N. Hart

Weight estimation by three‐dimensional ultrasound imaging in the small fetus

To improve birth weight estimation in fetuses weighing ⩽ 1600 g at birth by deriving a new formula including measurements obtained using three‐dimensional (3D) sonography.

Increased Accuracy of Fetal Weight Estimation with a Gender-Specific Weight Formula

Objective: To test whether Schild’s sex-specific formula for estimating fetal weight is more accurate than commonly used regression formulae. Methods: The gender-specific formula and 10 widely used equations were evaluated in a group of 989 pregnancies. Each fetus underwent ultrasound examination with complete biometric parameters within 7 days before delivery. Results: Over the whole weight range and in the subgroup of newborns with a birth weight between 2,500 and 3,999 g, the sex-specific weight formula from Schild demonstrated the best level of accuracy. For infants with a birth weight of less than 2,500 g as well as for macrosomic newborns, the gender-specific formula did not improve fetal weight estimation. Conclusion: In pregnancies where fetal gender is known, Schild’s regression formula should be used when fetal weight lies within the range of 2,500–3,999 g.

Gender-Specific Weight Estimation of Fetuses between 2,501 and 3,999 g – New Regression Formulae

Objective: To develop new gender-specific regression formulae to estimate fetal weight focusing on a particular weight range from 2,501 to 3,999 g. Methods: 3,254 singleton pregnancies were included to generate new regression formulae for female and male fetuses, and to evaluate their accuracy. Results: In comparison with commonly used formulae, the new gender-specific and weight-range-specific method of fetal weight estimation provided greater accuracy. The mean absolute error was less than 7%. Conclusions: When properly used, the new formulae can improve the accuracy of weight estimations in fetuses between 2,501 and 3,999 g.

Fetal Adrenal Haemorrhage – Two-Dimensional and Three-Dimensional Imaging

A case of prenatal adrenal haemorrhage first detected by 2-dimensional and 3-dimensional sonography at 27 weeks’ gestation is reported. Ultrasound examination showed a large cystic mass (32 × 27 × 27 mm) in the right suprarenal region of the fetus. Two weeks later, the mass had slightly increased in size demonstrating hyperechoic areas within the cyst. Further serial ultrasound examinations revealed a progressive organisation of the cystic mass associated with a moderate reduction in size. The diagnosis of adrenal haemorrhage was confirmed by postnatal follow-up sonograms as the mass decreased in size from 28 × 21 × 21 mm on day 1 to 23 × 18 × 17 mm on day 42. Course and sonographic signs were typical for adrenal haemorrhage and the neonate was therefore managed without surgical exploration. The child is developing normally at 6 months of age.

Sex‐specific differences in the concentration of tubular parameters in the amniotic fluid of second trimester fetuses

Renal dysplasia and obstructive uropathy are more common in males and are associated with an increased tubular loss of electrolytes. We aimed to compare the midtrimester concentration of tubular parameters in the prenatal period between healthy male and female fetuses.

OC16.01: Correlation between second trimester 3D‐placental volumetry and vascularization, cytokines in the amniotic fluid and fetal weight at birth

Objective: The septate uterus is associated with a decreased live birth rate. The mechanisms by which septate uteri cause early pregnancy loss and infertility have not been completely established yet. Evaluation of septate uterus is quite easy by means of transvaginal three-dimensional (3D TVS) ultrasound. The aim of this study was to assess by 3D TVS uterine septum dimensions, volume, morphology and vascularization and to correlate these features to reproductive outcome. Methods: Patients of reproductive age with a septate uterus underwent 3D TVS. On 3D TVS coronal view of the uterus, septal length and width, volume, echostructure and vascularization by means of the Vascularisation Index (VI), were evaluated. The number of pregnancies and the reproductive outcome of each patient were recorded and correlated to the previous mentioned 3D TVS features. Results: Among 65 patients with septate uterus, 19 had a recurrent pregnancy loss, 5 had a preterm delivery, 4 had a term delivery and 36 presented with primary infertility. The width of the septum was significantly larger in patients with recurrent abortion (31.6 + 6.10mm) compared to those with primary infertility (25.6 + 7.12mm). 3D TVS showed that vascularization expressed as VI calculated on septal volume (17.49 ± 8.40%) was significantly higher in patients with term or preterm deliveries Conclusions: 3D TVS allows detection of different types of uterine septa. The different morphology of uterine septa suggests that the pathogenesis of infertility in these patients is multifactorial, and perhaps the reproductive outcome can be correlated to septal width and structure.

OP38.02: Association between birth weight and second trimester 3D placental volumetry, intraplacental vascularization and amniotic fluid cytokines

The Doppler changes and pregnancy outcomes were analyzed with independent sample t-test, Fisher’s exact test and Pearson’s correlation using the SPSS statistical software (version 12.0; SPSS Inc, Chicago, IL). Results: Twenty one patients with myomas and 30 normal patients were enrolled in this study. The RI and S/D ratio of the uterine artery on both sides were not differ in the myoma group and in control group (P = 0.42, P = 0.15, P = 0.29, P = 0.12, in Right RI, Left RI, Right S/D, Left S/D, respectively). In patients with right side dominant myoma and with left side dominant myoma, the uterine artery Doppler RI and S/D ratio were not differ significantly (P = 0.65, P = 0.22, P = 0.39, P = 0.28, in Right RI, Left RI, Right S/D, Left S/D, respectively). Age is significantly higher in the myoma group (P = 0.03), but there were no differences in gestational age at birth, birth weight, five minute APGAR score, Cesarean section due to fetal distress and neonatal intensive unit care (P = 0.62, P = 0.20, P = 0.08, P = 0.99, P = 0.10, respectively). Conclusions: According to this study, the presence of myoma as well as the location and the size of myoma didn’t change the uterine artery Doppler velocimetry and didn’t affect the pregnancy outcome. Cesarean section or early delivery due to large myoma could be reserved in prenatal management. Further study with a larger study population would be needed for better outcome.

OP10.06: Influence of second trimester placental volume, shell volume and intraplacental circulation on birth weight

Objectives: Nowadays Mode B ultrasound biosafety is not been currently questioned. Instead Doppler mode has not yet reached the same security fee, most probably due to the small number of studies on the topic or that the ones available are not conclusive about harmlessness. Moreover, ISUOG requires all informed patients consent, for every study that includes first trimester Doppler. To determine whether color and pulsed Doppler exposure of rat embryos at different gestational ages could modify any anatomic or clinical parameter. Methods: In a first stage 4 animals of different gestational ages (n = 42 fetuses) were exposed to Doppler during different periods of time. During a second stage two different groups of 8 rats each were used: a) 8 days of gestational age (early ultrasound or EU; n = 68 fetuses), 15 minutes during 4 consecutive days, b) 15 days of gestational age (late ultrasound or LU; n = 45 fetuses) under the same conditions. All ultrasound exposures were done by two or three operators using a Sonoace 8800 Digital Gaia (Medison ultrasound system) ultrasound machine with a 7 MHz lineal transducer. The evaluated parameters were: total number of offspring (alive and dead), gestational age, weight at 2 and 21 days of life, clinical parameters of neuronal development, reproductive capacity. Pathological studies were performed to a group of fetuses obtained by Cesarean section. Results: During the first stage no congenital abnormalities were observed related to Doppler exposure. These animals, exposed during the fetal period, did not show any alteration in their reproductive capacity. During the second stage neither congenital abnormalities nor pathological events were observed. The only statistical significant result (P < 0.001) was a reduction in weight of animals that belong to UL group and at out breeding (day 22), compared to control animals. Conclusions: These results reinforce the necessity to continue studying about the harmlessness of the method.

OC24.05: Increased concentration of tubular parameters in the amniotic fluid of male fetuses in the 2nd trimester of pregnancy

13.53◦ (95% CI: 13.28◦–13.78◦, 5th–95th percentile: 10.4◦–16.9◦). In 22 fetuses with facial clefts (median gestational age: 23 weeks, range: 19+1–29+6 weeks) the mean MNM was 20.6◦ (95% CI: 18.2◦–23.0◦). In all fetuses (n = 3) with intact alveolar ridge the MNM angle was normal. In 13 fetuses with unilateral interruption of the alveolar ridge the MNM angle was above the 95th percentile in 62% (n = 8) and normal in 38% (n = 5) of the cases. In all (n = 6) fetuses with bilateral interruption of the alveolar ridge the MNM angle was above the 95th percentile. Conclusions: The MNM angle can quantify the amount of maxillary protrusion in fetuses with facial clefts. A MNM angle above the 95th percentile indicates an (at least unilateral) interruption of the alveolar ridge.

OP10.06: First trimester 3D‐placental volumetry is a good predictor of both low and high birth weight

Objective: The extremes of fetal weight are associated with serious perinatal complications and increased morbidity and mortality of the newborn. Early pathological changes in the placenta with reduction of its size and increase in uterine blood flow resistance may be of clinical relevance in intrauterine growth restriction but not in macrosomia. We therefore investigated whether placental volume parameters as assessed by 3D-ultrasound in the first trimester are related to fetal weight at birth. Methods: Inclusion criteria were: singleton pregnancy and gestational age between 11 + 0 and 13 + 6 weeks. Exclusion criteria were: smoking, pre-existing diabetes, fetal anomalies, serious maternal disease and maternal medication affecting fetal growth. In 236 patients fetal biometry with regard to crown-rump-length (CRL), biparietal diameter (BIP) and abdominal circumference (AC) and placental volumetry by 3D-ultrasound were routinely performed. The placental volume (PV) and three different placental ratios (PR1=PV/CRL; PR2=PV/BIP; PR3=PV/AC) were calculated. Fetal birth weight below the 10th (SGA) and above the 90th percentile (macrosomia) served as primary outcome variables. Statistics were based on linear and logistic regression analysis. Results: 8.5% of our newborns were SGA and 11.9% macrosomic. The median of first trimester PV was 59.73 cm3. PV (p=0.001) and PR1-3 (p<0.0001) were significantly correlated with fetal weight at birth. In linear regression analysis highly significant effects on fetal birth weight were shown for all placental volume parameters. PV and placental ratios significantly predicted fetal birth weight below the 10th and above the 90th percentile in a logistic regression model. Conclusions: Different placental volume parameters in the first trimester show a strong correlation with fetal birth weight. 3Dplacental volumetry appears to be a useful technique in the early identification of pregnancies at risk for being SGA and macrosomic at birth.