Clinical characteristics and intrauterine vertical transmission potential of COVID-19 infection in nine pregnant women: a retrospective review of medical records.
Level 4 - case-series / case-control
Retrospective case series of nine patients without a control group.
PubMed 32151335 · doi:10.1016/S0140-6736(20)30360-3
What was done
Medical records, laboratory results, and chest CT scans were retrospectively reviewed for nine pregnant women with RT-PCR-confirmed COVID-19 pneumonia admitted to a single hospital in Wuhan, China, between January 20 and January 31, 2020. Vertical transmission was evaluated by testing amniotic fluid, cord blood, neonatal throat swab samples, and breastmilk (collected after first lactation) for SARS-CoV-2.
What was found
All nine patients delivered via caesarean section in the third trimester. Maternal symptoms included fever (7/9), cough (4/9), myalgia (3/9), sore throat (2/9), and malaise (2/9). Laboratory findings showed lymphopenia (<1.0 × 10⁹ cells/L) in five patients and elevated aminotransferases in three. Fetal distress occurred in two cases. Zero patients developed severe pneumonia or died by February 4, 2020. All nine infants were born alive with 1-minute Apgar scores of 8–9 and 5-minute scores of 9–10, with no neonatal asphyxia. Amniotic fluid, cord blood, neonatal throat swabs, and breastmilk tested negative for SARS-CoV-2 across the six patients from whom samples were collected.
Why it matters
This study provided some of the earliest clinical characterizations of COVID-19 in pregnancy and found no evidence of intrauterine vertical transmission during the third trimester.
Limits
The study is limited by a very small sample size (n = 9, with viral testing of fetal/neonatal samples completed in only 6). It evaluates only third-trimester infections and caesarean deliveries, leaving early- or mid-trimester transmission risks, vaginal birth risks, and long-term neonatal outcomes unmeasured.
Cited by
- supports A study of nine pregnant women with COVID-19 delivering via cesarean section found all amniotic fluid, cord blood, neonatal throat swab, and breast milk samples tested negative for SARS-CoV-2.