Is pregnancy a risk factor of COVID-19?

Abstract

This review evaluates whether pregnancy is a risk factor for COVID-19 by looking at the expression of immune markers such as immune cells and cytokines in order to have a better understanding on the pathophysiology of the disease, thus reducing maternal deaths. Pregnant women are more at risk of contracting COVID-19 due to their weakened immune system. Studies demonstrate that COVID-19 is an immune condition which is marked by reduced lymphocytes and elevated selected proinflammatory cytokines. Similar immune expression has been demonstrated in pregnancy by several studies. In addition, the placenta has been shown to possess ACE2 receptors on the villous cytotrophoblast and the syncytiotrophoblast and findings suggest that the coronavirus enters the host cells via these ACE2 receptors. The immune response in pregnancy increases the risk of contracting COVID-19. Both normal pregnancy and COVID-19 are marked by decreased lymphocytes, NKG2A inhibitory receptors, and increased ACE2, IL-8, IL-10, and IP-10 it therefore safer to conclude that pregnancy is a risk factor for COVID-19 development. Furthermore, the presence of the ACE2 receptors in the placenta may increase the risk of mother to baby transmission of the virus. Therefore, more studies investigating the link between pregnancy and COVID-19 are needed.

COVID-19 during pregnancy: an overview of maternal characteristics, clinical symptoms, maternal and neonatal outcomes of 10,996 cases described in 15 countries

“…Conversely, we also suggest, that down-regulation of ACE2 receptors induced by SARS-CoV-2 cell entry might have been detrimental in subjects with pre-existing ACE2 deficiency associated with pregnancy. This association might explain the worse perinatal outcomes described in the literature [26,[43][44][45].…”

COVID-19 and Pregnancy Outcome: An Experience in ‘COVID-19 Management Designated’ Tertiary Care Hospital, Rawalpindi, Pakistan

“…24 However, increased expression of ACE2 receptors over the placenta renders not only mothers more susceptible to COVID-19 but may also facilitate vertical transmission. 10,28 Multiple studies give no evidence of vertical transmission. 20,29,30 and in studies with women affected in the 3 rd trimester, all babies born were negative for SARS-COV-2.…”

“…7,8 Being an immunocompromised state, pregnancy is believed to be an important risk factor for COVID-19 infection. 9,10 Both pregnancy and COVID-19 infection share the same immune response characterized by a decrease in lymphocytes and an increase in certain proinflammatory cytokines. 11,12 Furthermore, placental villi have angiotensin-converting enzyme-2 (ACE2) receptors through which coronavirus enters the host cells.…”

“…These receptors can also facilitate the vertical transmission of infection. 10 As infection is a rise in the general population so are the pregnant women too at more risk. Almost 15,735 pregnant women with laboratory-confirmed infection and 37 deaths have been reported in the United States alone.…”

Posicionamento sobre COVID-19 e Gravidez em Mulheres Cardiopatas – Departamento de Cardiologia da Mulher da Sociedade Brasileira de Cardiologia – 2020

“…De acordo com o conhecimento atual, existem evidências de que gravidez é um fator de risco para COVID-19. 10 As limitações da experiência mundial tornam difícil estabelecer o desfecho dessa infecção durante a gravidez. Além disso, as diferenças nas políticas de saúde pública e nas condições culturais e socioeconômicas em nível mundial não possibilitam que se chegue a conclusões sobre o prognóstico de gestantes com SARS-CoV-2.…”