The blood that remains in the placenta after the umbilical cord is clamped is referred to as cord blood. This blood is typically discarded after delivery along with the rest of the placenta unless you specifically request its donation to a blood bank or unless you contract a blood bank to store it for you.
Why store cord blood?
Your baby's cord blood is a valuable sources of stem cells with genetically unique DNA. These stem cells may be used to cure or treat serious and even terminal illness within your family. Keep in mind that even though cord blood is rich in hematopoietic stem cells, cord blood banking has become a controversial topic in prenatal medicine because doctors cannot guarantee that stem cell transplant treatments will cure all illness.
There is no denying that stem cell research offers great advancements in medicine and that by storing the cord blood of your infants, you open windows of opportunity for medical break throughs of the future. However, storing cord blood is very costly. If you're interested in cord blood banking you can find services near you through companies such as ViaCord or LifeBankUSA.
In 2007 the American Academy of Pediatrics stated "Physicians should be aware of the unsubstantiated claims of private cord blood banks made to future parents that promise to insure infants of family members against serious illness in the future by use of the stem cells contained in the cord blood."
Most blood banking companies do offer payment plans for their services. If you are considering cord blood banking visit http://aappolicy.aappublications.org/cgi/reprint/pediatrics;104/1/116.pdf for more objective information from the American Academ of Pediatrics.