BACKGROUND Perinatal mortality remains high in low- and middle-income countries. Accurate assessment of fetal gestational age is crucial to distinguish between prematurity and intrauterine growth restriction, 2 conditions commonly associated with perinatal mortality that require different preventive strategies and management. Ultrasound measurements of the cerebellum have been shown to be accurate in assessing gestational age during pregnancy, but their postmortem performance has not yet been evaluated. OBJECTIVE We aimed to explore the feasibility and validity of gestational age estimation in fetal and perinatal deaths by ultrasound measurements of the cerebellum. STUDY DESIGN This is an observational cross-sectional study. Between August 2020 and November 2022 postmortem cerebellar ultrasound measurements were conducted in a tertiary referral hospital in Barcelona, Spain. Extrauterine assessment included transcerebellar diameter, cerebellar vermis height, and cerebellar vermis length. Moreover, intrauterine ultrasound and autopsy direct cerebellar assessments were undertaken in a subset of cases. A total of 137 fetal and perinatal deaths [63 (46.0%) fetal deaths, 69 (50.4%) stillbirths, and 5 (3.6%) neonates] were included. First, we correlated different types of transcerebellar diameter measurements between them (intrauterine, extrauterine, and autopsy-based). Then, we evaluated the relationship between the extrauterine cerebellar ultrasound measurements and gestational age, and their performance across trimesters of gestation and in different central nervous system abnormalities. RESULTS Gestational age ranged from 15.2 to 40.6 weeks. High correlation was observed between extrauterine, intrauterine, and autopsy transcerebellar measurements (P<.001) and between all extrauterine cerebellar measurements and gestational age (P<.001). Extrauterine transcerebellar diameter was identified as the strongest predictor of gestational age (coefficient of determination=0.88; P<.001), and its accuracy was not affected by the trimester of gestation, intrauterine growth restriction, or central nervous system alterations. CONCLUSION This study shows the feasibility and accuracy of postmortem gestational age evaluation by extrauterine ultrasound measurements of the cerebellum, especially of transcerebellar diameter. Implementation of this method as part of postmortem assessment could improve cause of death attribution, especially in resource-constrained settings.

中文翻译：

---

通过超声小脑测量评估胎儿和围产期死亡的胎龄。


背景 低收入和中等收入国家的围产期死亡率仍然很高。准确评估胎龄对于区分早产儿和宫内生长受限至关重要，这两种疾病通常与围产期死亡率有关，需要不同的预防策略和管理。小脑的超声测量已被证明在评估怀孕期间的胎龄方面是准确的，但尚未评估其死后性能。目的 我们旨在通过小脑超声测量探讨胎龄估计在胎儿和围生儿死亡中的可行性和有效性。研究设计 这是一项观察性横断面研究。2020 年 8 月至 2022 年 11 月期间，在西班牙巴塞罗那的一家三级转诊医院进行了死后小脑超声测量。宫外评估包括经小脑直径、小脑蚓部高度和小脑蚓部长度。此外，对一部分病例进行了宫内超声和尸检直接小脑评估。共纳入 137 例胎儿和围生儿死亡 [63 例 （46.0%） 胎儿死亡，69 例 （50.4%） 死产和 5 例 （3.6%） 新生儿]。首先，我们将它们之间不同类型的经脑直径测量（基于宫内、宫外和尸检）相关联。然后，我们评估了宫外小脑超声测量与胎龄之间的关系，以及它们在妊娠期和不同中枢神经系统异常中的表现。结果 胎龄为 15.2 至 40.6 周。观察到宫外、宫内和尸检经脑测量之间高度相关 （P<.001） 以及所有宫外小脑测量值与胎龄之间 （P<.001）。宫外经小脑直径被确定为胎龄的最强预测因子 （决定系数 = 0.88;P<.001），其准确性不受妊娠期、宫内生长受限或中枢神经系统改变的影响。结论 本研究通过宫外超声测量小脑，特别是经小脑直径，揭示了死后胎龄评估的可行性和准确性。将这种方法作为尸检评估的一部分实施可以改善死因归因，尤其是在资源受限的环境中。