A surveillance study of more than 6,000 women who gave birth in Canada during the pandemic suggests that those infected with COVID-19 were at higher risk for hospitalization and intensive care unit (ICU) admission than those of nonpregnant women of childbearing age.University of British Columbia researchers led the observational study, which also found that infected pregnant women may have been at significantly increased risk for preterm birth compared with their uninfected peers.Most cases in pregnancy symptomaticThe team studied 6,012 women from six Canadian provinces who tested positive for COVID-19 at any point during their pregnancy (all but 17.1% of them symptomatic) from Mar 1, 2020, to Oct 31, 2021, a period that included Delta variant domination but not the emergence of Omicron.Their outcomes were compared with those of age-matched women infected with COVID-19 and uninfected pregnant women from the same pandemic period.The included provinces were Alberta, British Columbia, Manitoba, Nova Scotia, Ontario, and Quebec.
During the study period, almost all COVID-19 cases (98.7%) occurred among unvaccinated pregnant women. The most common symptoms were cough (48.6%) and fever (24.7%).Of the infected pregnant women, the largest proportion (35.7%) were diagnosed at 28 to 37 weeks' gestation.
Median age was 31 years, and 37.8% of participants were White, followed by South Asian (18.4%), Black (12.1%), other (including Indigenous, 11.8%), and East or Southeast Asian (8.3%).Among infected pregnant women, non-White race was disproportionately represented compared with the general population (62% vs 20%).