Among the pregnant women admitted to our hospital in late pregnancy, 1 case was mild type, 16 cases were ordinary type, and 1 case was severe type. The clinical manifestations included fever, cough, sputum, fatigue, chest tightness, shortness of breath, and diarrhea. According to epidemiological statistics, 6 cases had a history of contact with patients of COVID-19, 2 cases of hospital visits, and the remaining 10 patients was not clear about the source of the infection. The peripheral blood leukocytes levels of these pregnant women could be normal, but for a subset of patients they were elevated during bacterial infection. Decrease in lymphocyte counts was also observed in certain patients. ALT, AST, and LDH were increased in some patients. However, serum creatinine, urea, and creatine kinase were within normal range in all the patients. Chest CT of patients with COVID-19 had certain characteristics, and early manifestations were multiple flaky ground-glass shadows . Most patients in this study had typical CT manifestations similar to the general population: multiple flaky, patchy, segmental ground glass shadows in one or both lungs, mainly distributed outside the band. Two patients had pleural effusion in addition to typical CT findings. One patient had occasional cough and denied a history of exposure to COVID-19. Her blood routine showed that white blood cells were in normal range, but lymphocyte count decreased. There was no abnormal radiographic change in CT examination, but the nucleic acid test of SARS-CoV-2 was positive. Therefore, in areas with a high incidence of epidemic cases, patients highly suspected of COVID-19 with no characteristic changes in CT imaging should require further testing with throat swabs. A normal CT result cannot be used as an exclusion criterion for COVID-19.
In this study, 18 patients terminated pregnancy during the 3rd trimester, and the gestational age was from 35+ 5 to 41 weeks. 13 cases were terminated by cesarean section because of labor onset, premature rupture of membranes, severe preeclampsia, scar uterus, and fetal distress. 3 cases of pneumonia did not improve significantly after antiviral therapy, and thus cesarean section performed. 1 case requested for caesarean section at 39+ 5 weeks due to social and psychosocial factors. In addition, 1 case was vaginal delivery. Under strict isolation and active treatment, all the patients had been cured and discharged. Before the outbreak of SARS-CoV-2 pneumonia, the cesarean section rate in the hospital was 48–52%. The indications for cesarean section were scarred uterus, placenta previa, dystocia, multiple pregnancy, preeclampsia, fetal distress, etc. We considered that the indications for cesarean section of pregnancy with COVID-19 should still be based on obstetric management principles. For the patients of mild or ordinary pneumonia, the gestational age could be prolonged properly under monitoring of changes in pneumonia and fetal. If the mother’s condition did not improve and the gestational age of the newborn was assessed to have a certain survival rate, early delivery was beneficial to improve COVID-19 maternal lung ventilation. For patients who are expected to deliver in a short time, we should make preparations for delivery immediately. When closely monitoring mother, fetus and the progress of labor, midwifery personnel should make III-level protective measures to avoid infection to the greatest extent.
SARS-CoV-2 was a novel coronavirus that is pathogenic to humans. Roujian Lu et al. found that SARS-CoV-2 had a similar structure of receptor binding domain as SARS-CoV-1, which indicated that SARS-CoV-2 infection might have a similar pathogenesis as SARS-CoV-1 infection [10, 11]. Some scholars speculated that the risk of vertical transmission of SARS-CoV-2 might be as low as SARS-CoV-1 . The clinical data of 9 pregnant women were analyzed by Zhongnan Hospital of Wuhan University. The nucleic acid tests for SARS-CoV-2 were negative in the amniotic fluid, umbilical cord blood, neonatal pharynx, and breast milk of 6 patients. They believed that the vertical transmission of the SARS-CoV-2 was relatively low . Also, some researchers performed pathological analysis of placenta in 3 pregnant women infected with SARS-CoV-2 in late pregnancy. Histopathological analysis of the placenta revealed 1 case with chorionic hemangioma and another with massive placental infarction. In all 3 cases, various degrees of fibrin deposition inside and around the villi with local syncytia nodules increased. Both placental tissue and neonatal throat swabs tested for SARS-CoV-2 were negative. They concluded that there was no pathological evidence of intrauterine vertical transmission of SARS-CoV-2 . A study of various types of cells at the maternal-fetal interface found that the angiotensin-converting enzyme 2(ACE2), which was the receptor of SARS-CoV-2, expressed at low levels. Furthermore, it suggested that the maternal-fetal interface might not have a potential subgroup of susceptible cells of SARS-CoV-2, and SARS-CoV-2 infection during pregnancy did not cause intrauterine infection through vertical transmission of the placenta . The results of our study was consistent with previous reports, and no vertical transmission of the SARS-CoV-2 was found. However, our study had certain limitations. We only performed swab nucleic acid testing in 18 neonates. No nucleic acid tests were performed on breast milk, placenta, amniotic fluid, and cord blood of pregnant women. Therefore, it is very important to collect evidence for the vertical transmission in the later stage. Additionally, it would be more valuable to evaluate the risk of the vertical transmission based on the data of multiple hospitals.
The outcomes of 18 neonates were as follows: 3 cases of premature infants, 1 case of mild neonatal asphyxia, 5 cases of bacterial pneumonia, 1 case of neonatal gastrointestinal bleeding, 1 case of necrotizing enteritis, 2 cases of hyperbilirubinemia, 1 case of neonatal diarrhea. Among the mothers of 5 newborns with bacterial pneumonia, 4 mothers tested positive for nucleic acid of SARS-CoV-2. The chest radiographs of these 5 neonates showed pneumonia lesion absorption after antibiotic treatment, and they had been cured. The occurrence of perinatal neonatal pneumonia was related to premature rupture of membranes, maternal infection and premature birth . Our study found that the incidence of neonatal bacterial pneumonia was significantly higher than other neonatal diseases when the mother infected with COVID-19 was in the state of inflammatory stress or fever.
Twelve pregnant women were infected with SARS in 2003, and 3 of them died of respiratory failure or infection. Spontaneous abortion occurred in 4 of the 7 early pregnancy patients. In the second or third trimester of pregnancy, 3 of the 5 patients gave birth at 26–32 weeks, and 2 gave birth at 33 weeks and term [17, 18]. Sarah H  summarized the cases of pregnant women with MERS-CoV in the MEDLINE database from 2012 to 2016, of which 2 cases were reported by her. Of all 11 patients, 6 patients were admitted to the ICU, 3 patients died during hospitalization, and the infant mortality rate was 27%. The mortality rate of 11 pregnant women infected with MERS-CoV was not statistically different from the 35% total mortality rate. Compared with previous reports of SARS and MERS, our research included a higher number of pregnancy women with COVID-19, but the maternal and infant outcomes were relatively better. The clinical classification of patients were mostly ordinary type, and the possibility of progress to severe or critical novel coronavirus pneumonia had been reduced after early isolation and drug treatments. However, we should still be vigilant and pay more attention to the monitoring and treatment of pregnant women infected with SARS-CoV-2 pneumonia, and control the disease towards severe infection, ARDS and multiple organ failure which endanger the lives of both the mothers and fetus.