Newborn babies donít need to be held down around their motherís vagina while the last of the placental blood makes its way through the umbilical cord, according to a new study.
Waiting a couple of minutes after a baby is born to clamp and cut the umbilical cord is generally considered a good idea, and some authorities have recommended holding the newborn level with the vagina so gravity can help draw extra blood from the placenta.
But babies held that way didnít seem to get any more placental blood than babies held in their motherís arms instead, the new study found.
ďThe fantasy that gravity plays a role was based on very old studies,Ē Dr. Nestor E. Vain told Reuters Health.
Vain worked on the study at the Foundation for Maternal and Child Health in Buenos Aires, Argentina.
The uterus continues to contract after the baby is born, and those contractions are what push blood through the umbilical cord, not gravity, he said.
Between 2011 and 2012, Vain and his team recruited about 400 women in labor at three hospitals in Argentina. With hospital cooperation, half of their babies were held at the level of the vagina after birth and the other half were placed on their motherís abdomen or chest for two minutes before the umbilical cord was clamped.
The babies were weighed immediately after birth and again after the cords were clamped.
Based on their weights, babies in both groups seemed to gain about the same amount of blood regardless of where they were held, according to results published in The Lancet. In the abdomen/chest group, babies gained an average of 53 grams, or about a tenth of a pound, compared to 56 grams in the vagina-level group.
ďAt any time during pregnancy in the last trimester, one third of the fetal blood in the baby is circulating in the placenta, which is where the babyís blood goes to get oxygen and sugar from the maternal blood and eliminate carbon dioxide like the kidney of an adult,Ē Vain said.
That blood needs to get to the baby before the cord is clamped or cut, he said. Waiting one to four minutes to clamp decreases the babyís risk of iron-deficiency anemia and neurodevelopmental problems, which are a concern in Western as well as developing countries, he said.
ďIn preterm infants, we know that more blood improves babyís blood pressure, reduces the need for blood transfusions, reduces the risk for having