The absence of one umbilical artery (SUA) is the most common malformation of the umbilical cord. It may accompany other abnormalities or occur as an isolated defect. We examined 885 fetuses, terminated following the prenatal diagnosis of serious or lethal malformations between April 1977 and March 1989, for the presence of SUA. We found 62 cases of SUA. This represents an incidence of 7.01% (62/885). The most common abnormalities found in association with SUA were: (1) multiple malformations (8/11 cases, SUA incidence = 72.7%), (2) ADAM complex (7/14 cases, SUA incidence = 50.%), (3) multicystic renal dysplasia (5/20 cases, SUA incidence = 25.%), and (4) Potter sequence (5/21 cases, SUA incidence = 23.8%). These associations have not been documented previously. In 6 fetuses the Meckel syndrome was diagnosed, and SUA was present in 2 of these. Therefore, SUA may represent an additional anomaly in Meckel syndrome that has not been reported previously.

The aim of this study was to examine the prevalence of major and minor anomalies according to the increase of NT thickness. Methods: This is a long-term retrospective study in which singleton gestations of euploid fetuses with increased NT were analyzed. NT measurement was performed in the first trimester examination according to the criteria of fetal medicine foundation (FMF) when the fetal crown-rump length (CRL) was 45 to 84 mm. The cases were followed up from 1 to 5 years postpartum to assess the presence of CHD and to point out other anomalies that could be associated with increased NT. Results: The outcome of 133 cases could be analysed out of 198 pregnancies of which in 55 cases some congenital anomalies (minor or major) were revealed up to the 5 years of life (prevalence of 41.4%). The prevalence of CHDs, including the defects of the great vessels, stood out among the others. In the group with NT between 95th and 99th centiles four cases with minor heart problems were identified (11.1%, 4/36). The rate of major cardiac defects proved to be 13.3% (6/45) in the group with NT between 3.5-4.4 mm, and 17.3% (9/52) in the group with NT > 4.5 mm. Among the 35 healthy children with various minor health problems not related to the presence of increased nuchal translucency there were 7 cases with hydrocele. In 3 of them it was associated with unilateral inguinal hernia but in 3 it was isolated and one was part of a complex malformation (The rate of other organ-specific anomalies did not prove to be significant). In the whole study population only thirteen cases (9.8%) ended up in intrauterine death, or arteficial abortion. Conclusion: The prevalence of major cardiac defects as well as other major anomalies increases with fetal nuchal thickness. Since the prevalence of CHD is 100 times higher in the population of fetuses with NT above 4.5 mm, specialist fetal echocardiography should be offered in the second trimester together with other follow-up investigations. Among the children without any major abnormalities, a high number of minor anomalies were revealed during the long-term follow-up. These anomalies do not have significant disadvantage to the quality of life, but some of them necessitates short or long-term medical treatment and this should also be leveled with the future parents. Despite the numerous investigations the exact etiology of increased NT remains unknown. The relatively high prevalence of hydrocele in the newborns in our material raises the question wheather it is related to the presence of NT in the fetal period because of abnormal lymphatic development or alterations in the extracellular matrix. Further long-term follow-up studies could probably contribute to find explanation on the etiology of increased NT in the first trimester. These data can be used when counseling parents of euploid fetuses with increased fetal NT.

Objective: To evaluate the efficacy of intraplacental lacunae by transvaginal sonography in diagnosing the placenta accreta and increta and the prediction of clinical outcome. Methods: Forty-seven patients delivered in our hospital with history of cesarean section, diagnosis of placenta previa totalis by transvaginal sonography, and postpartum placental pathology were included in the study. Intraplacental lacunae were classified into 4 different grades from 0 to 3 by the degree (HJ Finberg, 1992). Placental pathology was done to all the patients delivered, and in case of hysterectomy, pathologic examination of removed uterus was also performed.Then they were compared with antepartum sonographic findings. Results: The lacunae was found in 8 cases with grade 1, 11 cases with grade 2, 5 cases with grade 3, and they were not showed in 23 cases. Sensitivity, specificity, positive predictive value, and negative predictive value of diagnosing placenta accreta above grade 1 lacunae were 79.2%, 87.0%, 86.4%, and 80%, respectively. When the pathologic diagnosis of placenta and removed uterus were placenta increta or percreta, all sonographic findings were above grade 2 lacunae. Sensitivity, specificity, positive predictive value, and negative predictive value of diagnosing placenta increta with lacunae above grade 2 were 93.8%, 100%, 100%, and 96.9%. Hysterectomy was performed to 17 cases, among them, 1 case showed grade 1 lacuna, 11 cases showed grade 2 lacunae, and 5 cases showed grade 3 lacunae. Without lacunae, no hysterectomy was done. Comparing the absence of lacunae or grade 1 lacunae, the relative risks of cesarean hysterectomy was 17 folds in the above grade 2 lacunae. Conclusions: Lacunar findings of transvaginal ultrasonography in patients with placenta previa totalis and history of cesarean section are very usefulness for diagnosis of placenta accreta and increta. These might be used as a valuable clinical prognostic marker. OC015Head engagement can be determined by translabial ultrasound and is predictive of normal vaginal delivery H. P. Dietz, V. Lanzarone Royal Prince Alfred Hospital, Sydney, AustraliaObjective: Engagement of the fetal head at term has long been used as a predictor of labour outcome. Surprisingly, no attempts seem to have been made to define engagement with modern imaging techniques. A recent pilot study suggested that head engagement can be determined by translabial ultrasound and is strongly associated with delivery mode. In this paper the authors tested parameters of head engagement for their predictive value. Methods: 202 nulliparous women in their first ongoing pregnancy were seen between 36 and 40 weeks' gestation in a prospective observational study. The assessment included an interview, abdominal palpation and (in a subset of 154 women) vaginal examination for a Bishop Score, as well as translabial ultrasound. Antenatal and delivery information was obtained from patient notes and the institutional obstetric database. Head engagement was determined in the midsagittal translabial plan...

Poster abstractsCNTD, and to provide further diagnostic and potentially prognostic parameters. Methods: Orthogonal T2-weighted MR sequences, acquired during clinically indicated MR examinations (1.5 Tesla) of fetuses without spinal dysraphism (n = 81; 17-39 GW), with ONTDs (n = 18; 21 examinations; 19-34 GW) and with CNTDs (n = 6; 9 examinations; 19-32 GW), were used to measure the clivus-occiput angle (α) and the maximum transverse diameter of the posterior fossa (DM PF ). For statistical camparison of foetuses with normal brain development with those foetuses with spinal dysraphisms fetuses were age and sex matched. Results: In fetuses without NTDs a significant positive correlation between gestational age and α (r = 0.952; P < 0.001) as well as DM PF (r = 0.601; P < 0.001) was found. No significant sex specific differences concerning α or DM PF were found. In fetuses without spinal dysraphisms α was significantly different from fetuses with ONTDs (P < 0.001) but not with CNTDs (P = 0.327) and α was also significantly different between fetuses with ONTDs and CNTDs (P = 0.029). DM PF of fetuses without spinal dysraphisms was significantly different from DM PF of fetuses with ONTDs or CNTDs (both P < 0.001). Between these fetuses with ONTDs and CNTDs no significant difference in DM PF was found (P = 0.618). Conclusions:The morphology and size of the posterior fossa and especially the clivus-occiput angle (α) depends on the absence or presence of an ONTD or CNTD. In contrast to a published ultrasound study α does not remain constant during pregnancy but in our study correlates positively with gestational age. The clivusocciput angle (α) more than the maximum transverse diameter of the fetal posterior fossa (DM PF ) may allow to differentiate between these conditions and may aid in the evaluation of the postnatal prognosis.

Poster abstracts Conclusions: About a third of severe non chromosomic fetal malformations diagnosed by ultrasound examination may be detected at the 11 + 0 to 13 + 6 week scan.