How is cord blood collected?
It literally only takes minutes to save the stem cells in cord blood. Once the umbilical cord is clamped, it is wiped with antiseptic and a needle is inserted into the vein in the umbilical cord to withdraw a few ounces of blood.
There are three methods of collection in common use. One is to hang a blood bag lower than the mother and let gravity draw blood down the tube into the bag. This method is used in most countries of the world, because it has the fewest steps, and therefore the fewest opportunities for mistakes or contamination.
The second method is to actively draw the blood out, just like when a person has a blood draw for a medical test. The draw can be done with a standard syringe or with a bulb in the tubing of the blood bag that creates suction. Studies have shown that actively drawing the blood will collect a larger volume faster.
Third, some banks collect cord blood "ex utero" which means "outside the uterus". They wait until the placenta is delivered, and then a trained technician takes it into another room and puts it on a high shelf so that all of the blood in the umbilical cord and some from the placenta can be drained.