COVID-19 Vaccines: 1 Safety Surveillance 2 Manual While there is no indication that pregnant women have an increased susceptibility to infection with SARS-CoV-2, there is evidence that pregnancy may increase the risk of severe illness and mortality from COVID-19 disease in comparison with non-pregnant women of reproductive age. As seen with non-pregnant women, a high proportion of pregnant women have asymptomatic SARS-CoV-2 infection and severe disease is associated with recognized medical (e.g., high body-mass index (BMI), diabetes, pre-existing pulmonary or cardiac conditions) and social (e.g., social deprivation, ethnicity) risk factors. Pregnant women with symptomatic COVID-19 appear to have an increased risk of intensive care unit admission, mechanical ventilation and death in comparison with non-pregnant women of reproductive age, although the absolute risks remain low. COVID-19 may increase the risk of preterm birth, compared with pregnant women without COVID-19, although the evidence is inconclusive.