More than half of pregnant women recently admitted to a UK hospital with covid-19 infection were from black or other ethnic minority groups, finds a national surveillance study published by The BMJ today.
Most women had good outcomes, and transmission of covid-19 to infants was uncommon, but the researchers say the high proportion of women from black or minority ethnic groups admitted with infection "needs urgent investigation and explanation."
Published evidence on the rate, transmission, and effect of covid-19 infection in pregnancy remains limited, but evidence from other similar viral illnesses suggest that pregnant women and their babies are at greater risk of severe illness and death.
So a team of researchers, led by Professor Marian Knight from the Nuffield Department of Population Health, University of Oxford, set out to describe the characteristics and outcomes of pregnant women admitted to a UK hospital with covid-19, in order to inform ongoing guidance and management.
Their findings are based on data from the UK Obstetric Surveillance System (UKOSS) for pregnant women admitted to obstetric units in the UK with confirmed covid-19 infection between 1 March and 14 April 2020.
A total of 427 pregnant women were admitted to hospital with covid-19 during the study period. Most were in the late second or third trimester.
More than half (56%) were from black or other ethnic minority groups (25% of women were Asian and 22% were black), 70% were overweight or obese, 40% were aged 35 or over, and a third had pre-existing conditions.
Forty one (10%) of women needed respiratory support in a critical care unit, and five (1%) women died (three as a direct result of complications of covid-19 and two from other causes).
Twelve (5%) babies born to study mothers tested positive for covid-19, six of them within the first 12 hours after birth.
The high proportion of women from black and other minority ethnic groups admitted to hospital with covid-19 remained after excluding major urban centres from the analysis. This is of concern and should be investigated further, say the authors.
The researchers point to some study limitations that may have influenced their results. Nevertheless, they say these data suggest that most women do not have severe illness and that transmission of covid-19 to infants is uncommon. They also support guidance for continued social distancing measures in later pregnancy.
However, the high proportion of women from black or minority ethnic groups admitted with infection needs urgent investigation and explanation, they conclude.
Peer reviewed? Yes
Evidence type: Observational
Subjects: Pregnant women with covid-19 and their babies