No medical scientist would accept a single case report as an adequate level of evidence to warrant changes in clinical practice. Yet, paradoxically, here is our medical speciality, based on a single case, arguing in support of exactly such policy changes. Therefore, the by now infamous case of the Suleman octuplets raises some rather disturbing questions about scientific integrity and political expediency.
In a series of articles in Fertility and Sterility, the official organ of the American Society for Reproductive Medicine, two prominent reproductive endocrinologists Citation[1,2] and one ethicist Citation[3] recently commented on consequences of the Suleman case on practice of infertility in the USA. Although making many valid points, all three unfortunately reached the fundamentally flawed conclusion that Suleman indeed had relevance to medical practice in the specialty of reproductive endocrinology and infertility. Headlines of their respective papers reflected this: Ory defined the case as “transformative” Citation[1]; Stillman suggested that “this aberration can teach us something” Citation[2]; and Rosenthal, incredibly, suggested that we live in an “age of octuplets” Citation[3].
Had the level of medical care approached generally accepted standards of care in the specialty, Suleman may, indeed, have had relevance. Far removed from even the minimum standards, however, one wonders how a case like this could ever affect practice.
Ory Citation[1] and Stillman Citation[2] correctly point out that knowledge of what exactly transpired in the case is incomplete since the treating physician has not come forward with information (which medical journal would not love to publish this case report?). Ory, however, also notes correctly that simple math demonstrates that the medical care Suleman received was not even close to minimal standards of care.
Current guidelines recommend that not more than two embryos should be transferred into women in their 20s Citation[4,5]. At this age, with an average implantation chance of approximately 30% per embryo, one creates, by implanting two embryos, approximately a 10% chance of twin pregnancy. At 0.9% total twin pregnancies in the general population, some are also the consequence of splitting of single embryos (monozygotic twins) Citation[6].
Octuplets, therefore, can result from implantation of four monozygous twins (requiring the transfer of at least four embryos), implantation of four nonidentical twins (requiring transfer of at least eight embryos) and/or any combination of these two. Excluding extremely rare monozygotic triplets Citation[7–9], octuplets therefore practically cannot be conceived with transfer of less than four embryos, twice what is currently recommended at Suleman’s age Citation[4], and not even considering her historically high success rates with prior IVF attempts.
According to Suleman Citation[1], it is likely that more embryos than that were transferred, and one has to wonder how many more. Indeed, even the transfer of eight embryos still creates a statistically highly improbable scenario for octuplet conception: at 30% implantation chance per embryo, the likelihood for all embryos to implant is similar to winning the lottery (0.38 = 0.000656); the chance of four transferred embryos splitting (at approximately 10% likelihood) and implanting is even lower (∼0.00000672).
Ory notes that Suleman claimed transfer of six frozen–thawed embryos Citation[1]. Since thawed embryos have even lower implantation rates than fresh embryos, Ory calculated the statistical likelihood of eight embryos implanting (six singletons and two monozygotic twins) at 1 in 3.4 trillion – not a very credible scenario!
Medical care in Suleman was, therefore, extremely far outside of currently accepted standards of care. Why such a case should allow for corrective reflections on current standards of care is perplexing. In our opinion, Ory, Stillman and Rosenthal also potentially create medico–legal jeopardy by, at least hypothetically, impugning perfectly reasonable practice patterns as “associated” with the highly inappropriate medical care of Suleman.
By demonstrating how far outside current practice standards Suleman really took place, the case actually reaffirms currently existing practice guidelines, which correctly define such practices as extreme outliers Citation[4,5].
Therefore, why Suleman should in any aspect speak to the issue of single embryo transfer (SET), as suggested by Rosenthal Citation[3] and Stillman Citation[2], is unclear. We, in a number of publications, questioned support for SET Citation[10–14]. Stillman’s strong support of SET recalls the recently frequently heard political aphorism “of letting no crisis pass” without using it to support popular ideas of the moment.
Medicine is, however, different from politics, and should neither use political tactics to support scientific arguments, nor succumb to political pressures in formulating policy. Suleman is a good example. To consider the Suleman octuplets a “transformative” event, as suggested by Ory Citation[1], therefore appears inappropriate. There really is nothing to learn from the case, as suggested by Stillman Citation[2], except, of course, what should not be done under any circumstances. And this single case does not even come close to suggesting that we face an “epidemic of octuplet pregnancies”, as implied by Rosenthal Citation[3].
The Suleman case should simply be viewed as an extremely poorly managed infertility case, which has little, if anything, to say about thousands of infertility cases managed on a daily basis in an entirely proper manner.
Financial & competing interests disclosure
Both authors are coinventors of already granted, and still pending US patents, none of which relates in any way to the issues discussed in this manuscript. Both authors have in the past received research support, travel funds and speakers honoraria from various pharmaceutical and medical device companies, with none of them relating to the topic covered here. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.
No writing assistance was utilized in the production of this manuscript.
References
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