We investigated the detection rate of clinically significant chromosomal microarray analysis (CMA) results in pregnancies with sonographic diagnosis of fetal corpus callosum anomalies (CCA) or posterior fossa anomalies (PFA).

All CMA tests in pregnancies with CCA or PFA performed between January 2015 and June 2020 were retrospectively evaluated from the Israeli Ministry of Health database. The rate of CMA with clinically significant (pathogenic or likely pathogenic) findings was calculated and compared to a local Israeli cohort of 5,541 pregnancies with normal ultrasound.

One hundred eighty-two pregnancies were enrolled: 102 cases with CCA and 89 with PFA (9 cases had both). Clinically significant CMA results were found in 7/102 of CCA (6.9%) and in 7/89 of PFA (7.9%) cases. The CMA detection rate in pregnancies with isolated CCA (2/57, 3.5%) or PFA (2/50, 4.0%) was lower than in nonisolated cases, including additional CNS and/or extra-CNS sonographic anomalies (CCA-5/45, 11.1%; PFA-5/39, 12.8%), but this was not statistically significant. However, the rate among pregnancies that had extra-CNS anomalies, with or without additional CNS involvement (CCA-5/24, 20.8%; PFA-5/29, 17.2%), was significantly higher compared to all other cases (p = 0.0075 for CCA; p = 0.035 for PFA). Risk of CMA with clinically significant results for all and nonisolated CCA or PFA pregnancies was higher compared to the background risk reported in the control cohort (p < 0.001), but was not significant for isolated cases.

Our findings suggest that CMA testing is beneficial for the genetic workup of pregnancies with CCA or PFA, and is probably most informative when additional extra-CNS anomalies are observed.

我们调查了超声诊断胎儿胼胝体异常 (CCA) 或后颅窝异常 (PFA) 的妊娠中具有临床意义的染色体微阵列分析 (CMA) 结果的检出率。

2015 年 1 月至 2020 年 6 月期间对 CCA 或 PFA 妊娠进行的所有 CMA 测试均根据以色列卫生部数据库进行回顾性评估。计算了具有临床显着性（致病性或可能致病性）结果的 CMA 率，并与以色列当地 5,541 例超声正常妊娠队列进行比较。

共纳入 182 例妊娠：102 例患有 CCA，89 例患有 PFA（9 例两者都有）。在 7/102 例 CCA（6.9%）和 7/89 例 PFA（7.9%）病例中发现了具有临床意义的 CMA 结果。妊娠合并孤立性 CCA (2/57, 3.5%) 或 PFA (2/50, 4.0%) 的 CMA 检出率低于非孤立性病例，包括额外的 CNS 和/或 CNS 外超声检查异常 (CCA-5/ 45，11.1%；PFA-5/39，12.8%），但这没有统计学意义。然而，妊娠中出现中枢神经系统外异常（无论是否有额外中枢神经系统受累）的比率（CCA-5/24，20.8%；PFA-5/29，17.2%）与所有其他病例相比显着较高（p = CCA 为 0.0075；PFA 为p = 0.035)。与对照组报告的背景风险相比，所有和非孤立的 CCA 或 PFA 妊娠具有临床显着结果的 CMA 风险较高 ( p < 0.001)，但对于孤立病例而言并不显着。

我们的研究结果表明，CMA 检测有利于 CCA 或 PFA 妊娠的基因检查，并且在观察到额外的中枢神经系统外异常时可能提供最多的信息。