Association between COVID-19 Infection and Miscarriages, What We Really Know?

Background: COVID-19 is a modern worldwide pandemic that affected and continues to affect millions of people around the world. Since the discovery that angiotensin-converting enzyme 2 (ACE2) is the binding site for COVID-19 to achieve cell entry, there has been a continuous debate about the effect of COVID-19 infection in first and second trimester abortions. The aim of this review is to investigate the impact of COVID-19 infection on the incidence of miscarriage. Furthermore, we seek to identify potential pathophysiological mechanisms of early pregnancy loss present in infected women.

Methods: A literature review was conducted on different databases, including PubMed, Google Scholar, Ovid, Science Direct, Scopus, and Cochrane library, between 1 January 2020 and 31 August 2023. A total of 364 articles were identified and 32 articles were ultimately included in the review.

Results: There are several case studies that provide evidence that early pregnancy loss is associated with COVID-19 infection. These findings are not further confirmed by the majority of systematic reviews and meta-analyses, which demonstrate that the total number of miscarriages do not differ significantly between infected and non-infected groups. Furthermore, there are also case reports that associate COVID-19 infection with late second trimester abortions.

Conclusions: Given that the virus persists globally, it is important to gain a better understanding of its associated risks in the reproductive process, and larger, more homogeneous, and controlled studies are required to obtain more robust data that can be meta-analyzed to obtain an overview of this potential relationship.