Clinical characteristics and intrauterine vertical transmission potential of COVID-19 infection in nine pregnant women: a retrospective review of medical records
Chen H, Guo J, Wang C, et al. Clinical characteristics and intrauterine vertical transmission potential of COVID-19 infection in nine pregnant women: a retrospective review of medical records [published correction appears in Lancet. 2020 Mar 28;395(10229):1038]. Lancet. 2020;395(10226):809‐815. doi:10.1016/S0140-6736(20)30360-3
Review written by:
Natalie Fiszer & Sean Bramley, edited by Elizabeth Harty
Yellow - The study demonstrates important findings on SARS-CoV-2 and pregnancy but its validity and generalizability are limited by small sample size and short onset of infection.
The authors present a retrospective review based on medical records of nine, COVID-19 positive, pregnant women at Zhongnan Hospital of Wuhan University. Each of the nine women presented with a mild case of COVID-19, was in the third trimester of pregnancy, and underwent a caesarean section. Maternal throat swabs were collected to test the mothers for COVID-19. None presented underlying diseases; however, one patient developed gestational hypertension and a second developed preeclampsia at 31 weeks. All patients were given nasal cannula oxygen support and empirical antibiotic treatment; six patients received antiviral therapy. Cesarean delivery was conducted for each patient based on uncertainty of the vaginal delivery risks of vertical transmission. All cases resulted in live birth, with four being preterm but past 36 weeks of gestational age. The nine neonates presented an Apgar score of 8-9 at 1 minute of life and an Apgar score of 9-10 at 5 minutes of life. No neonates required advanced care.
Images of chest CT scans are provided for all nine pregnant women; only one patient did not demonstrate ground-glass opacities. In addition, amniotic fluid, cord blood, neonatal throat swabs, and breast milk samples were collected from six women and their respective neonate; none of the samples were positive for SARS-CoV-2
Each of the nine women underwent a cesarean section, limiting the information gained regarding the risk for intrapartum mother-to-child transmission of SARS-COV-2 during vaginal delivery. Additionally, no samples of shedding in birth canals or vaginal mucosa were collected.
The women included in this study developed COVID-19 in the third trimester, signifying a lack of information for intrauterine infection for patients who test positive for the virus earlier in pregnancy.
The small sample size was further hindered by maternal-fetal biofluid collection being limited to only six of the nine women included in this review.
The patients presented a short time period between onset of illness and delivery. Each of the nine women delivered within seven days of a positive diagnosis of COVID-19.
Conclusions of this review are limited by the fact that each of the nine cases of COVID-19 was mild. None of the women developed pneumonia that required medical ventilation, and none had a high fever (>39°C or 102.2°F).
Variation in care given and labs obtained as well as small sample-size limit any conclusions about COVID-19 pathogenesis differing in pregnant women.