(1) This study aimed to evaluate characteristics, perinatal outcomes, and placental pathology of pregnant women with or without SARS-CoV-2 infection in the context of maternal PCR cycle threshold (C_T) values. (2) This was a retrospective case-control study in a third-level health center in Mexico City with universal screening by RT-qPCR. The association of COVID-19 manifestations, preeclampsia, and preterm birth with maternal variables and C_T values were assessed by logistic regression models and decision trees. (3) Accordingly, 828 and 298 women had a negative and positive test, respectively. Of those positive, only 2.6% of them presented mild to moderate symptoms. Clinical characteristics between both groups of women were similar. No associations between C_T values were found for maternal features, such as pre-gestational BMI, age, and symptomatology. A significantly higher percentage of placental fibrinoid was seen with women with low C_Ts (<25; p < 0.01). Regarding perinatal outcomes, preeclampsia was found to be significantly associated with symptomatology but not with risk factors or C_T values (p < 0.01, aOR = 14.72). Moreover, 88.9% of women diagnosed with COVID-19 at <35 gestational weeks and symptomatic developed preeclampsia. (4) The data support strong guidance for pregnancies with SARS-CoV-2 infection, in particular preeclampsia and placental pathology, which need further investigation.

中文翻译：

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妊娠期 COVID-19 感染：PCR 周期阈值、胎盘病理学和围产期结局

(1) 本研究旨在在母体 PCR 周期阈值 (C _T ) 值的背景下评估感染或未感染 SARS-CoV-2 的孕妇的特征、围产期结局和胎盘病理。(2) 这是在墨西哥城一家三级卫生中心进行的回顾性病例对照研究，通过 RT-qPCR 进行普遍筛查。通过逻辑回归模型和决策树评估COVID-19 表现、先兆子痫和早产与母亲变量和 C _T值的关联。(3) 因此，分别有 828 和 298 名女性的测试呈阴性和阳性。在那些阳性者中，只有 2.6% 的人表现出轻度至中度症状。两组女性的临床特征相似。C _T之间没有关联发现了母体特征的值，例如孕前 BMI、年龄和症状。在 C _T较低的女性中，胎盘纤维蛋白的百分比显着更高（<25；p < 0.01）。关于围产期结局，发现先兆子痫与症状显着相关，但与危险因素或 C _T值无关（p < 0.01，aOR = 14.72）。此外，88.9% 在小于 35 孕周被诊断为 COVID-19 且有症状的女性发展为先兆子痫。(4) 数据支持对 SARS-CoV-2 感染妊娠的强有力指导，特别是先兆子痫和胎盘病理学，需要进一步研究。