Influence of SARS-CoV-2 during pregnancy: a placental view.

Since the beginning of the current coronavirus outbreak (COVID-19), there has been great concern over a disease that has spread rapidly in several countries worldwide, with the result of several deaths, including deaths of pregnant women. Therefore, the aim of this study was to conduct a literature review on placental changes in infected pregnant women and/or asymptomatic carriers of COVID-19 during pregnancy, aiming at the possible vertical transmission. A systematic collection was carried out on the effects of that COVID-19 can cause directly and/or indirectly to pregnancy and the placenta in the following databases: Pubmed, Science Direct, Scielo, Lilacs, and Web of Science. For search, the following descriptors were used: placenta, pregnant woman, COVID-19, maternal-fetal. The results indicate transplacental transmission in some cases reviewed in many reports from this study. The presence of the virus was seen in the amniotic fluid, umbilical cord, and peripheral blood. Finally, pathological studies suggest that there are morphological changes related to infection in the placentas. We can conclude that, based on the researched material, there is little evidence of transplacental vertical viral transmission and its respective morphological changes related to viral infection in the placenta.

SARS-CoV, MERS-CoV and SARS-CoV-2 infections in pregnancy and fetal development.

Recently, in China, in 2019, a new type of disease has arisen caused by a new strain of coronavirus, the SARS-CoV-2 virus, considered extremely worrying due to its high infectivity power and the easy ability to spread geographically. For patients in general, the clinical features resulting from respiratory syndromes can trigger an asymptomatic condition. However, 25 % of patients infected by SARS-CoV-2 can progress to severity. Pregnant women are an unknown field in this complex process, and although they have symptoms similar to non-pregnant women, some points should be considered, such as complications during pregnancy and postpartum. Thus, the aim of this study was to understand the consequences of pregnancy and fetal development, caused by infections by the SARS-CoV, MERS-CoV and SARS-CoV-2 viruses. Among the aforementioned infections, MERS-CoV seems to be the most dangerous for newborns, inducing high blood pressure, pre-eclampsia, pneumonia, acute renal failure, and multiple organ failure in mother. This also causes a higher occurrence of emergency cesarean deliveries and premature births, in addition, some deaths of mothers and fetuses were recorded. Meanwhile, SARS-CoV and SARS-CoV-2 appear to have less severe symptoms. Furthermore, although a study found the ACE2 receptor, used by SARS-CoV-2, widely distributed in specific cell types of the maternal-fetal interface, there is no evidence of vertical transmission for any of the coronaviruses. Thus, the limited reported obstetric cases alert to the need for advanced life support for pregnant women infected with coronaviruses and to the need for further investigation for application in clinical practice.