Umbilical Venous Volume Flow Research Articles

Abstract 15837: Decreased Placental Blood Flow in Fetuses With Congenital Heart Disease is Associated With Placental Vascular Abnormalities and Impaired Fetal Growth

Introduction: Studies suggest the placenta is abnormal in fetuses with congenital heart disease (CHD), possibly due to shared abnormal vascular developmental pathways. Umbilical venous volume flow (UVVF) is a validated Doppler-derived noninvasive imaging method to assess blood flow from placenta to fetus. We previously demonstrated that mid-gestational UVVF is decreased in fetuses with CHD compared to controls. We hypothesize that decreased UVVF in fetuses with CHD is associated with placental vascular abnormalities as well as impaired fetal growth. Methods: Pregnant women carrying fetuses with CHD (n=38; n=29 single ventricle (SV); n=8 TOF, n=1 d-TGA) or without (n=38) were enrolled in a prospective case-control study. UVVF and combined cardiac output (CCO) were measured during second trimester fetal echocardiograms (echo). Postnatal placentas were analyzed and assigned a placental abnormality severity score (PASS) based on the degree of lesions associated with fetal vascular malperfusion (FVM) and chronic inflammation (CI). Biometrics were collected for all newborns. T-tests or Fisher’s Exact tests were performed to assess statistical significance. Results: Gestational age (GA) at time of fetal echo was slightly greater for the CHD group (Table). All CHD fetuses as well as subgroup analysis of SV only had decreased UVVF indexed to fetal weight (UVVF/Wt) and to CCO (UVVF/CCO). Placental PASS analysis demonstrated higher grade FVM and CI lesions in fetuses with CHD. Fetuses with CHD were born earlier and had decreased birth weight z-scores compared to controls. Conclusions: Fetuses with CHD demonstrate decreased placental blood flow in utero, higher grade placental lesions associated with FVM and CI, and decreased birth weight. UVVF reflects characteristics of abnormal placental pathology and may be a useful marker of placental malperfusion in fetuses with CHD. Future study looking at association of UVVF and clinical outcomes is warranted.

Umbilical Venous Volume Flow in Late-Onset Fetal Growth Restriction.

Umbilical vein flow (UVF) is reduced in fetal growth restriction (FGR). We compared absolute and size-adjusted UVF (estimated fetal weight [EFW] and abdominal circumference [AC]) and rates of abnormal UVF parameters (<10th percentile) among FGR fetuses meeting Delphi criteria (FGR-D) against small for gestational age (SGA) fetuses and appropriate for gestational age (AGA) controls. Absolute UVF, UVF/EFW, and UVF/AC were compared between 73 FGR pregnancies (35 FGR-D, 38 SGA) and 108 AGA controls. Rates of abnormal UVF were compared to abnormal umbilical artery pulsatility index (UAPI). Independent samples t-tests, Mann-Whitney U, odds ratio (OR), chi-squared, and Fisher's exact tests were used as appropriate. Mean absolute UVF was significantly decreased in FGR-D compared to AGA (P=.0147), but not between SGA and AGA fetuses. The incidence of both abnormal absolute UVF and UVF/AC values (<10th centile) was higher among late-onset FGR fetuses versus AGA fetuses (UVF: OR 2.7, confidence interval [CI] 1.37-5.4; UVF/AC: OR 2.73, CI 1.37-5.4). UVF was more frequently abnormal than UAPI and in only two fetuses were both Doppler values abnormal. Absolute UVF is altered in late-onset FGR, and most pronounced among FGR-D. UVF may provide additional insight into fetal compromise in those affected by growth restriction.

Mid-gestational fetal placental blood flow is diminished in the fetus with congenital heart disease.

Data suggest fetuses with congenital heart disease (CHD) have placental abnormalities. Their abnormal placental vasculature may affect fetal placental blood flow, which has not previously been explored. We performed a retrospective cross-sectional study comparing umbilical venous volume flow (UVVF) of single ventricle, D-transposition of the great arteries, and tetralogy of Fallot fetuses with fetuses without CHD. UVVF and combined cardiac output (CCO) were calculated from fetal echocardiography and compared using t tests, χ2 and Fisher's exact tests. Mean gestational age and fetal weight were greater in CHD fetuses (26.5 weeks, 1119.4 g; n = 81, P < .001) compared to controls (23.1 weeks, 675 g; n = 170, P < .001). UVVF/fetal weight was nevertheless decreased among cases (99.8 vs 115.3 mL/min/kg, P < .001). Subgroup analysis of 20- to 25-week fetuses demonstrated no significant differences in case and control baseline characteristics. In CHD fetuses (n = 31) compared to controls (n = 144), absolute UVVF (50.8 vs 62.1 mL/min, P = .006), and UVVF/fetal weight (98.8 vs 118.5 mL/min/kg, P < .001) were decreased. Findings were similar in single ventricle (n = 24) and hypoplastic left heart syndrome (n = 14). Mid-gestational placental blood flow in CHD fetuses is decreased compared to controls. Further study is needed to explore the relationship between UVVF and placental pathology, and impact on outcomes.

The Relationships of Umbilical Venous Volume Flow, Birthweight and Placental Share in Monochorionic Twin Pregnancies With and Without Selective Intrauterine Growth Restriction

This study was conducted to investigate the relationship among umbilical venous volume flow, birthweight and placental share in monochorionic twins with or without selective growth restriction. Having excluded cases complicated with twin-to-twin transfusion syndrome and one co-twin suffering intrauterine fetal death, a total of 51 monochorionic twin pregnancies were divided into two groups as with (group 1) and without (group 2) selective intrauterine growth restriction. Umbilical venous volume flow was calculated by multiplying the umbilical vein cross-sectional area by half of the maximal velocity around mid-trimester. The placentas were cut along the vascular equator into two individual placental masses. The discordance of birthweight was calculated as [(birthweight of larger twin-birthweight of smaller twin)/birthweight of larger twin 100%]. The discordances of umbilical venous volume flow and placental share were calculated in a similar fashion. The median umbilical venous volume flow discordances (68.4% and 15.3% in groups 1 and 2 monochorionic twins, respectively) were similar and correlated well with the placental share discordances (66.6% and 18.5% in groups 1 and 2 monochorionic twins, respectively) but not with the birthweight discordance (28.6% and 6.4% in groups 1 and 2 monochorionic twins, respectively) in both groups. We concluded that the umbilical venous volume flow discordance reflects the placental share discordance rather than the birthweight discordance in monochorionic twin pregnancies.

P06.05: Hemodynamics of fetuses after fetoscopic laser surgery with twin–twin transfusion syndrome

Objectives: The aim of this study was to evaluate hemodynamics in each twin fetuses of twin–twin transfusion syndrome (TTTS) pregnancy after fetoscopic laser surgery. Methods: Over a period of 3 months (June to September 2009) 18 pregnant women underwent fetscopic laser surgery (FLS) for TTTS. We measured umbilical venous volume flow (UVF) dynamics and combined cardiac output (CCO) of both fetuses before FLS and on day 1.4.7.14.21.28 after FLS. Results: All 36 fetuses in 18 cases were alive after FLS. The CCO of both donor and recipient fetuses elevated and achieved a peak within 1–4 days after FLS and decreased to normal level of CCO by one week. Thereafter, the levels of CCO in both fetuses were unchanged until their term. Donor’s UVF achieve a peak within 1–4 days after FLS and decreased to a little higher level than those before FLS. Recipient’s UVF gradually decreased to the normal level without making a peak after FLS. Conclusions: The changes of UVF in donor and recipient demonstrate the alternation of placental circulating blood volume by coagulating the connecting vessels. The increase of CCO in the recipient was not explained by the alternation of placental circulating blood volume by FLS. The dynamics of CCOs in twins following FLS can be caused by a different mechanism. The further study needs to clarify this question.

Changes in umbilical venous volume flow after fetoscopic laser occlusion of placental vascular anastomoses in twin-to-twin transfusion syndrome

To examine effects of fetoscopic laser occlusion of placental vascular anastomoses on umbilical venous volume flow in twin-to-twin transfusion syndrome. Absolute umbilical venous volume flow, measured preoperatively and 48 hours after fetoscopic laser occlusion was related to Doppler studies, bladder filling in donors, and anastomoses. Among 45 patients, recipients had decreased ductus venosus pulsatility index (ductus venosus-pulsatility index for veins, 1.16 vs 1.01; P < .001) and unchanged umbilical venous volume flow after fetoscopic laser occlusion (74.7 vs 74.5 mL; P = .407). Donors had decreased umbilical artery pulsatility (1.34 vs 1.11; P = .008), increased ductus venous-pulsatility index for veins (0.75 vs 0.91; P < .014), and significantly increased umbilical venous volume flow per kilogram by 52.3% (136.6 vs 208.0 mL/Kg/min; P < .001). Donor bladder filling occurred at higher umbilical venous volume flow per kilogram (142.7 vs 221.4 mL/Kg/min; P < .012). Increase in umbilical venous volume flow per kilogram correlated with the net difference in arteriovenous anastomoses (Pearson r = 0.403, P = .006). Fetoscopic laser occlusion in twin-to-twin transfusion syndrome corrects intertwin differences in umbilical venous volume flow by predominant effects in the donor. Reappearance of donor bladder filling correlates with correction of volume flow.

Umbilical venous volume flow in twin–twin transfusion syndrome

To examine umbilical venous volume flow (UVF) dynamics by twin status and disease severity in untreated twin-twin transfusion syndrome (TTTS). In 70 cases of untreated TTTS, absolute UVF, UVF corrected for estimated fetal weight (UVF/kg), intertwin difference (DeltaUVF/kg) and recipient to donor ratio (R/D-UVF/kg) were calculated. Parameters for UVF were compared with respect to twin status and disease severity (early, Quintero Stages I and II; advanced, Stages III and IV). UVF/kg was higher in recipients than in donors and decreased with advancing stage in both twins (in recipients, 183.9 mL/kg/min vs. 145.6 mL/kg/min, P = 0.043; in donors, 137.5 mL/kg/min vs. 122.5 mL/kg/min, P = 0.033). Linear regression analysis demonstrated that the overall best correlation coefficient for DeltaUVF/kg was obtained for the Doppler pulsatility index of the umbilical artery (t = - 4.536, P < 0.001). In advanced stage, absolute and weight-corrected UVF were lower overall, while significant differences in intertwin volume flows persisted. The lowest flows were observed in hydropic recipients (median, 67.0 (range, 55.2-122.0) mL/kg/min vs. 180.8 (range, 59.1-565.4) mL/kg/min; P = 0.001). In TTTS, UVF is significantly higher in recipients than in donors. With progression to advanced stage UVF/kg decreases in both twins as the magnitude of UVF that can be accommodated by the recipient declines. Further study of these dynamics in combination with cardiac performance parameters is warranted to refine diagnostic and prognostic assessment.

Umbilical venous Doppler velocimetry and volume flow in the assessment of growth restricted fetuses in the thrid trimester

Umbilical venous Doppler velocimetry and volume flow in the assessment of growth restricted fetuses in the thrid trimester

Three‐dimensional sonographic assessment of fetal urine production before and after laser surgery in twin‐to‐twin transfusion syndrome

Fetal urine production in twin-to-twin transfusion syndrome (TTTS) reflects the hemodynamic imbalance between the donor and recipient twins but it has not been measured in this particular condition. The aim of this study was to measure fetal urine production using three-dimensional (3D) ultrasound in donor and recipient twins before and after laser treatment for TTTS and to correlate this with umbilical venous volume flow (UVVF). Urine production rate (UPR) was measured using 3D ultrasound with Virtual Organ Computer-aided AnaLysis (VOCAL) in 106 cases of severe TTTS. The rotation angle was set at 30 degrees . The bladder volume was measured twice in each fetus (V(1) and V(2)), with an interval of 5-30 min between measurements, in order to calculate the UPR. When V(2) > V(1), UPR was calculated using the formula: V(2) - V(1) /time interval. Together with UPR, UVVF was measured before and after treatment. Both parameters were corrected for fetal weight. Inter- and intraobserver variability were calculated in 16 cases using the intraclass correlation coefficient. Before laser treatment, UPR was significantly higher in recipients compared with donors (median, 14.8 and 0 mL/h/kg, mean 23.8 and 2.3 mL/h/kg, respectively, P < 0.001), and UPR was positively correlated with UVVF in both twins. Following laser treatment (48 h later), UPR decreased to 9 mL/h/kg (P < 0.001) in recipients, while there was no change in donors. UVVF increased significantly from a median value of 92 to 132 mL/min/kg (P < 0.01) in donors and decreased significantly from 150 to 99 mL/min/kg (P < 0.001) in recipients. In TTTS UPR is correlated to UVVF and reflects the hemodynamic imbalance between donor and recipient twins. Following laser treatment, UPR decreases in recipients but is unaffected in donors. However, changes in UVVF occur in both twins. This suggests that although fetal renal function is driven by fetal hemodynamics, there may be a lag in the recovery of renal function in the donor twin.

Intertwin discordance in umbilical venous volume flow: a reflection of blood volume imbalance in twin‐to‐twin transfusion syndrome

To compare umbilical venous volume flow (UVVF) between donor and recipient twins in twin-to-twin transfusion syndrome (TTTS) using an index that is independent of gestational age and to correlate changes in this index with outcome following endoscopic laser surgery. UVVF was calculated in 84 cases of TTTS by multiplying the umbilical vein cross-sectional area at its entry into the fetal abdomen by time averaged blood velocity. All cases were classified according to the Quintero staging system. The ratio between UVVF in recipients and donors (R/D-UVVF) in each pair of twins was calculated before and 48 h after laser treatment, and changes in R/D-UVVF were correlated with pregnancy outcome. Intraobserver and interobserver UVVF measurement reliability was assessed in 19 singletons, and 13 donor and recipient twins before laser treatment using the intraclass correlation coefficient (ICC). Twenty-five, 32, 21 and six cases presented as Quintero Stages 1, 2, 3 and 4, respectively, at a median gestational age of 20 (range, 15-26) weeks. Intraobserver and interobserver ICC for UVVF measurement in twins were 0.97 and 0.67, respectively. UVVF was a median of 2.13-fold (range, 0.3-19-fold) higher in recipients than in donors (137 mL/min vs. 64 mL/min, P < 0.001) and increased with gestational age (r = 0.58, P < 0.001 for recipients, r = 0.62, P < 0.001 for donors). From 68 cases in which R/D-UVVF could be measured 48 h following laser surgery, cases with a favorable outcome showed a significant decrease in R/D-UVVF from a median of 1.97 to 1.27 (P < 0.01) and cases with recurrent TTTS (n = 6) did not (decrease in R/D-UVVF from a median of 2.32 to 2.19, P = 0.17). Using a cut-off of < 30% reduction of R/D-UVVF, 66% of the cases with recurrence could be predicted, and the odds ratio for recurrence was 3.13 (95% CI, 0.52-18.29). A significant UVVF imbalance between recipient and donor twins was found in cases with Quintero Stages 1-3 but not in those with Stage 4. In TTTS, UVVF is significantly higher in recipients than in their donor cotwins and the R/D-UVVF seems adequately to indicate the flow imbalance between twins, regardless of gestational age. A decrease in R/D-UVVF could be predictive of a favorable evolution following laser treatment.

OC73: Umbilical venous volume flow in untreated and treated twin–twin transfusion syndrome (TTTS)

OC73: Umbilical venous volume flow in untreated and treated twin–twin transfusion syndrome (TTTS)

The fetal circulation and essential organs—a new twist to an old tale

The fetal circulation and essential organs—a new twist to an old tale

Intertwin differences in umbilical venous volume flow in twin to twin transfusion syndrome (TTTS)

number of anastomoses. On day 2 after FLOC UVVF was higher in donor twins with new evidence of bladder filling (73 vs. 43 ml/min, p!0.005). CONCLUSION: Fetoscopic laser ablation of placental vascular anastomoses corrects intertwin differences in umbilical venous volume flow observed in severe TTTS. The predominant effect observed initially is normalization of volume flow in the donor twin. Enhanced bladder filling observed in these circumstances provides a clinicial correlate for successful correction of intravscular volume status. Impacts on the recipient are likely to be more gradual and therefore not detected in the time frame studied.

Fetoscopic laser ablation of placental vascular anastomoses corrects umbilical venous volume flow abnormalities responsible for twin-twin transfusion syndrome

Fetoscopic laser ablation of placental vascular anastomoses corrects umbilical venous volume flow abnormalities responsible for twin-twin transfusion syndrome

P16.12: Quantitative fetal umbilical venous volume flow between 11 and 14 weeks: a pilot study

Objective: Quantitative assessment of fetal venous volume flow can be used in compromised fetuses such as in intrauterine growth restriction. In a pilot study, we explored the feasibility of umbilical venous volume flow ultrasound measurements in fetuses at the time of NT measurement for individual chromosomal risk assessment. Methods: In 26 fetuses the NT was measured and the umbilical venous volume flow quantified non-invasively using ‘‘colour velocity imaging’’ (CVI) in the proximal straight portion of the intraabdominal umbilical vein. Results: All fetuses but four had NT values below the 95th centile (adjusted for crown rump length) of whom one with a mildly increased NT was found to have trisomy 21. All other pregnancies had a normal pregnancy outcome. Quantitative umbilical volume flow as measured by CVI ranged from 5 to 32 mL/min and increased between 11 and 14 weeks’ gestation in a linear fashion. Conclusions: Fetal umbilical volume flow can be measured noninvasively using colour velocity imaging. Umbilical venous volume flow increases between 11 and 14 weeks. One fetus with a mildly increased NT and trisomy 21 showed a normal umbilical volume flow.

OC20.06: Epidemiologic and statistical pitfalls in prediction models for fetal weight estimation

ultrasound units. Thanks to this venous flows in the fetus can be reproducibly measured. Different methodologies are a source of systematic errors, but they do not impair their possible diagnostic usage within centers. Errors due to diameter of the vessel and angle of interrogation of the Doppler beam are in fact limited by the quality of digital imaging. A third source of errors remains the difference between the ideal flow model as perfect parabolic flow and the real flow along any specific fetal vessels. However, while technological researches are ongoing, diagnostic application of volume flow are within reach. Umbilical venous flow can be measured and significant reductions in growth restricted fetuses can be diagnosed and followed. This is the base to understand the redistribution of flow at the liver cross roads. In normal pregnancies the blood shunted by the ductus venosus progressively decreases down to a 20% of the umbilical flow, in severe IUGR fetuses this percentage is dramatically inverted, and mirrored by a parallel ductal a-wave reduction. This inversion can become so sever as to draw blood from the portal sinus into the ductus venosus. Severe liver underperfusion and organ damage is the net result of this changes in flow redistribution. Umbilical and liver venous volume flow qualifies today for a powerful instrument to monitor growth restricted fetuses Similar changes in flow redistribution can be measured at the level of the heart and brain even though arterial flow volume measurements in such small vessels are probably limited by the higher expertise required.

OC20.02: Volume flow estimation

In the last twenty years measurement of fetal volume flow, was perceived as a possible direct insight into the core of pathophysiology, not just how it looks, but how it works. The real limitation was set by expensive research ultrasound machines, and by the expertise of research sonologists, until when high technology digital instruments became the standard of quality commercial ultrasound units. Thanks to this venous flows in the fetus can be reproducibly measured. Different methodologies are a source of systematic errors, but they do not impair their possible diagnostic usage within centers. Errors due to diameter of the vessel and angle of interrogation of the Doppler beam are in fact limited by the quality of digital imaging. A third source of errors remains the difference between the ideal flow model as perfect parabolic flow and the real flow along any specific fetal vessels. However, while technological researches are ongoing, diagnostic application of volume flow are within reach. Umbilical venous flow can be measured and significant reductions in growth restricted fetuses can be diagnosed and followed. This is the base to understand the redistribution of flow at the liver cross roads. In normal pregnancies the blood shunted by the ductus venosus progressively decreases down to a 20% of the umbilical flow, in severe IUGR fetuses this percentage is dramatically inverted, and mirrored by a parallel ductal a-wave reduction. This inversion can become so sever as to draw blood from the portal sinus into the ductus venosus. Severe liver underperfusion and organ damage is the net result of this changes in flow redistribution. Umbilical and liver venous volume flow qualifies today for a powerful instrument to monitor growth restricted fetuses Similar changes in flow redistribution can be measured at the level of the heart and brain even though arterial flow volume measurements in such small vessels are probably limited by the higher expertise required.

The impact of maternal plasma volume expansion and antihypertensive treatment with intravenous dihydralazine on fetal and maternal hemodynamics during pre-eclampsia: a clinical, echo-Doppler and viscometric study.

To establish the effects of plasma volume expansion (PVE) followed by intravenous dihydralazine (DH) administration on maternal whole blood viscosity (WBV) and hematocrit, uteroplacental and fetoplacental downstream impedance and umbilical venous (UV) volume flow in pre-eclampsia. In 13 pre-eclamptic women maternal and fetal hemodynamics were established by means of combined measurement of maternal arterial blood pressure (BP), WBV, hematocrit and uterine artery (UtA) resistance index (RI) in addition to umbilical artery (UA) pulsatility index (PI) and UV volume flow obtained from UV vessel area and UV time-averaged flow velocity. In each woman all parameters were measured four times at baseline, after PVE, after DH and 24 h after the start of treatment. Maternal diastolic BP, hematocrit and WBV display a significant reduction after PVE. In the fetus UA PI decreases significantly whereas a significant increase in UV cross-sectional area was detected. After maternal DH administration, arterial systolic and diastolic BP and UA PI show a significant decrease compared with the measurements following PVE. At 24 h, only maternal systolic and diastolic BP display a significant further decrease. No significant changes were established for the UtA RI, UV time-averaged velocity and UV volume flow during the entire study period. During pre-eclampsia, maternal PVE followed by DH administration results in a significant reduction in maternal diastolic BP, maternal hematocrit and WBV. Maternal PVE is associated with a significant increase in UV cross-sectional area and a non-significant rise of 11% in UV volume flow. Maternal DH administration does not result in any change in UV cross-sectional area. However, UA PI decreases significantly after both PVE and DH treatment.

Umbilical venous volume flow and fetal behavioral states in the normally developing fetus

To determine the relationship between umbilical venous (UV) volume flow and fetal behavioral states 1F (quiet sleep) and 2F (active sleep) in normal pregnancies at 36-40 weeks of gestation. Fetal behavioral states were established in 17 normal pregnancies by means of combined assessment of fetal heart rate patterns (FHRP), and fetal eye and body movements. UV vessel area (mm(2)) as obtained by tracing the inner vessel area using Labview and Imaq Vision software and UV time-averaged flow velocity (mm/s Doppler) were multiplied to calculate UV volume flow (mL/min) including flow/kg fetus. The pulsatility index (PI) in the umbilical artery was also determined. In each woman, all parameters were measured between three and five times in each behavioral state. Data are reported as mean +/- 1 SD and analyzed by paired t-test. No statistically significant behavioral-state-related changes were observed for UV time-averaged velocity and UV volume flow, resulting in UV volume flow/kg fetus of 69.1 +/- 14.9 mL/min*kg at 1F and 71.6 +/- 12.1 mL/min*kg at 2F (not significant). A statistically significant increase (P = 0.02) was established for UV cross-sectional area (46.4 +/- 8.6 mm(2) vs. 49.0 +/- 10.1 mm(2)) and for fetal heart rate (FHR) from 134.2 +/- 10.3 bpm in 1F to 144.2 +/- 7 bpm in 2F. Umbilical artery PI was not significantly different between the two behavioral states. On the basis of high venous vessel wall compliance, the significant increase in UV cross-sectional area during fetal behavioral state 2F may be determined by a rise in mean venous pressure. The significant rise in FHR may reflect increased fetal cardiac output during state 2F while the resistance at the hepato-ductal pathway remains relatively constant with the purpose of meeting raised energy demands during the active sleep state. This is further supported by the observed trend towards an increase in UV volume flow.

Assessment of fetal liver volume and umbilical venous volume flow in pregnancies complicated by insulin‐dependent diabetes mellitus

To determine fetal liver volume and its relation with umbilical venous volume flow and maternal glycosylated haemoglobin (HbA1c) in pregnancies complicated by diabetes mellitus type I. A cross sectional matched control study. Obstetric out patient clinic, Erasmus MC-University Medical Centre, Rotterdam. Data from fetuses of diabetic women (n = 32; 18-36 weeks) were compared with data from normal controls (n = 32) matched for gestational age. Umbilical venous cross sectional area (mm(2)) and time-averaged velocity (mm/s Doppler) were determined for calculation of volume flow (mL/min) and flow per kilogram fetal weight (mL/min/kg). Umbilical artery pulsatility index was determined. Fetal liver volume measurements were obtained using a Voluson 530-D. Fetal liver volume, umbilical venous volume flow and downstream impedance. A statistically significant difference between fetuses of diabetic women and normal controls was found for liver volume (mean [SD]: 45.9 [34.0] vs 38.3 [28.7] mL), abdominal circumference (22.2 [6.6] vs 21.3 [5.6] cm), estimated fetal weight (1162 [898] vs 1049 [765] g) and fetoplacental weight ratio (0.22 vs 0.19) and liver volume/estimated fetal weight ratio (4.13% [0.007] vs 3.62% [0.009]). Umbilical venous volume flow (mL/min) and umbilical artery pulsatility index were not essentially different between the two study groups, but umbilical venous volume flow per kilogram fetal weight was lower (P < 0.05) in the diabetes group (94.3 [26.1] mL/min kg) compared with normal controls (109.5 [28.0] mL/min/kg). A positive correlation existed between fetal liver volume and maternal HbA1c (P = 0.002). Measurement of fetal liver volume by three-dimensional ultrasound may play a role in identifying fetal growth acceleration in diabetic pregnancies. Fetal liver volume increase is positively related to maternal HbA1c levels reflecting degree of maternal glycemic control. Fetal liver volume normalised for estimated fetal weight is significantly higher in the fetuses of diabetic women. In the present study, umbilical venous volume flow and fetoplacental downstream impedance are not different between diabetic and normal pregnancies.