Maternal mortality in pregnant women with COVID-19 during the early pandemic period (2019–2022): a systematic review of published cases

Pregnant women were at higher risk for Coronavirus disease 2019 (COVID-19), and this infection can lead to adverse effects such as maternal mortality, preterm delivery, and miscarriage. However, there has been limited information available about COVID-19 in pregnancy. This study aimed to report maternal mortality in pregnant women with COVID-19 and how COVID-19 is related to their death, clinical features, and laboratory changes. We conducted a systematic search on PubMed/Medline, Web of Science, and Embase to identify studies addressing maternal mortality and COVID-19 in pregnancy during 2019–2022. The following terms were used: [“maternal mortality”] AND [“COVID-19” OR “SARS-CoV-2” OR “2019-nCoV”]. Fourteen relevant research articles were included in our study. The highest maternal mortality rate due to COVID-19 was reported in the third trimester and postpartum, with 133 mothers (133/172). The most common comorbidities included cardiovascular disease (20%), diabetes (18.3%), and obesity (12.5%). Cardiopulmonary complications caused by SARS-CoV-2 were identified as leading cause of maternal death. Based on the results of the current study, it is evident that COVID-19 and its complications played a significant role in maternal mortality in pregnant women during the early pandemic period (2019–2022). Importantly, these findings reflect an era before widespread vaccination and population immunity. Since 2022, the emergence of new variants (e.g., Omicron) and high vaccination coverage have substantially altered COVID-19 severity in pregnancy. Therefore, these results should be interpreted as historical baseline data rather than current risk estimates. Further studies examining maternal outcomes in the post-vaccination era are strongly recommended.