Department of Clinical Sciences and Community Health, Università degli Studi di Milano, Via. Festa del Perdono, 7 20122 Milano, Milan, Italy; Obstetric and Gynecology Department, Fondazione Ca' Granda, Ospedale Maggiore Policlinico, Via M Fanti, 6, Milan 20122, Italy.
Division of Genetics and Cell Biology, Reproductive Sciences Laboratory, IRCCS Ospedale San Raffaele, Milan, Italy.
Reprod Biomed Online. 2018 Jan;36(1):32-38. doi: 10.1016/j.rbmo.2017.09.012. Epub 2017 Oct 12.
The most common definition of repeated implantation failure (RIF) is the failure to obtain a clinical pregnancy after three completed IVF cycles. This definition, however, may lead to misuse of the diagnosis. To disentangle this, we set up a mathematical model based on the following main assumptions: rate of success of IVF constant and set at 30%; and RIF postulated to be a dichotomous condition (yes or no) with a prevalence of 10%. On this basis, the expected cumulative chance of pregnancy after three and six cycles was 59% and 79%, respectively. Consequently, the false-positive rate of a diagnosis of RIF is 75% and 51%, respectively. Increasing the rate of success of IVF or the prevalence of RIF lowers but does not make unremarkable the rate of false-positive diagnoses. Overall, this model shows that the commonly used definition of RIF based on three failed attempts in a standard population with good prognosis leads to over-diagnosis and, potentially, to over-treatments.
最常见的反复着床失败（RIF）定义是在三个完整的体外受精（IVF）周期后未能获得临床妊娠。然而，这一定义可能导致诊断的滥用。为了理清这一点，我们基于以下主要假设建立了一个数学模型：IVF 的成功率恒定，设定为 30%；并且假设 RIF 是一种二分状态（是或否），患病率为 10%。在此基础上，三个和六个周期后的妊娠累积预期机会分别为 59%和 79%。因此，RIF 诊断的假阳性率分别为 75%和 51%。提高 IVF 的成功率或 RIF 的患病率会降低但不会消除假阳性诊断的发生率。总体而言，该模型表明，基于预后良好的标准人群中三次失败尝试的常用 RIF 定义导致过度诊断，并可能导致过度治疗。
