Catching Covid-19 in early pregnancy could increase risk of miscarriage

Pregnant women who reported being infected with Covid-19 in their first trimester were more likely to have an early miscarriage, finds a new study led by UCL researchers. However, despite the correlation observed in the COVID-19 Contraception and Pregnancy Study (CAP-COVID), researchers say further studies are needed to evaluate any causal association between SARS-CoV-2 infection in early pregnancy and miscarriage risk. The CAP-COVID study, published in Human Reproduction , asked 3,041 women who were less than 13 weeks pregnant to record their current and past pregnancy complications, their medical history and whether anyone in their household had been diagnosed, or had symptoms of Covid-19, between 21^st May and 31^st December, 2020. The results found that the rate of miscarriage amongst women who were presumed to be infected (had received a positive Covid-19 diagnosis) was 14%, compared to 8% in those presumed to be uninfected and 5% in those who were uncertain of whether they had the virus. After adjusting for age, BMI, ethnicity, smoking status, gestational age and the number of previous miscarriages, the risk of early miscarriage appears to be higher (1.7 times more likely) in the 'presumed infected' group. Co-lead author, Honorary Associate Professor Dimitrios Mavrelos who led the project alongside Honorary Senior Lecturer Ephia Yasmin (both UCL EGA Institute for Women's Health & UCLH Reproductive Medicine Unit), said: "As the Covid-19 epidemic reached pandemic status in mid-2020, little was known about the impact of infection on first trimester pregnancy.