Background: Delayed cord clamping in full-term neonates is widely recommended, while in practice, it is rarely implemented in cesarean section due to the fear of neonatal jaundice and excessive maternal blood loss. The optimal timing of cord clamping remains uncertain. This study was to fully evaluate the effects of delayed cord clamping on short-term hematological status and jaundice in term neonates delivered by cesarean section.
Methods: This retrospective study enrolled 796 women, who were allocated into the early cord clamping group (n = 377) and the delayed cord clamping group (n = 419). The latter group was further divided into two subgroups (30-60 s, 61-120 s). The outcomes were neonatal transcutaneous bilirubin levels on 0 to 5 days of life and the rate of phototherapy. For neonates who had blood tests on the first three days of life, their hemoglobin and hematocrit were compared among groups.
Results: Compared with the early cord clamping group, delayed cord clamping merely increased the transcutaneous bilirubin level of neonates on the day of birth rather than that on the following five days. The heel peripheral blood sample size of 1-3 days in the early cord clamping group was 61, 25 and 33, and in the delayed cord clamping group was 53, 46 and 32, respectively. Delayed cord clamping at 30-60 s resulted in the higher neonatal hemoglobin level on day 3 and an increased rate of neonatal polycythemia, without a higher rate of phototherapy. Delayed cord clamping beyond 60 s did not further improve hematological status in term neonates born by cesarean section.
Conclusion: In cesarean section, delayed cord clamping for 30-60 s improved the early hematological status of term neonates without the enhanced requirement of phototherapy for neonatal jaundice.
Keywords: Anemia; Cesarean section; Delayed cord clamping; Neonatal jaundice; Phototherapy.