B. Yazdi

Idiopathic polyhydramnios and postnatal abnormalities.

Objective: To investigate the proportion and type of fetal anomalies that are associated with polyhydramnios and to examine whether in cases with idiopathic polyhydramnios during the course of pregnancy and fetal anomalies only diagnosed after birth, antenatal characteristics differ. Methods: This was a retrospective study involving all pregnancies with polyhydramnios defined by a deepest pool of amniotic fluid ≥8 cm and a detailed ultrasound examination, a 75 g glucose tolerance test and a TORCH serology. Results: Between 2004 and 2010, 272 pregnancies fulfilled the inclusion criteria. In 89 (32.7%) and 65 (23.9%) cases, there was a fetal anomaly or diabetes. In 118 (43.4%) pregnancies, polyhydramnios was classified as idiopathic. In 11 (9.3%) of the 118 fetuses, an anomaly was found after birth, mainly gastrointestinal atresia. In these cases, median deepest pool of amniotic fluid was 9.6 cm, and median estimated fetal weight was at the 69th centile, whereas in cases without anomalies diagnosed after birth, median deepest pool was 9.0 cm and median estimated fetal weight at the 90th centile (Mann-Whitney U test: deepest pool p = 0.116, and estimated fetal weight centile p = 0.377). There was also no difference in the maternal and gestational age distribution of these cases (Mann-Whitney U test: maternal age p = 0.293, and gestational age p = 0.499). Conclusion: In about 40% of pregnancies, polyhydramnios remains unexplained during the course of pregnancy. In 10% of these cases, an anomaly will only be found after birth. In this group, antenatal characteristics such as amniotic fluid volume, estimated fetal weight or gestational and maternal age at the time of diagnosis do not help to detect these anomalies before birth.

Prenatal evaluation of the position of the fetal conus medullaris

To determine the position of the fetal conus medullaris during pregnancy in relation to the last vertebral body and to examine its use in detecting skin‐covered spinal dysraphism.

Prefrontal space ratio in second- and third-trimester screening for trisomy 21.

To evaluate the prefrontal space ratio (PFSR) in second‐ and third‐trimester euploid fetuses and fetuses with trisomy 21.

Comparison of three methods of cervical measurement in the first trimester: single-line, two-line, and tracing

To compare three methods of cervical length measurements using ultrasound in the first trimester: single‐line, two‐line, and tracing.

Prediction of Birth Weight Discordance in Twin Pregnancies by Second- and Third- Trimester Ultrasound

Introduction: Our purpose was to examine whether the prenatal prediction of a critical birth weight discordance (BWD) in twin pregnancies can be improved by using either different formulae for prenatal fetal weight estimation or single biometric measurements or by assessing the intertwin discordance in the second trimester rather than shortly before birth. Material and Methods: We conducted a retrospective study involving 196 twin pregnancies with an ultrasound examination between 18 and 25 weeks of gestation and one within 14 days prior to delivery. The accuracy was assessed by comparing the prenatal intertwin discordance (PID) with the BWD. PID was estimated by 5 common fetal weight estimation formulae and by single biometric measurements prior to delivery and in the second trimester. Results: The fetal weight estimation accuracy was similar in mono- and dichorionic pregnancies and the smaller and the larger twin. PID was most accurate with the fetal weight estimation formulae prior to delivery. The second-trimester measurements resulted in an underestimation of the BWD. Detection and false-positive rates for a BWD ≧20% were about 65 and 15%. Discussion: About two thirds of the twin pregnancies with a relevant BWD can be detected prior to delivery. An optimal detection rate requires fetal weight estimation close to delivery.

The frontal space measurement in euploid and aneuploid pregnancies at 11–13 weeks' gestation

The aim of this study is to evaluate whether the measurement of the frontal space (FS) improves first trimester combined aneuploidy screening.

Intraoperator and interoperator repeatability of manual and semi‐automated measurement of increased fetal nuchal translucency according to the operator's experience

To compare the intraoperator and interoperator repeatability of manual and semi‐automated measurement of increased nuchal translucency (NT) in sonographers with different levels of experience.

Optimal caliper placement: manual vs automated methods

To examine the inter‐ and intraoperator repeatability of manual placement of calipers in the assessment of basic fetal biometric measurements and to compare the results with those of an automated caliper placement system.

Screening auf Trisomie 18 und Trisomie 13 durch das kombinierte Anwenden der Risiko-Algorithmen für Trisomie 21, 18 und 13

PURPOSE Assessment of first-trimester combined screening for trisomy 18 and 13 with the combined use of the risk algorithms for trisomy 21, 18 and 13. MATERIALS AND METHODS First-trimester combined screening based on maternal and gestational age, fetal NT, PAPP-A and free β-hCG was assessed in 39 ,004 pregnancies. Patient-specific risks for trisomy 21, 18, 13 were computed based on the current FMF London algorithm. RESULTS The study population consisted of 38 ,751 singleton pregnancies including 39 cases with trisomy 18 or 13. In the aneuploid group, median delta NT was 0.72 mm, PAPP-A was 0.21 MoM and free β-hCG was 0.33 MoM. Although only 41 % of the NT measurements of fetuses with trisomy 18 or 13 were above the 95th percentile, the detection rates for trisomy 18 or 13 were 82 % with the trisomy 18/13 algorithm and 56.4 % with the trisomy 21 algorithm. The respective false-positive rates were 0.7 % and 4.7 %. The combination of the trisomy 18/13 and the trisomy 21 algorithm with the same cut-offs led to a detection rate of 94.9 % at an overall false-positive rate of 5.0 %. CONCLUSION Despite a substantial underestimation of the fetal NT, the combined use of the trisomy 18/13 and the trisomy 21 algorithm of the FMF London leads to a detection rate for trisomy 18/13 of about 95 % for a false-positive rate of 5.0 %.

OP23.03: First trimester combined screening with PLGF, free β-HCG and PAPP-A

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.