Analyzed variables
Women were differentiated according to the timing of cord clamping
(early or delayed). Early cord clamping (ECC) and DCC were established
when performed < 30 or > 30 seconds after the
delivery, respectively. Primary variables included: the rate of
perinatal transmission of SARS-CoV-2 and development of COVID-19 disease
in neonates at day 14 of the delivery. Perinatal transmission was
defined by a positive PCR in a nasopharyngeal sample from the neonate.
Given the lack of a uniform criterion about neonatal infection, the
diagnosis was made by PCR from a nasopharyngeal sample, following
specific considerations. If the PCR was positive within 12 hours after
delivery, it was repeated. If this second PCR was negative, the first
PCR was then considered as contaminated or a false positive; however, if
positive, the infection was corroborated. Each case was followed-up at
14 days after delivery, by phone. The state of health of each neonate
was confirmed during the writing of this manuscript (June 2020).
Secondary variables included: the need for neonatal resuscitation,
admission at the intensive care unit (ICU), neonatal symptomatology
suggestive of COVID-19, and rates of skin-to-skin contact and early
breastfeeding. Neonatal symptoms were evaluated at day 14 after
delivery, by completing a clinical questionnaire during a phone
interview.