Characteristics and Maternal and Birth Outcomes of Hospitalized Pregnant Women With Laboratory-confirmed COVID-19

COVID-NET, 13 States, March 1-August 22, 2020

Miranda J. Delahoy, PhD; Michael Whitaker, MPH; Alissa O'Halloran, MSPH; Shua J. Chai, MD; Pam Daily Kirley, MPH; Nisha Alden, MPH; Breanna Kawasaki, MPH; James Meek, MPH; Kimberly Yousey-Hindes, MPH; Evan J. Anderson, MD; Kyle P. Openo, DrPH; Maya L. Monroe, MPH; Patricia A. Ryan, MS; Kimberly Fox, MPH; Sue Kim, MPH; Ruth Lynfield, MD; Samantha Siebman, MPH; Sarah Shrum Davis, MPH; Daniel M. Sosin, MD; Grant Barney, MPH; Alison Muse, MPH; Nancy M. Bennett, MD; Christina B. Felsen, MPH; Laurie M. Billing, MPH; Jessica Shiltz, MPH; Melissa Sutton, MD; Nicole West, MPH; William Schaffner, MD; H. Keipp Talbot, MD; Andrea George, MPH; Melanie Spencer, MPH; Sascha Ellington, PhD; Romeo R. Galang, MD; Suzanne M. Gilboa, PhD; Van T. Tong, MPH; Alexandra Piasecki, MPH; Lynnette Brammer, MPH; Alicia M. Fry, MD; Aron J. Hall, DVM; Jonathan M. Wortham, MD; Lindsay Kim, MD; Shikha Garg, MD


Morbidity and Mortality Weekly Report. 2020;69(38):1347-1354. 

In This Article

Abstract and Introduction


Pregnant women might be at increased risk for severe coronavirus disease 2019 (COVID-19).[1,2] The COVID-19-Associated Hospitalization Surveillance Network (COVID-NET)[3] collects data on hospitalized pregnant women with laboratory-confirmed SARS-CoV-2, the virus that causes COVID-19; to date, such data have been limited. During March 1–August 22, 2020, approximately one in four hospitalized women aged 15–49 years with COVID-19 was pregnant. Among 598 hospitalized pregnant women with COVID-19, 54.5% were asymptomatic at admission. Among 272 pregnant women with COVID-19 who were symptomatic at hospital admission, 16.2% were admitted to an intensive care unit (ICU), and 8.5% required invasive mechanical ventilation. During COVID-19–associated hospitalizations, 448 of 458 (97.8%) completed pregnancies resulted in a live birth and 10 (2.2%) resulted in a pregnancy loss. Testing policies based on the presence of symptoms might miss COVID-19 infections during pregnancy. Surveillance of pregnant women with COVID-19, including those with asymptomatic infections, is important to understand the short- and long-term consequences of COVID-19 for mothers and newborns. Identifying COVID-19 in women during birth hospitalizations is important to guide preventive measures to protect pregnant women, parents, newborns, other patients, and hospital personnel. Pregnant women and health care providers should be made aware of the potential risks for severe COVID-19 illness, adverse pregnancy outcomes, and ways to prevent infection.

COVID-NET conducts population-based surveillance for laboratory-confirmed COVID-19–associated hospitalizations in 14 states encompassing 99 counties*.[3] Thirteen states (California, Colorado, Connecticut, Georgia, Maryland, Michigan, Minnesota, New Mexico, New York, Ohio, Oregon, Tennessee, and Utah) contributed data to this report. Residents of the predefined surveillance catchment area who had a positive molecular test for SARS-CoV-2 during hospitalization or up to 14 days before hospital admission were classified as having a COVID-19–associated hospitalization and were included in COVID-NET surveillance. Persons included in COVID-NET surveillance are referred to as having COVID-19 throughout this report. SARS-CoV-2 testing was performed at the discretion of health care providers or through facility policies dictating uniform or criteria-based testing of patients upon admission. Trained surveillance officers performed medical chart abstractions for a convenience sample of hospitalizations using a standardized case report form. This analysis included women aged 15–49 years who were pregnant at hospital admission. Descriptive statistics were calculated for hospitalized pregnant women with complete chart review and discharge disposition (i.e., discharged or died during hospitalization). Women with one or more signs or symptoms included on the COVID-NET case report form[3] at the time of hospital admission were classified as symptomatic. Birth outcomes were described for pregnancies completed during a COVID-19–associated hospitalization. Reason for hospital admission was collected starting in June. Data were analyzed using SAS software (version 9.4; SAS Institute). This activity was reviewed by CDC and was conducted consistent with applicable federal law and CDC policy. Sites obtained approval for COVID-NET surveillance from their state and local institutional review boards, as required.

During March 1–August 22, 2020, COVID-NET identified 7,895 hospitalized women aged 15–49 years with COVID-19; discharge disposition was determined, and chart review was completed for 2,318 (29.4%) (Figure 1). Among 2,255 (97.3%) women with information about pregnancy status, 598 (26.5%) were pregnant, with median age 29 years. Among 577 (96.5%) pregnant women with reported race and ethnicity, 42.5% were Hispanic or Latino (Hispanic), and 26.5% were non-Hispanic Black (Black) (Table).

Figure 1.

Pregnancy status, signs and symptoms,* and birth outcomes†,§,¶ among hospitalized women aged 15–49 years with COVID-19** — COVID-NET, 13 states,†† March 1–August 22, 2020
Abbreviations: COVID-19 = coronavirus disease 2019; COVID-NET = COVID-19-Associated Hospitalization Surveillance Network.
*Symptomatic women were those who had one or more signs or symptoms (fever/chills, cough, shortness of breath, muscle aches, nausea/vomiting, headache, sore throat, abdominal pain, chest pain, nasal congestion/rhinorrhea, decreased smell, decreased taste, diarrhea, upper respiratory illness/influenza-like illness, wheezing, hemoptysis/bloody sputum, conjunctivitis, rash, altered mental state, and seizure) at hospital admission; asymptomatic women did not have any of these signs or symptoms at admission.
The 448 pregnancies resulting in live births resulted in the birth of 457 newborns; nine women had twins. Two newborns included in this category who were born alive subsequently died during the birth hospitalization.
§Ten completed pregnancies resulted in pregnancy losses. Pregnancy losses might include spontaneous abortion/miscarriage, therapeutic abortion, or stillbirth.
Pregnancies with known preterm status were those resulting in a live birth for which the gestational age at delivery was known. For three pregnancies resulting in live births, the gestational age at the time of birth was unknown.
**Women residing in the predefined COVID-NET surveillance catchment with a positive real-time reverse transcription–polymerase chain reaction (RT-PCR) test for SARS-CoV-2, during hospitalization or up to 14 days before admission. Among the 597 (99.8%) pregnant women for whom the COVID-19 test type was known, all had a positive RT-PCR test result; the COVID-19 test type for one pregnant woman with a positive COVID-19 test result was unknown.
††California, Colorado, Connecticut, Georgia, Maryland, Michigan, Minnesota, New Mexico, New York, Ohio, Oregon, Tennessee, and Utah.

Among 596 women with COVID-19 whose pregnancy trimester was known, 14 (2.3%), 61 (10.2%), and 521 (87.4%) were hospitalized during the first, second, and third trimesters, respectively. The reason for hospital admission was reported for 324 women: 242 (74.7%) were hospitalized for obstetric indications (including labor and delivery), 61 (18.8%) for COVID-19–related illness, and 21 (6.5%) for other reasons. The most common reason for admission during the first or second pregnancy trimester was COVID-19–related illness (56.8%) and during the third trimester, obstetric indications (81.9%). Among hospitalized pregnant women with COVID-19, 20.6% had at least one underlying medical condition; asthma (8.2%) and hypertension (4.3%) were the most prevalent.

Overall, 272 (45.5%) pregnant women with COVID-19 were symptomatic at the time of hospital admission, and 326 (54.5%) were asymptomatic. Women hospitalized during the first or second trimester were more frequently symptomatic (84.0%) than were those hospitalized during the third trimester (39.9%). Among symptomatic women, the most commonly reported symptoms were fever or chills (59.6%) and cough (59.2%) (Figure 2).

Figure 2.

Signs and symptoms* at hospital admission among symptomatic hospitalized pregnant women with COVID-19, by pregnancy trimester — COVID-NET, 13 states,§ March 1–August 22, 2020
Abbreviations: COVID-19 = coronavirus disease 2019; COVID-NET = COVID-19-Associated Hospitalization Surveillance Network.
*Other signs and symptoms reported on the case report form were upper-respiratory illness/influenza-like illness (11 persons), wheezing (six), hemoptysis/bloody sputum (one), conjunctivitis (one), rash (one), altered mental state (one) and seizure (none). The symptoms decreased smell and decreased taste might not have been ascertained for cases admitted before April 1, 2020, when these symptoms were added as options on the case report form.
A total of 272 pregnant women with COVID-19 with at least one sign or symptom at the time of hospitalization were identified in COVID-NET. One hospitalized pregnant woman who was symptomatic at admission was not included in this figure because of missing pregnancy trimester.
§California, Colorado, Connecticut, Georgia, Maryland, Michigan, Minnesota, New Mexico, New York, Ohio, Oregon, Tennessee, and Utah.

Among 272 hospitalized symptomatic pregnant women, 44 (16.2%) were admitted to an ICU and 23 (8.5%) required invasive mechanical ventilation. Two (0.7%) deaths were reported among symptomatic women. No asymptomatic women were admitted to an ICU, required invasive mechanical ventilation, or died.

At hospital discharge, 458 women (76.6%) with COVID-19 had completed pregnancies, including 448 (97.8%) that resulted in live births and 10 (2.2%) in pregnancy losses (Figure 1). Pregnancy losses occurred among both symptomatic and asymptomatic hospitalized women with COVID-19 (Table). Four pregnancy losses (0.9% of completed pregnancies) occurred at <20 weeks' gestation, five (1.1%) at ≥20 weeks' gestation, and one (0.2%) at unknown gestational age. Among 445 pregnancies resulting in live births with known gestational age at delivery, 87.4% were term births (≥37 weeks' gestation), and 12.6% were preterm (<37 weeks). Among pregnancies resulting in live births, preterm delivery was reported for 23.1% of symptomatic women and 8.0% of asymptomatic women. Two live-born newborns died during the birth hospitalization (Table); both were born to symptomatic women who required invasive mechanical ventilation.

*Counties in COVID-NET surveillance: California (Alameda, Contra Costa, and San Francisco); Colorado (Adams, Arapahoe, Denver, Douglas, and Jefferson); Connecticut (Middlesex and New Haven); Georgia (Clayton, Cobb, DeKalb, Douglas, Fulton, Gwinnett, Newton, and Rockdale); Iowa (one county); Maryland (Allegany, Anne Arundel, Baltimore, Baltimore City, Calvert, Caroline, Carroll, Cecil, Charles, Dorchester, Frederick, Garrett, Harford, Howard, Kent, Montgomery, Prince George's, Queen Anne's, St. Mary's, Somerset, Talbot, Washington, Wicomico, and Worcester); Michigan (Clinton, Eaton, Genesee, Ingham, and Washtenaw); Minnesota (Anoka, Carver, Dakota, Hennepin, Ramsey, Scott, and Washington); New Mexico (Bernalillo, Chaves, Doña Ann, Grant, Luna, San Juan, and Santa Fe); New York (Albany, Columbia, Genesee, Greene, Livingston, Monroe, Montgomery, Ontario, Orleans, Rensselaer, Saratoga, Schenectady, Schoharie, Wayne, and Yates); Ohio (Delaware, Fairfield, Franklin, Hocking, Licking, Madison, Morrow, Perry, Pickaway, and Union); Oregon (Clackamas, Multnomah, and Washington); Tennessee (Cheatham, Davidson, Dickson, Robertson, Rutherford, Sumner, Williamson, and Wilson); and Utah (Salt Lake).
45 C.F.R. part 46.102(l)(2), 21 C.F.R. part 56; 42 U.S.C. Sect. 241(d); 5 U.S.C. Sect. 552a; 44 U.S.C. Sect. 3501 et seq.