A syringe is placed in a three-way stopcock and used to suction if the blood does not flow naturally. This is a preferred method because of the reduced risk of contamination. When the placenta is delivered, another 20-40 mL or more can be collected from the lake at the root of the cord by gentle reverse milking of the cord and multiple aspirations of the engorged vessels on the fetal surface. Cord blood can also be collected after the separation of the placenta. The placenta is suspended from a specially-designed stand with the cord and fetal material hanging down.
Gravity drains the blood into a container.
The final container is labeled properly and taken to the lab for processing. The blood is tested for several infectious diseases, including HIV and hepatitis. And if not already done through amniocentesis or chorionic villus sampling, the blood is HLA-typed. The blood is cryopreserved at - 90 degrees Celsius, then stored in liquid nitrogen until needed. Whether an adult can be successfully and sufficiently transplanted using umbilical cord blood remains to be seen.