Women are more likely to die in pregnancy if they catch Covid, according to researchers, who found the infection raised the risk of a swath of serious illnesses for mothers and their newborns.
Reports throughout the pandemic have highlighted how pregnant women are particularly vulnerable to the virus, with doctors urging women to take up the offer of Covid vaccination to reduce the risk to themselves and their children.
But differences in how studies are done and the patients involved have made it hard to reach detailed conclusions about the impact of the disease, particularly in low-income countries, where few studies have been carried out.
The latest research pooled data from more than 13,000 unvaccinated pregnant women reported in a dozen studies in as many countries. By analysing the data, the scientists aimed to reach reliable conclusions about the risks the infection posed to pregnant women around the world.
Dr Emily Smith, an assistant professor of global health at George Washington University in Washington DC, and her colleagues found that, in the studies, typically 3% of pregnant women with Covid were admitted to intensive care, four times the figure for uninfected women. About 2% of those infected needed mechanical ventilation to help them breathe.
The infection was also linked to a greater death rate. In the studies analysed, 7% of pregnant women with Covid died, compared with a fraction of 1% of those who avoided the virus. Nearly a fifth of the Covid-infected pregnant women developed pneumonia, making the diagnosis 23 times more common than in uninfected women.
Further risks affected the newborn babies, according to the study in BMJ Global Health, with unvaccinated Covid-infected mothers more likely to give birth prematurely and have their babies admitted to neonatal intensive care. Pre-term babies have a greater risk of lifelong health issues, and can have delayed cognitive development in early childhood.
“We found that women who have Covid in pregnancy are at greater risk of ending up in the intensive care unit or even dying or having some pregnancy-related problems like pre-eclampsia, as compared to their peers who were pregnant at the same time but didn’t get Covid,” Smith said.
“We also find that [for] mums who had Covid in pregnancy, their babies were more likely to be born too soon, or pre-term, and the babies had an increased risk of ending up in the neonatal intensive care unit.
“The implications here are that it’s really important if you are pregnant, or you’re thinking about becoming pregnant, to get vaccinated. This can really reduce the risk of having some of these bad outcomes for mum or for baby,” she added.
While the findings reflect the impact of Covid on pregnancies over the course of the pandemic, none of the women involved had been vaccinated, and the study did not distinguish between different Covid variants. In the UK, and many other countries, most people have some immunity to Covid through vaccination or previous infection that helps fend off the virus and its worst effects.
Beyond protecting women and babies during pregnancy, recent research shows that Covid vaccination reduces the risk of babies being admitted to hospital with the disease in the first six weeks of life. The protection probably comes from antibodies triggered by the vaccine passing from the mother to the child in the womb.
• The headline and subheading of this article were amended on 17 January 2022 to more accurately reflect the wording of the research findings.
