D.S. Pares

OP23.04: First trimester evaluation of the ductus venosus: influence of body mass index and gestational age

late samples. Age standardised detection and false positive rates for different screening protocols were produced. Results: We collected two blood samples in 27 pregnancies affected by trisomy 21 and in 3891 control pregnancies. The early samples were taken between gestational week 8+0 up to week 13+6, and the late samples between week 11+3 up to week 14+6. The median interval between the samples was 17 days (range 1–40 days). We found a significantly better (P < 0.05) estimated screening performance when using early sampling vs. late sampling. With a risk cut-off of 1 in 100, at the time of the risk assessment, the estimated detection and false positive rates were 91% (95% CI: 81–98%) and 1.6% (95% CI: 1.3–2.0%) respectively. Better estimated performance was achieved with the use of the double set of markers; detection rate 93% (95% CI: 85–99%) and false positive rate 1.7% (95% CI 1.4–2.0%), but this was not significantly different from the early sample protocol (P > 0.05). Conclusions: Using early sampling with measurement of PAPPA and free β-hCG in the combined first trimester screening can optimise screening performance for trisomy 21. Using a double set of the maternal serum markers has the potential to further improve screening performance.

P07.08: First trimester evaluation of the tricuspid flow: influence of body mass index and gestational age

Objectives: To estimate whether body mass index (BMI) and gestational age (GA) affects the evaluation of the tricuspid flow (TF) during first-trimester ultrasound examination for aneuploidy risk assessment. Methods: Using a Medison SA-8000Live system and an abdominal probe, we evaluated 519 women with singleton pregnancies undergoing first-trimester aneuploidy risk assessment ultrasound examinations. Weight categories were defined as normal (BMI less than 25), overweight (25–29.9), obese (30–34.9) and severely obese (more than 35). Gestational age categories were defined in week intervals from 11 to 14 weeks. The evaluation of the TF was considered inadequate when after 20 minutes a waveform displaying the Fetal Medicine Foundation criteria was not obtained. Results: Increasing BMI was associated with inadequate TF assessment. Table 1 displays the percentage of patients where the TF assessment was inadequate. As to GA, the percentage of patients with inadequate TF assessment decreased in higher GA groups, as displayed in Table 2. Conclusions: In singleton pregnancies, increased BMI was associated with a lower likelihood of obtaining an adequate TF waveform. Gestation age also affects the assessment of the TF. Exams performed with GA ≥ 12 weeks were associated with a higher likelihood of obtaining an adequate TF waveform.

P07.09: First trimester evaluation of the facial angle: influence of body mass index and gestational age

Objectives: To estimate whether body mass index (BMI) and gestational age (GA) affects the evaluation of the tricuspid flow (TF) during first-trimester ultrasound examination for aneuploidy risk assessment. Methods: Using a Medison SA-8000Live system and an abdominal probe, we evaluated 519 women with singleton pregnancies undergoing first-trimester aneuploidy risk assessment ultrasound examinations. Weight categories were defined as normal (BMI less than 25), overweight (25–29.9), obese (30–34.9) and severely obese (more than 35). Gestational age categories were defined in week intervals from 11 to 14 weeks. The evaluation of the TF was considered inadequate when after 20 minutes a waveform displaying the Fetal Medicine Foundation criteria was not obtained. Results: Increasing BMI was associated with inadequate TF assessment. Table 1 displays the percentage of patients where the TF assessment was inadequate. As to GA, the percentage of patients with inadequate TF assessment decreased in higher GA groups, as displayed in Table 2. Conclusions: In singleton pregnancies, increased BMI was associated with a lower likelihood of obtaining an adequate TF waveform. Gestation age also affects the assessment of the TF. Exams performed with GA ≥ 12 weeks were associated with a higher likelihood of obtaining an adequate TF waveform.

OP03.01: A critical review of the benefits and limits of MRI as a complementary method for the diagnosis of fetal malformations

Down syndrome risk. Of the 56 cases of trisomy 21 (1,2%), 25 were males and 31 females (P = 0,74). Detection rate for trisomy 21 was 84% in males and 87% in females (P=0,8). Free beta HCGMoM, NTMoM and PAPPAMoM were not significantly different between male and female trisomy 21 fetuses. Conclusions: There is a trend towards female fetuses having a higher chance of increased risk at the combined test. There are no gender differences in the detection rate of trisomy 21. Whether risk assessment protocols need to become gender specific needs further investigation.

P09.08: A rare case of dicephalus twins. The importance of the use of tridimensional ultrasound for the parents

gradient light mode, minimum mode, inversion mode, glass body, and color modes. Results: 3D and 4D ultrasound evaluations were performed on 16 fetuses with mean GA 22 weeks (range 14–34). Anomalies included congenital diaphragmatic hernia (two with right sided hernia and one left sided), lung dysplasia (6 cases, of who three had vascular anomalies and three without vascular anomalies), and Thanatophoric dysplasia with small thorax (2 cases), dextrocardia (2 cases), Hydrothorax (1 case), situs inversus totalis (1 case), and situs ambiguous with asplenia (1 case). Conclusion: 3D and 4D techniques are new modalities, which enables higher accuracy, and better views of the fetal thoracic organs and assist the physician in diagnosis the malformations. Performing 3D ultrasound enhances visualization, identification and delineates more clearly the extension of the defect. 3D ultrasound seems to be a promising new tool for precise anatomical description of fetal thoracic organs.

P09.06: Pregnancy outcome in Rh alloimmunized patients managed through amniotic fluid spectrophotometry or Doppler ultrasonography of the fetal middle cerebral artery

Objectives: Compare perinatal results of Rh alloimmunized pregnancies managed with spectrophotometric amniotic fluid (SAF) analysis or Doppler ultrasonography of the fetal middle cerebral artery. Methods: Descriptive observational study with a control group. The study involved 291 consecutive Rh-negative pregnant women examined between January 1995 and January 2004. Patients were divided in three groups: 74 isoimmunized women who were submitted to SAF to evaluate fetal anemia (study group S); 25 isoimmunized women managed with fetal middle cerebral artery Doppler ultrasonography (study group D) and 192 unimmunized patients who served as a control group (normal group – N). Obstetric and neonatal variables analyzed were: intrauterine transfusion, mode and timing of delivery, birthweight, need for neonatal transfusion, neonatal hematocrit and perinatal mortality. Conclusions: Patients managed with SAF or with Doppler had similar rates of intrauterine transfusions and cesarean sections. Approximately 40% of the alloimmunized patients delivered prematurely and one third of their infants weighed less than 2500 g. Infants managed with Dopplervelocimetry had higher hematocrit and less need for neonatal transfusion, suggesting this protocol may best preserve the neonate. Management of fetal anemia through SAF or Doppler did not influence perinatal mortality rate.