Two years into the coronavirus disease 2019 (COVID-19) pandemic, we have now seen three main variant waves. We performed a retrospective cohort study of all pregnant patients with COVID-19 at our institution from March 22, 2020, to February 26, 2022, to evaluate disease severity and perinatal outcomes among the variants. Patients were categorized as pre-Delta (March 22, 2020–May 31, 2021), Delta (July 1, 2021–December 15, 2021), or Omicron (December 16, 2021– February 26, 2022) based on variant tracking from the Centers for Disease Control and Prevention and genotype sequencing at our institution. There were fewer cases of severe–critical disease (1.8% Omicron vs 13.3% pre-Delta and 24.1% Delta) and adverse perinatal outcomes during the Omicron wave compared with the pre-Delta and Delta waves.

2019 年冠状病毒病 (COVID-19) 大流行已过去两年，我们现在已经看到了三波主要的变异浪潮。我们对 2020 年 3 月 22 日至 2022 年 2 月 26 日在我们机构的所有感染 COVID-19 的孕妇进行了回顾性队列研究，以评估各变异体的疾病严重程度和围产期结局。根据变异追踪，患者被分为 Delta 前（2020 年 3 月 22 日至 2021 年 5 月 31 日）、Delta（2021 年 7 月 1 日至 2021 年 12 月 15 日）或 Omicron（2021 年 12 月 16 日至 2022 年 2 月 26 日）我们机构的疾病控制和预防中心以及基因型测序。与 Delta 前和 Delta 波相比，Omicron 波期间严重危重症病例（1.8% Omicron vs 13.3% 前 Delta 和 24.1% Delta）和不良围产期结局较少。