The study, published by the Cochrane Review Library, set out to determine if delayed cord clamping or umbilical cord milking improves the health outcomes for babies born before 37 weeks' gestation. These interventions were compared with early cord clamping.
Babies born before 37 weeks, or preterm, have poorer health outcomes than babies born at term, particularly if they are born before 32 weeks. They can experience problems with the functioning of many of their major organs including their lungs, gut and hearts, and have a greater risk of dying or having long-term problems such as cerebral palsy. After birth, the babies may need blood transfusions and drugs to strengthen their heart contractions (inotropes) and to raise their blood pressure. It is important to try to find ways of improving the health of these tiny babies.
Heike Rabe, Professor of Perinatal Medicine and Honorary Consultant Neonatologist at Brighton and Sussex Medical School (BSMS), who led the study, said: “Early clamping of the umbilical cord has been standard practice over many years. It allows the baby to be transferred quickly to care from a specialist team of doctors either at the side of the room or in another room. Yet, delayed clamping for half to three or more minutes allows continuing blood flow between the mother and her baby, and this may help the baby to adjust to breathing air. Squeezing blood along the umbilical cord towards the baby (milking the cord) can boost the baby's blood volume, and this may improve the baby's health.
“Our study found that delayed, rather than early, cord clamping may reduce the risk of death before discharge for babies born preterm. As there have only been a few studies that follow babies for health outcomes in early childhood to date and there is insufficient evidence for reliable conclusions on providing immediate care for the baby beside the mother with the cord intact, immediate neonatal care with the cord intact requires further study.”
Researchers collected and analysed 40 published studies, which provided data on 4,884 babies and their mothers. These studies had been undertaken across the world, but mostly in high-income countries and the births were in hospitals which practiced early clamping.
The study, titled ‘Effect of timing of umbilical cord clamping and other strategies to influence placental transfusion at preterm birth on maternal and infant outcomes,’ is published open access.