How is umbilical cord blood puncture performed?
Disease description:
I am 20 weeks pregnant, and my Down syndrome screening test results were abnormal. My doctor recommended cordocentesis—could you please explain how it is performed?
Doctor's answer (1)
Dr. Wang Dan
Cordocentesis involves the following steps: First, routine blood tests and coagulation studies must be completed. In addition, ultrasound is used to assess the feasibility of cordocentesis, and informed consent must be obtained from the family after thorough counseling. Under real-time ultrasound guidance, the fetal position is confirmed, and a needle is inserted into the umbilical vein—typically at the insertion site of the umbilical cord into the fetal abdomen—to aspirate 1–5 mL of umbilical blood for diagnostic testing. Following the procedure, the mother and fetus are monitored for 30–60 minutes, and a follow-up ultrasound is performed to evaluate fetal well-being and growth.
