get, the less accurate it is. But a lot of programmes see it as another task to do, and just put in whatever data are the fastest to put in. You end up with numbers, but they may not be accurate, particularly with diagnosis.

How do you diagnose male factor in an IVF cycle? Doctors handle ovulatory factor and endometriosis differently. Or ovarian reserve — half the time people forget that that even exists in the diagnostic codes. So when you start getting too much data, people are not interested in putting the information in; or the numbers are subjective.

You get the numbers, but what do they mean? When patients request additional transfers to increase their odds of success and decrease their out-of-pocket costs, providers may have difficulty weighing the clashing considerations involved. Clinicians vary in whether to yield to these requests, and if so, when:. They have premature delivery and use up resources more rapidly.

Providers vary in how they then proceed — whether effectively to let the patient decide, reflecting in part rising patient consumerism:. Who makes those decisions? Doctors used to make all the calls: this is the way we do it. Patients were accepting.

Lately, it seems that the patient gets whatever she wants. Healthcare costs are increasing hugely because of the attitude: we can do it. We get paid to do it. But no one asks should we do it. These attitudes may also be changing over time. Physicians face questions of whether they should make these decisions on their own or in conjunction with other professionals.

Providers differ, too, in whether they consult with a Quality Assurance QA or other type of committee. A physician in a private practice said:. If anything looks exceptional, we bring it to QA for all of us to discuss.

Our patients sign a consent form about how many embryos to transfer. We treat our patients. We are very proud of American pregnancy rates, but we need to get our twin and triplet rates down. The type of clinic can shape these decision-making processes. Providers who work within academic medical contexts or hospitals can face additional implicit and explicit pressures:.

My hospital had a meeting of the medical executive directors with people, and they had me talk with a maternal-fetal specialist about the impact of IVF on the hospital. I thought it was going to be a lynching. From a cost point of view, you want to have singletons because the complications otherwise are difficult. I have patients who lose twins at 23 weeks. Some complicated twin pregnancies are in bed for six months. I have competitors in my region with pretty terrible records: triplets, quads.

Hospital environments, in which physicians periodically have to present their work to others outside assisted reproductive technology, can thus act as a form of oversight or social control. The fact that relatively high rates of both twin and higher-order multiple births continue poses critical questions concerning the need for possible additional guidelines, or for regulations.

Competing potential risks and benefits of such additional policies need to be weighed against each other. These clinicians opposed rules rather than guidelines , or stricter mandates that would diminish their autonomy — stressing that clinical judgment can play an important role in these decisions. Yet even though providers may not all follow certain guidelines, they tended to oppose more stringent approaches, feeling that current guidelines, rather than tighter regulations, suffice:.

The question becomes: What exactly is a guideline? Should doctors be punished for not adhering? Should there be rules, rather than guidelines? Yet, while preferring suggested guidelines — rather than regulations — this doctor nonetheless queries their scope, meaning and implications. A broad continuum exists of levels and types of guidelines, based on several characteristics e.

Providers may feel that changes to the reporting policies are needed, but will be elusive due to the complex federal bureaucratic structures and processes involved. While changes in reporting requirements may have helped decrease the rates of births of three or more infants at a time, reduction in the frequency of twins may be harder:.

Because that has to be the incentive. They are very interested, but there is that conflict. They have to push it through. Physicians may therefore also be somewhat ambivalent about maximizing individual patient versus broader public health benefits. These clinicians generally favour increasing professional self-regulatory mechanisms first, before initiating government regulations:. SART wants to set up guidelines for very stringent monitoring of clinic performance, and ask clinics with poor performance to change, taking steps from there.

It should start with self-regulation. There have been improvements over time. The threat of government regulation, if models of professional self-regulation fail, could potentially enhance adherence, though it has not yet proven sufficient. To reduce the incidences of twins and other multiple births, other government policies, concerning insurance coverage, may also then be needed:.

I see the result of twins and triplets, and the maternal complications for ovarian stimulation — people hospitalized during an IVF cycle.

But patients and doctors are willing to do it, and try to transfer more, and not be so cautious, because the patient is paying for it. These data, the first to explore several critical aspects of how providers view and make decisions about how many embryos to transfer, highlight how professional recommendations and guidelines in this area can contain flexibility and ambiguities, and lack enforcement, raising challenges, tensions and dilemmas that providers and patients therefore confront.

Though the previous prior literature has focused largely on limitations in insurance coverage as contributing to high rates of twins, the present data suggest how other, non-economic factors — social, psychological, cognitive, medical, logistical and professional — can play critical roles as well.

Though, as found in Denmark, patients may still prefer twins, even in countries that provide insurance, the present data probe how providers and patients then confront and respond to ensuing tensions, given professional recommendations favouring SET.

The present data also suggest possible strategies that have not been previously reported for addressing these problems, and several directions for future research. Specifically, eight findings that have not been presented in the literature have key implications for future research, practice, education and guidelines.

Secondly, while Jungheim et al. These data extend and build substantially on prior findings that the median length of time of consulting about these issues with providers was 5 min Kalra et al. The present data add considerably to the past literature, in suggesting that providers differ considerably in what they actually say, how thoroughly they discuss these issues; whether they communicate the risks involved, and if so which risks, how effectively and when e.

These data suggest that providers may not fully explain or convey these risks, and may even minimize them; and that patients may also then minimize these dangers, or feel that these odds do not apply to them. Thirdly, while recommendations in certain countries e. These data suggest that patients may seek rationalizations for why these risks will not apply to them: for example because they exercise and are healthy.

Patients in other areas of medicine commonly minimize or deny possible risks to themselves Rabinowitz and Peirson, , and do so here, too. Physicians must obtain informed consent, and patients thus need to understand the risks and benefits involved, but the present data suggest that that may not always occur. While Jungheim found that most clinics deviated from guidelines, due to patient requests, the current data suggest that patient requests themselves may vary widely in how informed and firm they are.

Therefore, the present data suggest clinicians should not always simply follow patient requests, but instead should ascertain how fully informed and strong these requests are.

Guidelines should, arguably, also specify that providers should carefully discuss specific relevant details with patients e. Studies in other areas of medicine show that patients may benefit most from being told not either absolute or relative rates alone, but rather both, along with proportions e.

These data also suggest, for the first time, several reasons for these perceptions of the data as insufficient. For any one patient, the odds of success with twins are relatively good i. Rather, paediatricians, not reproductive endocrinology and infertility REI specialists, are responsible for, and have experienced difficulties in, treating harmful outcomes that twins face, for example in the NICU. The risks may thus be easy for REI specialists and prospective patients to discount.

The costs generated by these risks also accrue not to these REI specialists, but to society and the eventual parents.