[Ultrasound studies of blood flow in the umbilical vein].
The umbilical vein blood flow was examined in a total of 101 healthy pregnant women in 146 occasions between the 28th and 41st weeks of pregnancy. A Kranzbühler 8130 Duplex Doppler machine was used in all of the examinations. It was found that the blood flow is near to the same value (120 ml/min/kg) till the 37 to 38th weeks of pregnancy during the third trimester, then decreases continuously and is about 90 ml/min/kg on the 41st week of pregnancy. The diameter of the umbilical vein increases from 4-5 mm to 6-7 mm, but the rate of growth slows down after the 36-37th weeks. The velocity of the blood flow between the 28th and 41st weeks of pregnancy fluctuates between wide limits (10-24 cm/s), but a slight decrease could be observed from the 36-37 weeks of pregnancy.
D000293:Adolescent; D000328:Adult; D001783:Blood Flow Velocity; D005260:Female; D006801:Humans; D008431:Maternal-Fetal Exchange; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D012212:Rheology; D014463:Ultrasonography; D014471:Umbilical Veins / Q000502:physiology*
Ultraschalluntersuchungen des Blutdurchflusses der Vena umbilicalis.