Devroe Johanna, Peeraer Karen, Verbeke Geert, Spiessens Carl, Vriens Joris, Dancet Eline
Leuven University Fertility Centre, University Hospital Leuven, Leuven, Belgium
Development and Regeneration, Laboratory of Endometrium, Endometriosis & Reproductive Medicine, Leuven, Belgium.
BMJ Open. 2020 Oct 8;10(10):e037289. doi: 10.1136/bmjopen-2020-037289.
To study the performance of the 'van Loendersloot' prognostic model for our clinic's in vitro fertilisation (IVF) in its original version, the refitted version and in an adapted version replacing previous by current cycle IVF laboratory variables.
This retrospective cohort study in our academic tertiary fertility clinic analysed 1281 IVF cycles of 591 couples, who completed at least one 2nd-6th IVF cycle with own fresh gametes after a previous IVF cycle with the same partner in our clinic between 2010 and 2018. The outcome of interest was the chance on a live birth after one complete IVF cycle (including all fresh and frozen embryo transfers from the same episode of ovarian stimulation). Model performance was expressed in terms of discrimination (c-statistics) and calibration (calibration model, comparison of prognosis to observed ratios of five disjoint groups formed by the quintiles of the IVF prognoses and a calibration plot).
A total of 344 live births were obtained (26.9%). External validation of the original van Loendersloot model showed a poor c-statistic of 0.64 (95% CI: 0.61 to 0.68) and an underestimation of IVF success. The refitted and the adapted models showed c-statistics of respectively 0.68 (95% CI: 0.65 to 0.71) and 0.74 (95% CI: 0.70 to 0.77). Similar c-statistics were found with cross-validation. Both models showed a good calibration model; refitted model: intercept=0.00 (95% CI: -0.23 to 0.23) and slope=1.00 (95% CI: 0.79 to 1.21); adapted model: intercept=0.00 (95% CI: -0.18 to 0.18) and slope=1.00 (95% CI: 0.83 to 1.17). Prognoses and observed success rates of the disjoint groups matched well for the refitted model and even better for the adapted model.
External validation of the original van Loendersloot model indicated that model updating was recommended. The good performance of the refitted and adapted models allows informing couples about their IVF prognosis prior to an IVF cycle and at the time of embryo transfer. Whether this has an impact on couple's expected success rates, distress and IVF discontinuation can now be studied.
研究“范·伦德洛特”预后模型在其原始版本、重新拟合版本以及用当前周期体外受精（IVF）实验室变量取代先前周期变量的改编版本中，对本诊所IVF的表现。
这项在我们学术性三级生育诊所进行的回顾性队列研究，分析了591对夫妇的1281个IVF周期，这些夫妇在2010年至2018年期间，在我们诊所与同一伴侣完成了至少一个使用自身新鲜配子的第2 - 6次IVF周期，且之前有过一次IVF周期。感兴趣的结果是一个完整IVF周期（包括同一卵巢刺激周期的所有新鲜和冷冻胚胎移植）后活产的几率。模型表现通过区分度（c统计量）和校准（校准模型、IVF预后五分位数形成的五个不相交组的预后与观察到的比率比较以及校准图）来表示。
共获得344例活产（26.9%）。原始范·伦德洛特模型的外部验证显示c统计量较差，为0.64（95%CI：0.61至0.68），且对IVF成功率估计不足。重新拟合模型和改编模型的c统计量分别为0.68（95%CI：0.65至0.71）和0.74（95%CI：0.70至0.77）。交叉验证得到了相似的c统计量。两个模型均显示出良好的校准模型；重新拟合模型：截距 = 0.00（95%CI： - 0.23至0.23），斜率 = 1.00（95%CI：0.79至1.21）；改编模型：截距 = 0.00（95%CI： - 0.18至0.18），斜率 = 1.00（95%CI：0.83至1.17）。对于重新拟合模型，不相交组的预后与观察到的成功率匹配良好，对于改编模型则更好。
原始范·伦德洛特模型的外部验证表明建议对模型进行更新。重新拟合模型和改编模型的良好表现使得能够在IVF周期前和胚胎移植时告知夫妇他们的IVF预后。现在可以研究这是否会对夫妇的预期成功率、痛苦程度和IVF终止产生影响。
