COVID-19 and pregnancy: are they friends or enemies?

Novel coronavirus disease (COVID-19) is rapidly spreading all over the world. Although in many cases the infection causes very weak symptoms, it can be severe in patient with diverse chronical diseases and immunological compromising patients. Pregnancy is a unique condition in which mother and fetus peacefully collaborate. Diverse endocrine-immune mechanisms, mostly under progesterone control work together to protect the fetus from maternal immunocompetent cell activation driven rejection. The physiological shift to Th2 dominant environment, while favourable for fetus, it makes mothers susceptible to infective pathogens, making pregnancy during COVID-19 pandemic challenging.

Studies involving COVID-19 in pregnancy and those analysing changes of immune system induced by COVID-19 were searched in databases such as PubMed, Scopus, Google Scholar and ScienceDirect. Databases were searched using a keyword COVID-19/coronavirus, that was combined with following terms: immune system, pregnancy, oestrogen, or progesterone. Search included studies published up to 01.07.2020. Almost 1,500 articles were found, but only 18 met criteria.

Most frequent symptoms of COVID-19 in mothers infected in the late pregnancy were fever and cough accompanied with lymphopenia and elevated C-reactive protein. Mothers reported to have severe disease had comorbidities and were obese. Low rate of neonatal complications of maternal Sars-Coc-2 infection without neonatal mortality was observed.

Currently available data didn't show significant relationship between COVID-19 severity and pregnancy and there is no strong evidence that mother's infection can lead to adverse pregnancy outcome, but further studies are needed to determinate the possible effects of COVID-19 gained during earlier pregnancy.