Fetal left brachiocephalic vein diameters in normal and growth restricted fetuses.

Objectives: To develop a nomogram for fetal left brachiocephalic vein (LBCV) diameters during a healthy pregnancy and to assess LBCV values in fetuses with fetal growth restriction (FGR).

Methods: This prospective observational study included 31 FGR pregnancies and 438 low-risk pregnancies. The low-risk group was used to determine the 5th, mean, and 95th percentiles for the LBCV between 12 and 39 weeks of gestation based on gestational age. On growth charts, LBCV measurements of FGR fetuses were displayed, and those above the gestational age 95th percentile were considered wide vein. Cerebroplacental ratio (CPR) and umbilical artery (UA), middle cerebral artery (MCA), and ductus venosus (DV) Doppler parameters were evaluated in FGR fetuses.

Results: LBCV diameter increased significantly with advancing gestational age. The LBCV diameters were above the 95th percentile in 23 of the 31 FGR fetuses (74.2%). All fetuses (15/15, 100%) with early-onset (EO)-FGR and 8 fetuses (8/16, 50%) with the late-onset (LO)-FGR had LBCV values above the 95th percentile (p<0.01). UA-PI was significantly higher and MCA-PI and CPR were significantly lower in LO-FGR fetuses with LBCV diameters above the 95th percentile (p<0.05).

Conclusions: LBCV diameters of fetuses with FGR were significantly wider than the normal population. In the LO-FGR group, there was a good correlation between LBCV diameter and CPR.