Pregnancy and infant outcomes by trimester of SARS-CoV-2 infection in pregnancy-SET-NET, 22 jurisdictions, January 25, 2020-December 31, 2020.

OBJECTIVES: We describe clinical characteristics, pregnancy, and infant outcomes in pregnant people with laboratory-confirmed SARS-CoV-2 infection by trimester of infection. STUDY DESIGN: We analyzed data from the Surveillance for Emerging Threats to Mothers and Babies Network and included people with infection in 2020, with known timing of infection and pregnancy outcome. Outcomes are described by trimester of infection. Pregnancy outcomes included live birth and pregnancy loss (<20 weeks and ≥20 weeks gestation). Infant outcomes included preterm birth (<37 weeks gestation), small for gestational age, birth defects, and neonatal intensive care unit admission. Adjusted prevalence ratios (aPR) were calculated for pregnancy and selected infant outcomes by trimester of infection, controlling for demographics. RESULTS: Of 35,200 people included in this analysis, 50.8% of pregnant people had infection in the third trimester, 30.8% in the second, and 18.3% in the first. Third trimester infection was associated with a higher frequency of preterm birth compared to first or second trimester infection combined (17.8% vs. 11.8%; aPR 1.44 95% CI: 1.35-1.54). Prevalence of birth defects was 553.4/10,000 live births, with no difference by trimester of infection. CONCLUSIONS: There were no signals for increased birth defects among infants in this population relative to national baseline estimates, regardless of timing of infection. However, the prevalence of preterm birth in people with SARS-CoV-2 infection in pregnancy in our analysis was higher relative to national baseline data (10.0-10.2%), particularly among people with third trimester infection. Consequences of COVID-19 during pregnancy support recommended COVID-19 prevention strategies, including vaccination.

Six-Month Outcomes of Infants Born to People With SARS-CoV-2 in Pregnancy.

OBJECTIVES: To assess the 6-month incidence of laboratory-confirmed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, postnatal care, hospitalization, and mortality among infants born to people with laboratory-confirmed SARS-CoV-2 infection during pregnancy by timing of maternal infection. METHODS: Using a cohort of liveborn infants from pregnancies with SARS-CoV-2 infections in the year 2020 from 10 United States jurisdictions in the Surveillance for Emerging Threats to Mother and Babies Network, we describe weighted estimates of infant outcomes from birth through 6 months of age from electronic health and laboratory records. RESULTS: Of 6601 exposed infants with laboratory information through 6 months of age, 1.0% (95% confidence interval: 0.8-1.1) tested positive, 19.1% (17.5-20.6) tested negative, and 80.0% (78.4-81.6) were not known to be tested for SARS-CoV-2. Among those ≤14 days of age, SARS-CoV-2 infection occurred only with maternal infection ≤14 days before delivery. Of 3967 infants with medical record abstraction, breastmilk feeding initiation was lower when maternal infection occurred ≤14 days before delivery compared with >14 days (77.6% [72.5-82.6] versus 88.3% [84.7-92.0]). Six-month all-cause hospitalization was 4.1% (2.0-6.2). All-cause mortality was higher among infants born to people with infection ≤14 days (1.0% [0.4-1.6]) than >14 days (0.3% [0.1-0.5]) before delivery. CONCLUSIONS: Results are reassuring, with low incidences of most health outcomes examined. Incidence of infant SARS-CoV-2, breastmilk feeding initiation, and all-cause mortality differed by timing of maternal infection. Strategies to prevent infections and support pregnant people with coronavirus disease 2019 may improve infant outcomes.

SARS-CoV-2 infections among neonates born to pregnant people with SARS-CoV-2 infection: Maternal, pregnancy and birth characteristics.

BACKGROUND: Multiple reports have described neonatal SARS-CoV-2 infection, including likely in utero transmission and early postnatal infection, but published estimates of neonatal infection range by geography and design type. OBJECTIVES: To describe maternal, pregnancy and neonatal characteristics among neonates born to people with SARS-CoV-2 infection during pregnancy by neonatal SARS-CoV-2 testing results. METHODS: Using aggregated data from the Surveillance for Emerging Threats to Mothers and Babies Network (SET-NET) describing infections from 20 January 2020 to 31 December 2020, we identified neonates who were (1) born to people who were SARS-CoV-2 positive by RT-PCR at any time during their pregnancy, and (2) tested for SARS-CoV-2 by RT-PCR during the birth hospitalisation. RESULTS: Among 28,771 neonates born to people with SARS-CoV-2 infection during pregnancy, 3816 (13%) underwent PCR testing and 138 neonates (3.6%) were PCR positive. Ninety-four per cent of neonates testing positive were born to people with infection identified ≤14 days of delivery. Neonatal SARS-CoV-2 infection was more frequent among neonates born preterm (5.7%) compared to term (3.4%). Neonates testing positive were born to both symptomatic and asymptomatic pregnant people. CONCLUSIONS: Jurisdictions reported SARS-CoV-2 RT-PCR results for only 13% of neonates known to be born to people with SARS-CoV-2 infection during pregnancy. These results provide evidence of neonatal infection identified through multi-state systematic surveillance data collection and describe characteristics of neonates with SARS-CoV-2 infection. While perinatal SARS-CoV-2 infection was uncommon among tested neonates born to people with SARS-CoV-2 infection during pregnancy, nearly all cases of tested neonatal infection occurred in pregnant people infected around the time of delivery and was more frequent among neonates born preterm. These findings support the recommendation for neonatal SARS-CoV-2 RT-PCR testing, especially for people with acute infection around the time of delivery.

Recurrent SARS-CoV-2 RNA Detection after COVID-19 Illness Onset during Pregnancy.

The Surveillance for Emerging Threats to Mothers and Babies Network conducts longitudinal surveillance of pregnant persons in the United States with laboratory-confirmed severe acute respiratory syndrome coronavirus 2 infection during pregnancy. Of 6,551 infected pregnant persons in this analysis, 142 (2.2%) had positive RNA tests >90 days and up to 416 days after infection.

Risk Factors for Illness Severity Among Pregnant Women With Confirmed Severe Acute Respiratory Syndrome Coronavirus 2 Infection-Surveillance for Emerging Threats to Mothers and Babies Network, 22 State, Local, and Territorial Health Departments, 29 March 2020-5 March 2021.

BACKGROUND: Pregnant women with coronavirus disease 2019 (COVID-19) are at increased risk for severe illness compared with nonpregnant women. Data to assess risk factors for illness severity among pregnant women with COVID-19 are limited. This study aimed to determine risk factors associated with COVID-19 illness severity among pregnant women with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. METHODS: Pregnant women with SARS-CoV-2 infection confirmed by molecular testing were reported during 29 March 2020-5 March 2021 through the Surveillance for Emerging Threats to Mothers and Babies Network (SET-NET). Criteria for illness severity (asymptomatic, mild, moderate-to-severe, or critical) were adapted from National Institutes of Health and World Health Organization criteria. Crude and adjusted risk ratios for moderate-to-severe or critical COVID-19 illness were calculated for selected demographic and clinical characteristics. RESULTS: Among 7950 pregnant women with SARS-CoV-2 infection, moderate-to-severe or critical COVID-19 illness was associated with age 25 years and older, healthcare occupation, prepregnancy obesity, chronic lung disease, chronic hypertension, and pregestational diabetes mellitus. Risk of moderate-to-severe or critical illness increased with the number of underlying medical or pregnancy-related conditions. CONCLUSIONS: Older age and having underlying medical conditions were associated with increased risk of moderate-to-severe or critical COVID-19 illness among pregnant women. This information might help pregnant women understand their risk for moderate-to-severe or critical COVID-19 illness and can inform targeted public health messaging.