Severe COVID-19 in pregnancy may increase the risk of pre-labour caesarean birth, a very or extreme preterm birth, stillborn birth, and the need for admission to a neonatal unit, finds a new study.

The study, published in the journal Acta Obstetricia et Gynecologica Scandinavica, indicated that certain pregnant women with COVID-19 who are hospitalised stand a higher risk of developing serious disease. "This new analysis shows that certain pregnant women admitted to a hospital with COVID-19 face an elevated risk of severe disease," said senior author Marian Knight, FMedSci, of the University of Oxford.

"However, it shows once again the strong protective effect of vaccination against severe disease and adverse outcomes for both mother and baby," Knight added. For the study, the research team included 4,436 pregnant women hospitalised in the UK with symptomatic COVID-19 from March 1, 2020, to October 31, 2021 (13.9 per cent of whom had severe COVID-19).

In addition to having increased risks of adverse pregnancy-related outcomes, women with severe infection were more likely to be aged around 30 years, being overweight or obese, be of mixed ethnicity, or have gestational diabetes compared with those with mild or moderate infection, the study said.

"This study emphasizes the importance of ensuring that interventions to promote vaccine uptake are particularly focused towards those at highest risk," Knight said.