Key Findings from SET-NET Data

This analysis found that among infants born to people who had COVID-19 any time during pregnancy, very few tested positive for SARS-CoV-2 (the virus that causes COVID-19) in their first 6 months. However, infant infection and death were more common, and breastmilk feeding was less common, when the pregnant person had COVID-19 within two weeks before delivery. Overall, infections in infants were more common between the ages of 15 days and 6 months, likely due to household or community transmission.

An analysis of more than 35,000 people with COVID-19 during pregnancy in 2020 showed a higher rate of preterm delivery than the baseline rate of preterm delivery in the United States. In addition, there was a higher rate of preterm delivery among people who were infected during the third trimester compared to people who were infected during their first or second trimester. Among 1,732 people with moderate-to-critical illness and data on COVID-19 treatment, 15.2% received a COVID-19 treatment.

Data reported from five states on breastmilk feeding among people who had COVID-19 during pregnancy in 2020 found that 86% of people reported feeding breastmilk to their infants at delivery. However, people who had COVID-19 14 days or less before delivery and who did not room-in with their newborn after delivery were less likely to feed their infants breastmilk during their delivery hospitalization and may benefit from additional lactation support.

Data collected on 6,336 deliveries among people with COVID-19 during pregnancy from January 20-December 31, 2020 in 21 U.S. state, local, or territorial health departments showed that people who became critically ill with COVID-19 during their second or third trimester of pregnancy were four times more likely to have a preterm delivery (before 37 weeks of pregnancy) compared with people who had mild illness at these same points in pregnancy. Indications of critical illness included intensive care unit (ICU) admission, mechanical ventilation, and other complications.

Among 28,771 newborns born to people with SARS-CoV-2 infection during pregnancy, 3,816 (13%) had a positive or negative test result for COVID-19 and 138 (3.6%) had a positive test result. Neonatal SARS-CoV-2 infection was more frequent among neonates born to people diagnosed with COVID-19 close to delivery (within 14 days of delivery) and among infants born preterm.

Of 6,551 people with laboratory-confirmed and symptomatic COVID-19 during pregnancy included in this analysis, 142 (2.2%) had positive reverse transcription polymerase chain reaction (RT-PCR) test results after more than 90 days and up to 416 days after symptom onset. Data came from 21 U.S. jurisdictions and included people with a first positive RT-PCR test result during pregnancy occurring between March – December 2020, with data reported to CDC up to September 2021.

With data on nearly 4,000 infants born to pregnant people with laboratory-confirmed COVID-19, scientists found a higher percentage of preterm infants than seen nationally in 2019, suggesting that people with COVID-19 in pregnancy might be at risk for having a preterm infant.

In an analysis of 7,950 pregnant women with COVID-19, scientists found that pregnant women who were older than 25 years of age, were employed as healthcare workers, and had underlying medical conditions were at increased risk of developing more severe COVID-19 illness compared with pregnant women without these characteristics. Risk for severe COVID-19 illness increased along with the number of underlying conditions a pregnant woman had.

This report looked at data of pregnant people with hepatitis C infection who had a live birth during 2018-2021 from three U.S. jurisdictions (New York state, excluding New York City; Allegheny and Washington counties, Pennsylvania; and Tennessee). Among the 1418 infants, 89% were born to people with reported substance use during pregnancy. Prematurity, small-for-gestational age, and intensive care unit admission were common among this cohort of infants born to people with hepatitis C in pregnancy with high frequency of substance use. Assessments of recent changes to recommendations for hepatitis C virus screening in pregnancy should evaluate the impact on maternal access to care for both hepatitis C virus treatment as well as substance use disorder, which may contribute to adverse birth outcomes.

An analysis of data from four U.S. jurisdictions found that one fifth of people with hepatitis C virus (HCV) infection during pregnancy first tested positive for HCV before they became pregnant, indicating a missed opportunity to provide curative treatment before pregnancy. The majority (81%) reported substance use, and 39% reported polysubstance use. The high frequency of reported substance use during pregnancy among those with hepatitis C infection highlights the need for integration of substance use screening and services into prenatal and other obstetrical care services.

Between May to November 2022, 769 cisgender women had identified cases of mpox. Among the 23 pregnant people identified with mpox, 4 required hospitalizations, 11 received tecovirimat, and all recovered from mpox infection.

Using 4 years of data (2018-2021) from Arizona and Georgia, scientists examined how often people with syphilis during pregnancy used substances (including tobacco, alcohol, cannabis, illicit use of opioids, and other illicit, nonprescription substances), what treatment they received for syphilis, and how often they delivered an infant with congenital syphilis (either a live birth or a stillbirth). Among pregnant people who used substances and delivered an infant with congenital syphilis, more than one third (38%) did not receive prenatal care and more than half (53%) were not treated for syphilis during pregnancy, making it difficult to prevent congenital syphilis. Up to one quarter (26%) were either incarcerated or experienced homelessness during pregnancy.