Methods
This was a retrospective cohort study conducted at a single university
affiliated, tertiary medical center. The center treats a heterogeneous
population with over 10,000 deliveries per year. The study cohort
included pregnant women admitted to the obstetrical emergency unit for
delivery during the mask-wearing period during the COVID-19 pandemic
(April 19 to June 27, 2020), starting seven days after initiation of the
mask-wearing regulations in our country, to account for the delay
between erythropoietin secretion and the rise in hemoglobin levels. We
compared these women’s characteristics and outcomes to two pre-pandemic
time frames- the parallel period in 2019 (April 19 to June 27, 2019),
and a longer period between March 21, 2011 and April 18, 2020.
We abstracted labor and delivery charts from the electronic medical
record database of the labor and delivery ward of our center. The
following data were extracted: patient characteristics (age, body mass
index, smoking, COVID-19 infection status and hemoglobin, platelets,
fibrinogen and white blood cells levels); delivery and postpartum
characteristics (gestypothermic treatment.
Maternal body mass index (BMI) was calculated according to height and
weight at admission. Post-partum hemorrhage was defined by The American
College of Obstetricians and Gynecologists as cumulative blood loss of
greater than or equal to 1,000 mL or blood loss accompanied by signs or
symptoms of hypovolemia within 24 hours of the birth process. Composite
bleeding was defined as the presence of post-partum hemorrhage of blood
products transfusion. Composite neonatal outcome included the presence
of any of the neonatal outcomes studied.
Institutional review board approval was obtained for this retrospective
study on March 30,2020 (# 7068-20-SMC).