In 2021, we showed an increased risk associated with COVID-19 in pregnancy. Since then, the SARS-CoV-2 virus has undergone genetic mutations. We aimed to examine the effects on maternal and perinatal outcomes of COVID-19 during pregnancy, and evaluate vaccine effectiveness, when omicron (B.1.1.529) was the variant of concern. INTERCOVID-2022 is a large, prospective, observational study, involving 41 hospitals across 18 countries. Each woman with real-time PCR or rapid test, laboratory-confirmed COVID-19 in pregnancy was compared with two unmatched women without a COVID-19 diagnosis who were recruited concomitantly and consecutively in pregnancy or at delivery. Mother and neonate dyads were followed until hospital discharge. Primary outcomes were maternal morbidity and mortality index (MMMI), severe neonatal morbidity index (SNMI), and severe perinatal morbidity and mortality index (SPMMI). Vaccine effectiveness was estimated, adjusted by maternal risk profile. We enrolled 4618 pregnant women from Nov 27, 2021 (the day after WHO declared omicron a variant of concern), to June 30, 2022: 1545 (33%) women had a COVID-19 diagnosis (median gestation 36·7 weeks [IQR 29·0–38·9]) and 3073 (67%) women, with similar demographic characteristics, did not have a COVID-19 diagnosis. Overall, women with a diagnosis had an increased risk for MMMI (relative risk [RR] 1·16 [95% CI 1·03–1·31]) and SPMMI (RR 1·21 [95% CI 1·00–1·46]). Women with a diagnosis, compared with those without a diagnosis, also had increased risks of SNMI (RR 1·23 [95% CI 0·88–1·71]), although the lower bounds of the 95% CI crossed unity. Unvaccinated women with a COVID-19 diagnosis had a greater risk of MMMI (RR 1·36 [95% CI 1·12–1·65]). Severe COVID-19 symptoms in the total sample increased the risk of severe maternal complications (RR 2·51 [95% CI 1·84–3·43]), perinatal complications (RR 1·84 [95% CI 1·02–3·34]), and referral, intensive care unit (ICU) admission, or death (RR 11·83 [95% CI 6·67–20·97]). Severe COVID-19 symptoms in unvaccinated women increased the risk of MMMI (RR 2·88 [95% CI 2·02–4·12]) and referral, ICU admission, or death (RR 20·82 [95% CI 10·44–41·54]). 2886 (63%) of 4618 total participants had at least a single dose of any vaccine, and 2476 (54%) of 4618 had either complete or booster doses. Vaccine effectiveness (all vaccines combined) for severe complications of COVID-19 for all women with a complete regimen was 48% (95% CI 22–65) and 76% (47–89) after a booster dose. For women with a COVID-19 diagnosis, vaccine effectiveness of all vaccines combined for women with a complete regimen was 74% (95% CI 48–87) and 91% (65–98) after a booster dose. COVID-19 in pregnancy, during the first 6 months of omicron as the variant of concern, was associated with increased risk of severe maternal morbidity and mortality, especially among symptomatic and unvaccinated women. Women with complete or boosted vaccine doses had reduced risk for severe symptoms, complications, and death. Vaccination coverage among pregnant women remains a priority. None.

中文翻译：

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omicron 作为关注变体期间的妊娠结局和疫苗有效性，INTERCOVID-2022：一项跨国观察性研究


2021 年，我们发现怀孕期间感染 COVID-19 的风险增加。此后，SARS-CoV-2病毒发生了基因突变。我们的目的是检查怀孕期间 COVID-19 对孕产妇和围产期结局的影响，并评估当 omicron (B.1.1.529) 是受关注变体时疫苗的有效性。 INTERCOVID-2022 是一项大型前瞻性观察性研究，涉及 18 个国家的 41 家医院。将每名在怀孕期间接受实时 PCR 或快速检测、实验室确诊为 COVID-19 的女性与两名在怀孕或分娩时同时和连续招募的未确诊为 COVID-19 且不匹配的女性进行比较。对母亲和新生儿进行随访直至出院。主要结局是孕产妇发病率和死亡率指数（MMMI）、严重新生儿发病率指数（SNMI）和严重围产期发病率和死亡率指数（SPMMI）。估计疫苗有效性，并根据孕产妇风险状况进行调整。我们招募了 4618 名孕妇，从 2021 年 11 月 27 日（世卫组织宣布 omicron 为关注变种的第二天）到 2022 年 6 月 30 日：1545 名 (33%) 女性诊断出 COVID-19（中位妊娠 36·7 周 [IQR]） 29·0–38·9]) 和 3073 名 (67%) 具有相似人口特征的女性没有诊断出 COVID-19。总体而言，确诊的女性患 MMMI（相对风险 [RR] 1·16 [95% CI 1·03–1·31]）和 SPMMI（RR 1·21 [95% CI 1·00–1]）的风险增加·46]）。与未诊断的女性相比，确诊的女性发生 SNMI 的风险也增加（RR 1·23 [95% CI 0·88–1·71]），尽管 95% CI 的下限交叉一致。诊断为 COVID-19 且未接种疫苗的女性患 MMMI 的风险较高（RR 1·36 [95% CI 1·12–1·65]）。 总样本中严重的 COVID-19 症状增加了严重孕产妇并发症 (RR 2·51 [95% CI 1·84–3·43])、围产期并发症 (RR 1·84 [95% CI 1·02–) 的风险。 3·34]），以及转诊、重症监护病房（ICU）入院或死亡（RR 11·83 [95% CI 6·67–20·97]）。未接种疫苗的女性出现严重的 COVID-19 症状会增加 MMMI (RR 2·88 [95% CI 2·02–4·12]) 和转诊、入住 ICU 或死亡 (RR 20·82 [95% CI 10·10]) 的风险44–41·54]）。 4618 名参与者中的 2886 名（63%）至少接种了一剂疫苗，4618 名参与者中的 2476 名（54%）接种了完整剂量或加强剂量。对于所有接受完整治疗方案的女性来说，疫苗对 COVID-19 严重并发症的疫苗有效性（所有疫苗组合）为 48% (95% CI 22-65)，在加强剂量后为 76% (47-89)。对于确诊为 COVID-19 的女性，采用完整治疗方案的所有疫苗联合使用的疫苗有效性为 74% (95% CI 48-87)，在加强剂量后为 91% (65-98)。怀孕期间的 COVID-19，在 omicron 作为受关注变种的前 6 个月内，与严重孕产妇发病和死亡的风险增加相关，特别是在有症状和未接种疫苗的妇女中。接种完整疫苗或加强疫苗剂量的女性出现严重症状、并发症和死亡的风险降低。孕妇的疫苗接种覆盖率仍然是一个优先事项。没有任何。