A. Padoan

Small size‐specific umbilical vein diameter in severe growth restricted fetuses that die in utero

To study changes in umbilical vein (UV) blood flow velocity, diameter and blood flow volume in intrauterine growth retardation (IUGR) fetuses who die in utero (IUD‐IUGR).

OP15.01: Absolute uterine artery blood flow volume is increased in twin human pregnancies compared to singletons

Objectives: To compare (1) absolute and (2) weight-specific blood flow volume of uterine arteries (UtA) in normal twin pregnancies to normal singleton pregnancies. Methods: Twelve twin pregnancies (10 dichorionic, two monochorionic) with normal UtA PI and normal weight at birth were included. UtA diameter and time-averaged maximum velocity were obtained to calculate flow (mL/min) and UtA flow/EFW (mL/min/kg) in each UtA. UtA flow was estimated by the formula Q = hV · πD2/4; a patient-specific coefficient, h, was obtained by an ad hoc mathematical model. Total UtA flow was calculated as a sum of right and left vessel flow volume. Twins’ UtA flow was expressed per unit EFW considering the sum of the two EFWs. Twins were compared to 48 normal age-matched singletons. Results: Gestational age at exam was similar in twins and in singletons (25.9 ± 6.4 vs. 25.2 ± 6.2 weeks, NS). UtA flow (mL/min) was significantly increased in twins (509.3 ± 240.7 mL/min) compared to singletons (337.2 ± 257.0 mL/min) (P = 0.04). UtA flow (mL/min) exponentially increased along gestation in twins and in singletons. The twins’ trend was above the third interquartile range of singletons’ reference values. UtA diameter was significantly increased in twins (0.33 ± 0.07 cm) than in singletons (0.28 ± 0.05 cm), while no differences in UtA mean velocity were observed (77.5 ± 29.9 vs. 76.7 ± 29.1 cm/sec, respectively, NS). UtA flow per EFW did not differ between twins and singletons (384.4 ± 198.6 vs. 460.9 ± 302.9 mL/min/kg, respectively, NS). Conclusions: (1) UtA flow volume (mL/min) in twin pregnancies was significantly increased. This was determined by larger vessel diameter, compared to singletons. (2) Each twin proved to share an amount of UtA flow per unit estimated fetal weight not significantly different from singletons.

OP01.06: Reduction of uterine artery blood flow volume is correlated to reduced fetal mass in pregnancies with abnormal uterine resistance index

Total vascular resistance (dyne s/cm5) 1623 (1287–3125) 1163 (944–1785) 0.008 Stroke volume (mL) 69 (36–81) 67 (57–86) 0.95 Cardiac output (L/min) 5.40 (4.4–7.0) 6.1 (4.0–8.1) 0.08 Ejection fraction (%) 69 (64–83) 71 (65–79) 0.59 Midwall fractional shortening (% of predicted value) 118 (94–126) 122 (106–140) 0.04 Isovolumetric relaxation time (ms) 78 (50–90) 60 (45–75) 0.006 24 h ambulatory heart rate (bpm) 74 (61–82) 79 (76–92) 0.003 24 h ambulatory systolic blood pressure (mmHg) 117 (104–136) 106 (101–121) 0.031 24 h ambulatory diastolic blood pressure (mmHg) 75 (65–88) 66 (56–73) 0.012 24 h ambulatory mean arterial pressure (mmHg) 87 (79–104) 79 (72–87) 0.016

P07.05: Uterine artery blood flow volume growth rate in uncomplicated human pregnancies

Objective: 1) To study uterine artery (UtA) flow (ml/min) growth rate along gestation in normal human pregnancies; 2) to evaluate longitudinal changes of UtA flow expressed per unit estimated fetal weight (EFW) (ml/min/kg). Methods: A cohort of twelve singleton uneventful human pregnancies, with a normal mean UtA PI, was included in this longitudinal study. UtA was evidenced by power-Doppler mode and sampled 10–15 mm prior to bifurcation. UtA diameter was measured on a perpendicular view after removing power-Doppler. UtA PI and velocity were measured with a Doppler beam angle < 30◦. The average of three consecutive diameters and velocities was considered. UtA flow was estimated by the formula Q = hV · πD2/4; h coefficient (0.5) was obtained by an ad hoc mathematical model. UtA total flow (ml/min) (right plus left UtA flow) was then expressed per EFW (ml/min/kg). Using linear interpolation, including random effects for the intercept and the slope of gestational age for each fetus, a linear mixed effects model was fitted. Results: Forty-seven ultrasound examinations were performed. Ultrasound exams were performed at 14.3,b1.2 weeks and every 4 weeks until delivery. Each case was definitively included in the study after recording normal perinatal and neonatal outcomes. UtA total flow (ml/min) showed a significant correlation to gestational age (133.6 ml/min at 15 weeks; 415.9 ml/min at 35 weeks) (p < 0.001), with a linear increase of 14.1 ml/min per week (right UtA 5.4 vs. left UtA 8.7 ml/min per week, p NS). UtA flow per unit EFW (ml/min/kg) showed a significant reduction from 780.3 ml/min/kg at 15 weeks to 144.1 ml/min/kg at 35 weeks (reduction rate 40.3 ml/min/kg per week). Conclusions: UtA flow (ml/min) significantly increased along gestation in this longitudinal cohort of normal pregnancies. UtA flow per unit EFW (ml/min/kg) significantly decreased longitudinally, since UtA flow (ml/min) growth rate was lower than fetal weight gain rate along gestation.

OP13.11: Uterine artery blood flow volume: ranges in uncomplicated human pregnancies

towards term. The peak-systolic velocity increased from mean 59 to 71 cm/s during the weeks 21–31 and remained stable until term. The diastolic velocity showed a continuous increase from 31 cm/s at 21 weeks to 43 cm/s at 40 weeks. The pulsatility index for veins decreased from 0.57 at 21 weeks to 0.44 at 40 weeks. Terms for individually conditioned observations modify the reference ranges when used for serial measurements. Conclusion: The new reference ranges reflect the development of the ductus venosus blood velocities and velocity indices during the second half of pregnancy and are thus appropriate for the serial measurements required when monitoring growth-restricted fetuses.

OP10.08: Is uterine artery blood flow volume correlated to placental site in normal human pregnancies?

one case was lost to follow-up. Of the remaining 16 pregnancies, 15 women delivered at term and all the infants were healthy. The remaining case delivered a stillborn fetus at 28 week due to an E. coli intrauterine infection. The cause of death was considered unrelated to the PSC. Discussion: According to this series, PSCs are associated with a good perinatal outcome. In contrast with umbilical cord cysts, it is unlikely that PSCs can jeopardize fetal wellbeing, despite continuous growth during pregnancy in some of them. Owing to the close proximity to the umbilical cord in most cases, PSCs should be clearly differentiated from umbilical cord cysts, which carry a poorer prognosis.

P07.04: Uterine artery blood flow volume is reduced in human pregnancies with increase utero‐placental downstream impedance

Objectives: To assess the predictivity of first-trimester uterine artery Doppler measurements for pre-eclampsia. Methods: Uterine artery Doppler findings were prospectively obtained at 11–14 weeks in 3100 singleton pregnancies. Preeclampsia was defined as a blood pressure > 140/90 mmHg, and proteinuria of ≥ 300 mg in 24hrs, or two readings of at least 1+ on dipstick analysis of midstream or catheter urine specimens if no 24-hour urine collection was available. Results: There were 54 cases of pre-eclampsia (1.7%), for 16 of which (0.5%) delivery before 37 weeks was necessary. Sensitivity and specificity of different cut-offs of uterine resistance index (RI), pulsatility index (PI), bilateral diastolic notches, and their combinations for the prediction of pre-eclampsia are shown in the Table.

OC27.05: Human uterine artery blood volume flow at mid‐gestation: relationship to uterine artery Doppler velocimetry and placental site

intraventricular hemorrhagia and elevated nucleated red blood cell counts at delivery. Results: 8 stillbirths (10.7%), 12 perinatal (16%) and 2 neonatal death (2%) occurred among 74 fetuses. Logistic regression analysis confirmed that abnormal Ductus venosus waveforms (R2 = 0.57, p < 0.001) together with gestational age (R2 = 0.57, p < 0.001) showed the strongest association with perinatal death, whereas gestational age only was significantly related with neonatal death (R2 = 0.67, p < 0.05). Abnormal ductus venosus Doppler waveforms (R2 = 0.86, p < 0.001) and gestation age (R2 = 0.49, p < 0.05) were strongly associated with adverse outcome. Abnormal venous Doppler flow patterns performed better in the prediction of fetal or perinatal demise than died ARED flow or brain sparing. Conclusion: Abnormal Ductus venosus waveforms in preterm growth-related fetuses with ARED flow are strongly relates to adverse fetal and perinatal outcomes below 32 weeks of gestational age. The possible benefit of these pregnancies to be prolonged can only be evaluated in a prospective randomized study.

OC20.02: Volume flow estimation

Results: Of the 31 patients with posterior deep pelvic endometriosis, 20 were scheduled for surgery and 11 for MRI and medical treatment. A comparison between TVS, TRS, vaginosonography and laparoscopy or MRI was performed. The concordance rate in the diagnosis of endometriotic nodes of the pouch of Douglas and uterosacral ligaments was similar for TVS and TRS 90% and 91% respectively. Whereas the accuracy in the diagnosis of rectovaginal nodes, in particular for those infiltrating the rectal wall and vaginal fornix, is higher with TRS and vaginosonography (94%). Conclusions: TRS and vaginosonography may provide accurate informations about the presence and the extension of posterior deep endometriosis. In particular it improves the diagnosis of the infiltration of the rectal wall and vaginal fornix and could be useful in the management and counseling of these patients and to guide the surgeon’s laparoscopic approach.