F. Giorgetta

Intrapartum transperineal ultrasound assessment of fetal head progression in active second stage of labor and mode of delivery

To compare longitudinal changes in angle of progression (AoP) and midline angle (MLA) during the active second stage of labor according to the mode of delivery.

Persistence of increased uterine artery resistance in the third trimester and pregnancy outcome

To evaluate whether the persistence of abnormal findings in the third trimester following increased uterine artery (UtA) resistance in the second trimester is related to adverse pregnancy outcome.

Significance of uteroplacental Doppler at midtrimester in patients with favourable obstetric history

Objective: To reassess the usefulness of midtrimester uterine Doppler in low-risk multiparous women. Methods: We prospectively recruited low-risk pregnant women at 20–22 weeks attending our clinic. Among those, women with a favourable obstetric history (group A) were distinguished from nulliparous (group B) and of each group we measured uterine artery Doppler (pulsatility index (PI)). We evaluated the accuracy of uterine artery Doppler in the prediction of preeclampsia and small for gestational age (SGA) neonates. Results: Between January 2009 and October 2010, 382 women were included in the study of which 147 in group A and 235 in group B. Overall, 26/382 (6.8%) women presented preeclampsia and SGA occurred in 59/382 (15.4%) cases. In our population, at a 10% false positive rate (FPR) uterine artery Doppler showed a detection rate (DR) of 19.2% for preeclampsia and of 37.3% for SGA, with a higher sensitivity for SGA neonates delivered ≤ vs. >34 weeks (87% vs. 29.4%). The univariable receiver operating characteristics (ROC) curve by uterine artery PI yielded a significant prediction only for SGA in nulliparous women (areas under the curve (AUC) of 0.70; 95% CI 0.60–0.79). Conclusions: Our data confirmed that midtrimester uterine artery Doppler is not an efficient strategy in anticipating the risk of pregnancy complications among low-risk multiparous women.

Horizontal stomach: a new sonographic clue to the antenatal diagnosis of right-sided congenital diaphragmatic hernia

We report on two cases of isolated right-sided congenital diaphragmatic hernia (CDH) in which the condition was first suspected due to ultrasound visualization of a horizontal orientation of the fetal stomach in the abdomen. In the first case, a 38-year-old woman, gravida 2 para 1, attended the ultrasound department of Valduce Hospital, Como at 13 weeks’ gestation for a first-trimester scan. Fetal nuchal translucency thickness and anatomy appeared normal; however, an abnormal horizontal orientation of the fetal stomach was noted (Figure 1). At 20 weeks’ gestation, a massive protrusion of the liver into the fetal chest was documented, leading to the diagnosis of isolated right-sided CDH. Moderate lung hypoplasia was demonstrated (observed to expected lungto-head ratio was 41%, according to the longest diameter method)1. Antenatal findings were confirmed after birth and neonatal death occurred soon after delivery. In the second case, a 32-year-old woman, gravida 2 para 1, was referred to Bologna University Hospital at 24 weeks’ gestation after amniocentesis revealed a mosaic karyotype (46,XY[8]/46,XX[3]/45,X[2]). On ultrasound, hypospadias was suspected and a horizontal orientation of the fetal stomach was also noted (Figure 2) in an otherwise normal male fetus. At the follow-up scan performed at 29 weeks, an upward displacement of the fetal liver was detected, leading to the diagnosis of right-sided CDH (Videoclip S1). Antenatal findings were confirmed after birth. Surgical correction was attempted, but the neonate died a few days after surgery. Right-sided CDH has a poor prognosis and a low prenatal detection rate2–4. The latter seems to be explained by a number of factors, including the similar sonographic appearance of the liver and lung, the lack of associated dextrocardia and, more importantly, the absence of intrathoracic herniation of the stomach, an important sonographic marker for left-sided CDH2,5. Contrary to the perinatal outcome of left-sided CDH, the lack of intrathoracic stomach and bowel herniation typically seen in right-sided CDH does not confer a better prognosis5. As observed in our two cases, the horizontal orientation of the stomach in the abdomen may represent an indirect sonographic sign that could raise the suspicion of this condition. In both cases, the horizontal stomach was detected prior to the right-sided CDH itself, and based on this finding a further reassessment of fetal anatomy was scheduled at a later stage in gestation, resulting in unambiguous detection of the hernia. Horizontal orientation of the stomach in the early stages of this Figure 1 Ultrasound images from Case 1 at 13 weeks’ gestation, showing: (a) horizontal orientation of the stomach and (b) chest cross-sectional view.

The use of intrapartum ultrasound to diagnose malpositions and cephalic malpresentations

&NA; Fetal malpositions and cephalic malpresentations are well‐recognized causes of failure to progress in labor. They frequently require operative delivery, and are associated with an increased probability of fetal and maternal complications. Traditional obstetrics emphasizes the role of digital examinations, but recent studies demonstrated that this approach is inaccurate and intrapartum ultrasound is far more precise. The objective of this review is to summarize the current body of literature and provide recommendations to identify malpositions and cephalic malpresentations with ultrasound. We propose a systematic approach consisting of a combination of transabdominal and transperineal scans and describe the findings that allow an accurate diagnosis of normal and abnormal position, flexion, and synclitism of the fetal head. The management of malpositions and cephalic malpresentation is currently a matter of debate, and individualized depending on the general clinical picture and expertise of the provider. Intrapartum sonography allows a precise diagnosis and therefore offers the best opportunity to design prospective studies with the aim of establishing evidence‐based treatment. The article is accompanied by a video that demonstrates the sonographic technique and findings.

Cardiotocographic findings in the second stage of labor among fetuses delivered with acidemia: a comparison of two classification systems

BACKGROUND The RCOG classification system of CTG trace is widely used for the analysis of the fetal heart rate during the first and second stage of labor. Other authors proposed specific classification systems for the second stage traces. OBJECTIVE To evaluate the accuracy of RCOG and Piquard cardiotocographic patterns classification systems in predicting fetal acidemia in the second stage of labor. STUDY DESIGN This was a nested retrospective case-control study including fetuses delivered with metabolic acidemia in the second stage of labor and a matched group of non-acidemic fetuses as controls. Cases and controls were selected from the electronic medical records of the University Hospital of Bologna between 2008 and 2013. The last 60min of the cardiotocograms recorded during the second stage of labor were independently classified by a senior consultant and a trainee according to RCOG and Piquard classifications. The inter-observer agreement and the accuracy of the two classifications in predicting fetal acidemia were evaluated. RESULTS In all, 82 acidemic fetuses and 164 controls were recruited in the study period. Regarding the CTG traces assessment, the inter-observer agreement was moderate for both the categorizations (RCOG κ=0.584). Unclassifiable CTG patterns were more frequent among acidemic fetuses vs controls either at RCOG and at Piquard evaluation (26.8% vs 7.9%, p<0.001). Both systems yielded a moderate and comparable ability to predict fetal acidemia (RCOG ROC AUC=0.731; 95% CI 0.660-0.795; Piquard ROC AUC=0.773; 95% CI 0.704-0.833. DeLong z-test=1.186, p=0.236). CONCLUSIONS RCOG and Piquard systems have a moderate accuracy in identifying acidemic fetuses during the second stage of labor. The occurrence of unclassifiable findings seems significantly more common among the acidemic fetuses.

OP18.07: Head progression in fetuses with persistent occiput posterior position at delivery: longitudinal assessment by 3D ultrasound in the second stage

Results: Of all 206 women, 9 had a cesarean for fetal distress and were excluded. The remaining 197 had a mean age of 28.6 (15–41). Most were nulliparas (n = 112; 56.9%). Mean gestational age was 40.8 (37–41). Major indications for labor induction were postdates pregnancy (n = 163; 82.7%), gestational diabetes (n = 29; 14.7%) and pre-eclampsia (n = 5; 2.6%). Cesarean section was performed in 31 cases (15.7%). Mean birthweight was 3485 g (2390–4650). ROC curves indicated that the best cut-off of cervical lenght for predicting Cesarean delivery was > 30 mm (sensitivity 68%, specificity 55%, positive predictive value (PV) 22%, negative PV 90%) and for Bishop score was < 5 (sensitivity 84%, specificity 48%, positive PV 23%, negative PV 94%). On univariate analysis nulliparity, cervical length > 30 mm and Bishop score < 5 were all significantly associated with Cesarean delivery (P values of 0.001; 0.023; 0.001 respectively). When patients were selected according to parity, there was found a significant association of Bishop score and cervical length with Cesarean delivery for nulliparas, but not for multiparas. Bishop score < 5 had 83% sensitivity, 39% specificity, 31% positive PV and 88% negative PV for Cesarean delivery (P = 0.027). Cervical length > 30 had 67% sensitivity, 58% specificity, 54% positive PV and 84% negative PV for Cesarean delivery (P = 0.034). Conclusions: Our results suggest that Bishop score and cervical length provide a significant contribution in the prediction of labor induction in postterm pregnancies.

OP18.03: The longitudinal changes of the angle of progression and the midline angle in the active second stage according to the mode of delivery

Objectives: Standard ultrasound biometry charts are derived from a European population. It is known that there is a difference in birthweight in babies born to mothers of different ethnic groups. The aim was to evaluate standard and novel ultrasound biometry measurements in normal pregnancy in different maternal ethnic groups. Methods: This was a longitudinal observational ultrasound study. Participants were healthy pregnant women whose primary ethnicity was European, Maori, Pacific Island or Asian Indian. Only pregnancies with normal outcomes were included (n = 74). Each participant was scanned at 4 weekly intervals from between 16 and 18 weeks to delivery. Ultrasound measurements were biparietal diameter, head circumference, humeral diaphyseal length, abdominal circumference and femur length. 3D ultrasound measurements were thigh circumference, partial thigh volume, arm circumference and partial arm volume. Neonatal measurements were birthweight, head circumference, crown-heel length and thigh circumference. Statistical analysis included multilevel linear mixed effects modelling, which accounts for correlation of longitudinal measurements. Results: Maternal characteristics were similar, except for weight (P = 0.03), between the ethnic groups. There were significant differences (P < 0.05) in the longitudinal growth of skeletal growth parameters – BPD, HC and HDL particularly with slower growth rate in the Indian fetuses compared to the referent NZE. Fetal soft tissue measurements showed different growth velocity compared to skeletal biometry from early third trimester. The differences were more marked in the heavier ethnic group (Pacific Island) (P < 0.001). Significant differences were seen in neonatal parameters. Conclusions: Appropriate ethnic characteristics should be included in customised biometry charts. Growth velocity of soft tissue may be useful to determine growth abnormalities, especially after 34 weeks. Soft tissue growth may help distinguish fetal growth restriction or SGA or if macrosomia is pathological in Pacific Island diabetics.

OP18.04: 3D ultrasound evaluation of progression angle, progression distance and midline angle changes in nulliparous women according to second stage length

(ITU) during the active second stage according to the mode of delivery. Methods: A 3DUS ITU volume was acquired in a series of nulliparous women at the beginning of the active second stage (T1) and every 20 minutes thereafter (T2, T3, etc.). Following delivery, all 3DUS volumes were analysed and both AoP and MLA were measured. Both parameters were then compared between women who underwent spontaneous vaginal delivery (SVD, Group A) and those who underwent operative delivery (Group B). ROC curves were subsequently constructed for both parameters at different scan intervals to estimate their accuracy to predict SVD. Results: Among 71 women included in the study, 58 women underwent SVD, 8 were delivered by vacuum extraction and 5 underwent cesarean delivery. When compared with group B, group A had a significantly wider AoP only at T1 (140.9 ± 20.2◦ vs. 122.9 ± 16.7◦, P = 0.01) and T2 (149.7 ± 20.7◦ vs. 126.9 ± 17.5◦, P = 0.006). The ROC curves revealed an AUC ± SE of 0.731 ± 0.077 at T1 and of 0.785 ± 0.080 at T2. On the other hand, MLA was narrower in Group A only at T3 (21.2 ± 11.7◦ vs. 40.8 ± 27.9◦, P = 0.043), T4 (18.2 ± 15.0◦ vs. 47.4 ± 29.6◦, P = 0.020) and T5 (18.25 ± 6.0◦ vs. 34.7 ± 4.2◦, P = 0.034). ROC curves yielded an AUC at T3 of 0.750 ± 0.044, at T4 of 0.880 ± 0.089 and T5 of 1.000 ± 0.000. On stepwise forward multiple logistic regressions both AoP and MLA were associated with the spontaneous vaginal delivery (OR (exponential beta) 1.047 and 0.983 respectively)). Conclusions: Ultrasonographic assessment of fetal head descent in the second stage may play a role in the prediction of the mode of delivery.

OP22.10: 3D ultrasound evaluation of changes in the angle of progression in nulliparous women undergoing spontaneous vaginal and operative delivery

Objectives: To evaluate the proportion of fetal head rotation from occiput posterior (OP) to occiput anterior (OA) during labour, and to study if OP before labour are associated with a higher risk of operative deliveries. Methods: Multicenter prospective observational study was performed in three sites (Brooklyn, NY; Haifa, Israel) and included 178 singleton uncomplicated term pregnancies with unengaged head. The determination of fetal head station and position was done by using the LaborPro system (Trig Medical Inc, Yoqneam, Israel), leveraged on position tracker and ultrasound imaging. The occiput posterior defined as cases and non-occiput posterior defined as controls. Results: Before engagement, 76 (43%) fetuses were in occiput posterior position (OP), but 67 (88%) of them rotated to occiput anterior (OA) during labour. Eleven (6%) fetuses were delivered in OP, and 9 of them were in OP before engagement (P < 0.001). 22.4% of cases in the OP group underwent Cesarean section compared to 12.7% of controls (P < 0.001). Conclusions: Fetal occiput posterior position determined before head engagement by the LaborPro system was a significant risk of Cesarean section and persistent OP position at labor.