Covid and Pregnancy: The risks

Jul 21, 2021

Data collected from pregnancy outcomes with the presence of SARS-CoV and MERS-CoV infections and those related to inflammatory and thrombotic changes in the placenta indicate that placental and neonatal infections can occur and that maternal infection is associated with placental changes.
Maternal inflammation can cause a variety of consequences throughout the child’s life. Therefore, it can be assumed that the proinflammatory state of SARS-CoV-2 infection during pregnancy may lead to adverse consequences in children. In addition to the potential risk of vertical transmission, SARS-CoV-2 may indirectly lead to perinatal and long-term adverse neurodevelopmental outcomes through maternal immune activation (MIA). Therefore, investigations of inflammatory dysregulation in pregnant women with SARS-CoV-2 and longitudinal studies of developmental outcomes in children exposed to SARS-CoV-2 are necessary to ensure adequate care. Most pregnant women are asymptomatic or have mild disease. However, any infection during pregnancy presents potential risks. A recent study found that 3% of pregnant women with SARS-CoV-2 required intensive care, with cases of preterm labor and perinatal death. Viral infections during pregnancy can lead to many placental and neonatal conditions and can cause villitis and miscarriage, as well as being transmitted to the newborn during labor.

SARS-CoV presents as a disease similar to influenza and pneumonia; Possible complications during pregnancy may include maternal death, hypoxia, disseminated intravascular coagulopathy, intrauterine fetal death, intrauterine growth retardation, premature delivery, and miscarriage. In women who were cured of SARS, the placenta during the first trimester appeared normal, whereas the placentas of women with active SARS infection showed increased intervillous and subchorionic fibrin, attributed to maternal hypoxia or increased thrombotic activity. MERS-CoV emerged in June 2012 in the Arabian Peninsula. Similar to SARS-CoV, MERS-CoV infects the lower respiratory tract, causing severe pneumonia. So far, there have been only 11 cases of MERS-CoV infection of pregnant women. Most MERS-CoV infections have resulted in adverse outcomes ranging from preterm labor to maternal and fetal death. The mortality rate of MERS-CoV infection is similar in pregnant women compared with nonpregnant patients. Given the high mortality rate, it is likely that the infection causes placental changes similar to those seen in SARS-CoV infections.
Most reported cases of SARS-CoV-2 positive pregnancies to document negative polymerase chain reaction (PCR) results for SARS-CoV-2 in the newborn, placenta, cord blood, and vaginal secretions. However, there are cases of infants who tested positive for SARS-CoV-2 after delivery, as well as some infants who had positive IgM antibodies to SARS-CoV-2. The SARS-CoV-2 infection causes inflammatory and vascular changes in the placenta, and these could have deleterious effects on both mother and fetus, and we could even go so far as to talk about neurological inflammation before birth.


Appropriate means for neonatal screening have not yet been established, and serologic testing for SARS-CoV-2 is not stable at this time and consequently, it is difficult to interpret these cases. It appears that the majority of infants born to SARS-CoV-2 positive or convalescent mothers have no viremia, congenital infection, or viral replication in the nasopharynx. There are several cases of possible SARS-CoV-2 infection in both the placenta and the newborn but most with the presence of relatively mild symptoms. Certain evidence suggests that maternal inflammation associated with SARS-CoV-2 may confer a long-term risk of neuropsychiatric disorders in children. Maternal Immune Activation (MIA) has been described as a “neurodevelopmental disease principle” that increases the susceptibility of individuals to interacting genetic and environmental risk factors that may trigger neuro- or psychopathologies later in life. The link between MIA and mood disorders, such as depression and bipolar affective disorder in children, has also been suggested. Regarding the complications of SARS-CoV-2 infection in pregnancy, several cases of fetal loss and preterm delivery due to fetal distress have also been reported in SARS-CoV-2-positive pregnant women; some studies have found that the rate of preterm delivery in SARS-CoV-2-infected patients is higher than in the general pregnant population. Preterm infants born to mothers with SARS-CoV-2 should be closely monitored for short- and long-term complications.


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