Omicron caused rise in COVID cases among pregnant women, but fewer hospitalizations: Newsroom
Emily Adhikari, MD
DALLAS – April 25, 2022 – Women who were pregnant during the recent Omicron surge were diagnosed with COVID-19 at a much higher rate than in previous phases of the pandemic, but were less likely to develop disease serious, a study by UT Southwestern and Parkland Health scientists found. The research, reported in JAMAis the first published evidence documenting how the boom in COVID-19 cases late last year and early this year impacted the health of pregnant women.
“Obstetrics has never stopped during the pandemic. The women still have babies and come for their antenatal care,” the study leader said. Emily Adhikari, MD, Assistant Professor and Specialist in Maternal-Fetal Medicine at UTSW and Medical Director of Perinatal Infectious Diseases at Parkland Health. “It’s important to understand how this virus behaves in the population we serve.”
Dr. Adhikari explained that respiratory infections, including COVID-19, are as contagious for pregnant women as they are for the general population. However, their effects can be much more serious due to the physiological changes that occur during pregnancy: while a woman’s lung capacity decreases by approximately 20-30% during pregnancy, oxygen consumption increases considerably as the fetus grows.
Although previous research, including a study at UTSW, has shown hospitalizations of pregnant women increased during the Delta wave of COVID-19, no research has yet quantified the severity of the Omicron variant in this population.
To that end, Dr. Adhikari, along with colleagues in the Women’s and Infants’ Health specialty at Parkland and the Departments of Pathology and Pediatrics at UT Southwestern, collected data from patients who received prenatal care at Parkland. Health, the Dallas County system encompassing a centralized system. acute care hospital and 10 community antenatal clinics. Researchers collected information on positive cases and the severity of their illness, which meant the patient needed supplemental oxygen or higher level support such as a high-flow nasal cannula, ventilation mechanical or extracorporeal membrane oxygenation (a type of life support that temporarily replaces the heart). and pulmonary function) – from May 17, 2020 to January 29, 2022.
Dr Adhikari and his colleagues found that 2,641 positive cases were diagnosed during this period, which covered a pre-Delta phase, the Delta surge and the Omicron surge. Their analysis showed that during the Delta surge, the case rate was three times higher than during the pre-Delta period. The case rate during the Omicron surge was 10 times higher than the pre-Delta period. However, while Delta cases were about three times more severe than pre-Delta cases, Omicron cases were about 80% less severe, Dr Adhikari said.
She noted that although vaccination may have played a role in decreasing disease severity, this variable was taken into account, suggesting that the differences may be due to other factors, such as behavior. of the particular variant of SARS-CoV-2 or immunity against previous diseases. infection. Because the future of the pandemic remains uncertain, Dr. Adhikari added, vaccination will be essential to help pregnant women stay healthy if the next variant causes more severe illness.
“We are very fortunate that although Omicron caused more cases than Delta, it was a less severe variant. If the same proportion of positive patients had ended up on oxygen or ventilators, we would have been overwhelmed,” Dr Adhikari said. “We have no control over what the next variant will be, but pregnant women have control over whether to receive the COVID-19 vaccine, which has been shown to help prevent serious illness and spread.”
Other researchers who contributed to this study include Jeffrey A. SoRelle, Jessica Morse, Jessica Pruszynski, and Catherine Y. Spong, all of UT Southwestern; and Lorre MacDonald of Parkland Health.
Dr. SoRelle is the inventor of PCR genotyping tests for variants and is entitled to income from their use.
About UT Southwestern Medical Center
UT Southwestern, one of the nation’s leading academic medical centers, integrates pioneering biomedical research with exceptional clinical care and education. The institution’s faculty has received six Nobel Prizes and includes 25 members of the National Academy of Sciences, 16 members of the National Academy of Medicine, and 14 researchers from the Howard Hughes Medical Institute. Full-time faculty of more than 2,800 people are responsible for groundbreaking medical advances and committed to rapidly translating scientific research into new clinical treatments. UT Southwestern physicians provide care in more than 80 specialties to more than 117,000 inpatients, more than 360,000 emergency room cases, and oversee nearly 3 million outpatient visits annually.