Omicron variant of COVID-19 linked to worsening maternal outcomes in pregnant women

According to a published article in The Lancet.

“Because it is very difficult to predict who will develop symptoms and serious complications, with the exception of overweight or obese women, universal vaccination is essential during pregnancy,” the study authors wrote.

A team of investigators from the UK, US, Pakistan, Argentina and other countries recruited 4,618 pregnant women in a prospective observational study to understand maternal and perinatal outcomes of COVID-19 during pregnancy and the effectiveness of the vaccine. against the omicron variant.

The women were recruited from 41 hospitals in 18 countries, the study authors explained. These hospitals, they noted, are part of a “global network of research institutions that provide routine care to several thousand women and newborns every year.” They also acknowledged that these hospitals were not selected to represent the underlying populations, but rather to allow investigators to enroll the maximum number of diagnosed and undiagnosed women in the shortest possible time.

The study authors matched each woman with lab-confirmed COVID-19 with 2 unmatched women without a diagnosis of COVID-19. These women were enrolled from the day after the World Health Organization declared omicron a variant of concern, November 27, 2021 and June 30, 2022. Investigators included single and multiple live births and stillbirths, as well as newborns with birth defects, they said. They were included in follow-up data up to the time of hospital discharge.

One-third of enrolled women (1,545 women) had a COVID-19 diagnosis from 36.7 weeks, while the remaining two-thirds did not have a COVID-19 diagnosis, the authors said. ‘study. Despite similar demographic characteristics, the study authors noted smokers among both groups (8% among participants diagnosed with COVID-19; 6% among otherwise healthy participants), overweight or obese people ( 49% versus 47%), and those with slightly fewer pre-existing morbidities (18% versus 20%).

The study authors determined that women diagnosed with COVID-19 had an increased risk of maternal morbidity and mortality index (MMMI) and severe perinatal morbidity and mortality index (SPMMI) by compared to their counterparts not diagnosed with COVID-19. Additionally, this group had an increased risk of severe neonatal morbidity index (SNMI), but it was lower, the investigators reported.

Looking at the impact of vaccination, the study authors observed that unvaccinated women with a diagnosis of COVID-19 had a greater risk of MMMI. Additionally, severe cases of COVID-19 symptoms in unvaccinated women increased the risk of serious maternal complications, perinatal and referral complications, intensive care unit admission, or death, the authors found. ‘study.

A majority (63%) of participants had at least a single dose of any COVID-19 vaccine, study authors said, while about half (54%) had full or booster doses. of the vaccine. The study authors determined that the efficacy of the vaccine – that is, all vaccines combined – for severe complications of COVID-19 for all women on a complete regimen was 48% and 76 % after a booster dose. Additionally, for women diagnosed with COVID-19, the vaccine effectiveness of all vaccines combined for participants with a full regimen was 74% and reached 91% after a booster dose, the authors said. of the study.

“COVID-19 in pregnancy, within the first 6 months of omicron as a variant of concern, was associated with an increased risk of serious maternal morbidity and mortality, particularly in symptomatic, unvaccinated women,” they wrote. concluded the study authors. “Women who received full or boosted vaccine doses had a reduced risk of severe symptoms, complications and death. Vaccination coverage of pregnant women remains a priority.