Results
Data from 475 pregnant women with confirmed SARS-CoV-2 infection and their deliveries were initially included in the study; however, 72 were discarded out because of a lack of information about the timing of the cord clamping. Therefore, 403 cases were finally analyzed. ECC was performed on 231 neonates (57.3%), whereas 172 (42.7%) received DCC. No significant differences were found between ECC and DCC groups in maternal age and time between COVID-19 diagnosis and delivery (Table 1). Regarding maternal symptomatology at the time of delivery, 82 (35.5%) and 149 (64.5%) women showed COVID-19 symptoms or were asymptomatic in the ECC group, respectively. In the case of DCC, 30 women (17.4%) showed symptoms, whereas 142 (82.6%) were asymptomatic. The gestational age at delivery with ECC was significantly lower than DCC (37+9 versus 38+8 weeks, P = .001). The number of instrumental and cesarean deliveries were higher with ECC than DCC (13.0% versus 8.1% for instrumental ones, and 45.9% versus 17.4% for cesarean); whereas the number of eutocic deliveries was higher for DCC (74.4% versus 41.1%). The weight at birth was significantly higher with DCC than ECC (3,210.4 versus 3,065.7 grams, P = .037). Although statistically significant, this difference was not clinically relevant.
A total of 5 positive cases (1.7% of total tests performed) were identified with the nasopharyngeal PCR tests, specifically 2 from the ECC (1.7%) and 3 from the DCC group (3.6%; Table 2). No significant differences between groups were found regarding neonatal tests for COVID-19 (P = .390). All positive cases reported within 12 hours after delivery resulted negative in the confirmation test performed between 12 and 48 hours post-delivery. Therefore, no confirmed cases of vertical transmission were detected. A new positive case was found within 12–48 hours of delivery, which was possibly related with horizontal transmission, through contact with a relative without the use of protection measures (and unknown infection). None of the neonates experienced COVID-19 at day 14 after delivery.
The percentage of mothers who made skin-to-skin contact within the first 24 hours after delivery was significantly higher with DCC (84.3% versus 45.9%, P = .001). Breastfeeding in the immediate postpartum period was also significantly higher with DCC than ECC (77.3% versus 50.2%, P = .001).
No significant differences between groups were found regarding arterial pH and Apgar score at 5 minutes in neonates. A higher percentage of admissions to the ICU were reported in the ECC (16.5% versus 8.1%,P = .015).
Considering the temporal distribution, ECC was more prevalent than DCC during the first few days of the pandemic (5.2% versus 2.3% between 1st and 15th March, 25.5% versus 15.1% between 16th and 31st March, and 31.6% versus 20.9% between 1st and 15th April. Time evolution is shown in Table 3.) The main reason for an ECC was due to maternal COVID-19 disease (37.2%)