How Much Blood Is Collected from the Umbilical Cord?
Cord blood collection volume varies meaningfully from birth to birth, and the amount matters — both public and private banks use volume and cell count to decide whether a sample is bankable.
The typical range
A standard cord blood collection yields roughly 60 to 150 milliliters of blood, with an average around 80–110 mL. Public banks usually require a minimum total nucleated cell (TNC) count of around 9 × 10⁸ for the unit to be added to the registry, which generally corresponds to at least 75–80 mL of collected blood. Private banks accept smaller volumes — they'll store the sample even if it falls below transplant-grade thresholds.
What changes the volume
- Gestational age — full-term babies yield more than preterm
- Birth weight — larger babies generally mean larger placentas and more blood
- Delayed cord clamping — reduces collected volume by transferring blood to the baby
- Mode of delivery — vaginal deliveries typically yield slightly more than C-sections
- Timing of collection — quicker collection after clamping captures more
- Whether the placenta is collected in utero or ex utero
What happens if the volume is low
Public banks discard or redirect low-volume units to research rather than the transplant registry. Private banks will still store low-volume samples but should be transparent that the unit may not be transplant-grade for an adult, who needs roughly 25 million nucleated cells per kilogram of body weight. Low-volume samples can still treat a child or be used in regenerative medicine research.
Frequently asked
›Will my baby lose blood from cord blood collection?
No. Collection happens after the cord is clamped and cut, so the blood being collected is what remains in the umbilical cord and placenta — it's not coming from the baby.