Physiological, mechanical, and immunologic alterations in pregnancy could potentially affect the susceptibility to and the severity of COVID-19 during pregnancy. Owing to the lack of comparable incidence data and the challenges with disentangling differences in the susceptibility from different exposure risks, the data are insufficient to determine whether pregnancy increases the susceptibility to SARS-CoV-2 infection. The data support pregnancy as a risk factor for severe disease associated with COVID-19; some of the best evidence comes from the United States Centers for Disease Control and Prevention COVID-19 surveillance system, which reported that pregnant persons were more likely to be admitted to an intensive care unit, require invasive ventilation, require extracorporeal membrane oxygenation, and die than nonpregnant women of reproductive age. Although the intrauterine transmission of SARS-CoV-2 has been documented, it appears to be rare. It is possibly related to low levels of SARS-CoV-2 viremia and the decreased coexpression of angiotensin-converting enzyme 2 and transmembrane serine protease 2 needed for SARS-CoV-2 entry into cells in the placenta. Evidence is accumulating that SARS-CoV-2 infection during pregnancy is associated with a number of adverse pregnancy outcomes including preeclampsia, preterm birth, and stillbirth, especially among pregnant persons with severe COVID-19 disease. In addition to the direct impact of COVID-19 on pregnancy outcomes, there is evidence that the pandemic and its effects on healthcare systems have had adverse effects such as increased stillbirths and maternal deaths on the pregnancy outcomes. These trends may represent widening disparities and an alarming reversal of recent improvements in maternal and infant health. All the 3 COVID-19 vaccines currently available in the United States can be administered to pregnant or lactating persons, with no preference for the vaccine type. Although the safety data in pregnancy are rapidly accumulating and no safety signals in pregnancy have been detected, additional information about the birth outcomes, particularly among persons vaccinated earlier in pregnancy, are needed.

怀孕期间的生理、机械和免疫变化可能会影响怀孕期间对 COVID-19 的易感性和严重程度。由于缺乏可比较的发病率数据以及区分不同暴露风险的易感性差异的挑战，数据不足以确定怀孕是否会增加对 SARS-CoV-2 感染的易感性。数据支持怀孕是与 COVID-19 相关的严重疾病的危险因素；一些最好的证据来自美国疾病控制和预防中心的 COVID-19 监测系统，该系统报告称，孕妇更有可能被送进重症监护室、需要有创通气、需要体外膜肺氧合以及死亡高于未怀孕的育龄妇女。尽管 SARS-CoV-2 的宫内传播已有记录，但似乎很少见。这可能与 SARS-CoV-2 病毒血症水平低以及 SARS-CoV-2 进入胎盘细胞所需的血管紧张素转换酶 2 和跨膜丝氨酸蛋白酶 2 的共表达减少有关。越来越多的证据表明，怀孕期间感染 SARS-CoV-2 与许多不良妊娠结局有关，包括先兆子痫、早产和死产，尤其是患有严重 COVID-19 疾病的孕妇。除了 COVID-19 对妊娠结局的直接影响外，有证据表明，这一流行病及其对医疗保健系统的影响还对妊娠结局产生了不利影响，例如死产和孕产妇死亡增加。这些趋势可能代表着差距的扩大以及孕产妇和婴儿健康方面近期改善的令人震惊的逆转。 美国目前提供的所有 3 种 COVID-19 疫苗均可供孕妇或哺乳期人士接种，对疫苗类型没有偏好。尽管怀孕期间的安全性数据正在迅速积累，并且尚未检测到怀孕期间的安全信号，但仍需要有关出生结果的更多信息，特别是在怀孕早期接种疫苗的人中。