ISUOG Practice Guidelines: intrapartum ultrasound.

PURPOSE AND SCOPE: The purpose of these Guidelines is to review the published techniques of ultrasound in labor and their practical applications, to summarize the level of evidence regarding the use of ultrasound in labor and to provide guidance to practitioners on when ultrasound in labor is clinically indicated and how the sonographic findings may affect labor management. We do not imply or suggest that ultrasound in labor is a necessary standard of care.

Cranial and cerebral signs in the diagnosis of spina bifida between 18 and 22 weeks of gestation: a German multicentre study.

OBJECTIVE: The aim of this article is to study secondary cranial signs in fetuses with spina bifida in a precisely defined screening period between 18 + 0 and 22 + 0 weeks of gestation. METHOD: On the basis of retrospective analysis of 627 fetuses with spina bifida, the value of indirect cranial and cerebral markers was assessed by well-trained ultrasonographers in 13 different prenatal centres in accordance with the ISUOG (International Society of Ultrasound in Obstetrics and Gynecology) guidelines on fetal neurosonography. RESULTS: Open spina bifida was diagnosed in 98.9% of cases whereas 1.1% was closed spina bifida. Associated chromosomal abnormalities were found in 6.2%. The banana and lemon signs were evident in 97.1% and 88.6% of cases. Obliteration of the cisterna magna was seen in 96.7%. Cerebellar diameter, head circumference and biparietal diameter were below the 5th percentile in chromosomally normal fetuses in 72.5%, 69.7% and 52%, respectively. The width of the posterior horn of the lateral ventricle was above the 95th percentile in 57.7%. The secondary cranial and cerebral signs were dependent on fetal chromosome status and width of the posterior horn. Biparietal diameter was also dependent on the chromosome status with statistical significance p = 0.0068. Pregnancy was terminated in 89.6% of cases. CONCLUSION: In standard measuring planes, lemon sign, banana sign and an inability to image the cistern magna are very reliable indirect ultrasound markers of spina bifida. © 2014 John Wiley & Sons, Ltd.

Semi-Automatic Identification of the Fetal Profile and Nasal Bone Measurement at the Time of the Routine Mid-Trimester Ultrasound Scan.

PURPOSE: This study was designed to compare nasal bone length (NBL) measurements using a manual multiplanar mode with those made using a newer semi-automatic technique (Volume NT™) acquired by an experienced operator as well as measurements done by two independent observers with different levels of ultrasound experience (conventional 2 D vs. Volume NT™). MATERIALS AND METHODS: Ultrasound examination was performed prospectively on 81 pregnant women with a singleton pregnancy at the time of their routine mid-trimester ultrasound scan. RESULTS: The correct mid-sagittal plane of the fetal profile was successfully obtained using the semi-automatic technique in 53 of 81 cases. CONCLUSION: NBL measurements using conventional two-dimensional techniques showed significantly higher inter-observer variability than the semi-automatic program. Our study shows the feasibility of using a semi-automatic technique, especially for less experienced operators. Measurements obtained with the semi-automatic technique produced much less variable results around a mean than those obtained with conventional two-dimensional ultrasound.

Relationship between fetal head station established using an open magnetic resonance imaging scanner and the angle of progression determined by transperineal ultrasound.

OBJECTIVE: We investigated the correlation between the angle of progression measured by transperineal ultrasound and fetal head station measured by open magnetic resonance imaging (MRI), the gold standard, in pregnant women at full term. METHODS: Thirty-one pregnant women at full term with a fetus in the occipitoanterior position were enrolled. First, the distance between the leading part of the skull and the interspinal plane was obtained using an open MRI system with the patient in a supine position. Immediately after MRI, the angle of progression was obtained by transperineal ultrasound without changing the woman's posture. RESULTS: There was a significant correlation between the angle of progression determined by transperineal sonography and the distance between the presenting fetal part and the level of the maternal ischial spines (y = - 0.51x + 60.8, r(2) = 0.38, P < 0.001). None of the fetal heads was engaged at the time of MRI and ultrasound examinations. CONCLUSIONS: The present study demonstrated a predictable relationship between the angle of progression obtained by transperineal ultrasound and the traditional scale used to quantify fetal head descent. Based on our results, station 0 would correspond to a 120° angle of progression. However, this correlation is based on statistical assumptions only and has to be proven in future studies.

Measurement of fetal head descent using the 'angle of progression' on transperineal ultrasound imaging is reliable regardless of fetal head station or ultrasound expertise.

OBJECTIVES: To assess whether ultrasound experience or fetal head station affects the reliability of measurement of fetal head descent using the angle of progression on intrapartum ultrasound images obtained by a single experienced operator, and to determine reliability of measurements when images were acquired by different operators with variable ultrasound experience. METHODS: One experienced obstetrician performed 44 transperineal ultrasound examinations of women at term and in prolonged second stage of labor with the fetus in the occipitoanterior position. Three midwives without ultrasound experience, three obstetricians with < 5 years' experience and three obstetricians with > 10 years' experience measured fetal head descent based on the angle of progression in the images obtained. The angle of progression was measured by two obstetricians in independent ultrasound examinations of 24 laboring women at term with the fetus in the cephalic position to allow assessment of the reliability of image acquisition. Intraclass correlation coefficients (ICCs) with 95% confidence interval (CI) were used to evaluate interobserver reliability and Bland-Altman analysis was used to assess interobserver agreement. RESULTS: In total, 444 measurements were performed and compared. Interobserver reliability with respect to offline image analysis was substantial (overall ICC, 0.72; 95% CI, 0.63-0.81). ICCs were 0.82 (95% CI, 0.70-0.89), 0.81 (95% CI, 0.71-0.88) and 0.61 (95% CI, 0.43-074) for observers with > 10 years', < 5 years' and no ultrasound experience, respectively. There were no significant differences between ICCs among observer groups according to ultrasound experience. Fetal head station did not affect reliability. Bland-Altman analysis indicated reasonable agreement between measurements obtained by two different operators with > 10 years' and < 5 years' ultrasound experience (bias, -1.09 degrees ; 95% limits of agreement, -8.76 to 6.58). The reliability of measurement of the angle of progression following separate image acquisition by two experienced operators was similar to the reliability of offline image analysis (ICC, 0.86; 95% CI, 0.70-0.93). CONCLUSIONS: Measurement of the angle of progression on transperineal ultrasound imaging is reliable regardless of fetal head station or the clinician's level of ultrasound experience.

Transperineal ultrasound imaging in prolonged second stage of labor with occipitoanterior presenting fetuses: how well does the 'angle of progression' predict the mode of delivery?

OBJECTIVES: To compare the angle of progression on transperineal ultrasound imaging between different modes of delivery in prolonged second stage of labor with occipitoanterior fetal position. METHODS: We prospectively evaluated 41 women at term (>or= 37 weeks) with failure to progress in the second stage of labor. Only cases with occipitoanterior fetal position were included in the final analysis. These cases were classified into three groups: Cesarean section for failure to progress, vacuum extraction for failure to progress, and spontaneous delivery following prolonged second stage of labor. Transperineal ultrasound examination was performed just before digital examination and subsequent delivery. The angle between a line placed through the midline of the pubic symphysis and a line running from the inferior apex of the symphysis tangentially to the fetal skull (the so-called 'angle of progression') was measured offline by an observer blinded to the mode of delivery. RESULTS: There were 26 cases with occipitoanterior fetal position (Cesarean section, n = 5; vacuum extraction, n = 16; spontaneous delivery, n = 5). Logistic regression analysis showed a strong relationship between the angle of progression and the need for Cesarean delivery (R(2) measure of fit = 55%, likelihood ratio chi-square P < 0.0001). When the angle of progression was 120 degrees , the fitted probability of either an easy and successful vacuum extraction or spontaneous vaginal delivery was 90%. CONCLUSIONS: This is the first report to document a strong relationship between an objective ultrasound marker (angle of progression) and the mode of delivery following prolonged second stage of labor with occipitoanterior fetal position. A predictive model using this parameter would allow better decision making regarding operative delivery for obstructed labor.

Electromagnetic instability in plasmas heated by a laser field.

Electromagnetic instability is investigated in homogeneous plasmas heated by a laser wave in the range α=v_{0}^{2}/v_{t}^{2}≤2, where v_{0} is the electron quiver velocity and v_{t} is the thermal velocity. The anisotropic electron distribution function that drives unstable quasistatic electromagnetic modes is calculated numerically with the Vlasov-Landau equation in the high ion charge number approximation. A dispersion relation of electromagnetic waves which accounts for further nonlinear terms on v_{0}^{2} from previous results is derived. In typical simulation with ion charge number Z=13, a temperature T=5keV, a density n=9.8×10^{20}cm^{-3}, and a laser wavelength λ_{laser}=1.06µm, growth rates larger than 10^{12}s^{-1} in the quasicollisionless wave-number range were found for α≥1. In the same physical conditions and in the mildly collisional range a growth rate about 10^{11}s^{-1} was also obtained. The extent of the growth wave-number region increases significantly with increasing α.

Generalized linear transport theory in dilute neutral gases and dispersion relation of sound waves.

The transport processes in dilute neutral gases are studied by using the kinetic equation with a collision relaxation model that meets all conservation requirements. The kinetic equation is solved keeping the whole anisotropic part of the distribution function with the use of the continued fractions. The conservative laws of the collision operator are taken into account with the projection operator techniques. The generalized heat flux and stress tensor are calculated in the linear approximation, as functions of the lower moments, i.e., the density, the flow velocity and the temperature. The results obtained are valid for arbitrary collision frequency nu with the respect to kv(t) and the characteristic frequency omega, where k(-1) is the characteristic length scale of the system and v(t) is the thermal velocity. The transport coefficients constitute accurate closure relations for the generalized hydrodynamic equations. An application to the dispersion and the attenuation of sound waves in the whole collisionality regime is presented. The results obtained are in very good agreement with the experimental data.

Anisotropic electron-distribution function in inverse-bremsstrahlung-heated plasmas.

The electron-distribution function in homogeneous plasmas heated by a high-frequency laser field is calculated in velocity space from the Vlasov-Landau equation. The kinetic model is valid for moderate laser intensity defined by the relevant parameter α=v_{0}^{2}/v_{t}^{2}<0.5 where v_{0} and v_{t} are the peak velocity of oscillation in the high-frequency electric field and the thermal velocity, respectively. The results obtained constitute an improvement of the results reported in the literature devoted to weak electric field intensities. The electron-distribution function is calculated solving the kinetic equation with the use of the Legendre polynomial expansion within the laser field dipole approximation. It results in an infinite set of equations for the isotropic component f_{0}(v) and the anisotropic components f_{n≥1}(v) that we have solved numerically with appropriate truncation. For the second anisotropy f_{2}(v), we found that its maximum increases from the weak electric field intensity (α<0.01) to a moderate one (α=0.5) by a factor f_{2max}(α=0.5)/f_{2max}(α=0.01)≈48. Applications to the radiation pressure, electromagnetic instabilities, and photoabsorption are also considered.

Factors for Preterm Births in Germany - An Analysis of Representative German Data (KiGGS).

Introduction: Preterm birth is a global scourge, the leading cause of perinatal mortality and morbidity. This study set out to identify the principal risk factors for preterm birth, based on the German Health Interview and Examination Survey for Children and Adolescents (KiGGS). A range of possible factors influencing preterm birth were selected for inclusion in the questionnaire, covering factors such as gender, national origin, immigrant background, demography, living standard, family structure, parental education and vocational training. Methods: All data were taken from the aforementioned KiGGS survey conducted between 2003 and 2006. A total of 17 641 children and adolescents (8656 girls and 8985 boys) drawn from 167 German towns and municipalities deemed to be representative of the Federal Republic of Germany were included in the study. Gestational age at birth was available for 14 234 datasets. The questionnaire included questions from the following areas as possible factors influencing preterm birth: gender, national origins, immigrant background, demography, living standard, family structure, parental education and vocational training. Results: The preterm birth rate was 11.6 %, higher than that of other national statistical evaluations. Around 57.4 % of multiple pregnancies and 10 % of singleton pregnancies resulted in preterm delivery. Multiple pregnancy was found to be the most important risk factor (OR 13.116). With regard to national origins and immigration background, mothers from Turkey, the Middle East, and North Africa had a higher incidence of preterm birth. Preterm birth was more prevalent in cities and large towns than in small towns and villages. Conclusion: Risk factors associated with preterm birth were identified. These should help with the early identification of pregnant women at risk. The preterm birth rate in our survey was higher than that found in other national statistical evaluations based on process data. More than half of all multiple pregnancies ended in preterm birth.

Right-sided pulmonary aplasia: longitudinal lung function studies in two cases and comparison to results from term healthy neonates.

Agenesis of the right lung was diagnosed prenatally in two neonates born at 36 and 37 weeks, respectively. Computed tomographic scans and magnetic resonance imaging indicated that both cases had a Type 2 pulmonary agenesis, which was confirmed later by bronchoscopy. Both patients were clinically stable during the neonatal period. Serial pulmonary function tests revealed a decrease in specific respiratory system compliance (sCrs) in both neonates and a marked discrepancy between functional residual capacity measured by the nitrogen washout technique (FRCN2) and by plethysmography (FRCpleth) on follow-up. Early decrease of respiratory system compliance (Crs) and increase of respiratory system resistance (Rrs) in one infant preceded the onset of tracheal stenosis, which remained asymptomatic until the age of 8 weeks, when the infant developed acute respiratory failure requiring intubation and mechanical ventilation with high airway pressures. Aortopexy, implantation of a tissue expander into the right hemithorax, and laser ablation of fibrotic tissue at the site of tracheal stenosis were performed to achieve successful extubation. The second infant remained asymptomatic. Values for lung mechanics and volumes for both infants with pulmonary aplasia were as follows: Crs, 3.43 and 10.60 mL x kP(-1) x kg(-1); sCrs, 0.23 and 1.28 kpa(-1); Rrs, 11.1 and 7.4 kpa x s x L(-1); FRCN2, 14.9 and 10.2 mL x kg(-1); FRCpleth, 28.2 and 25.8 mL x kg(-1); FRCN2: FRCpleth ratio, 0.56 and 0.54 for patients 1 and 2, respectively. These values differed considerably from results of a control group of nine term healthy neonates (Crs, 10.0+/-1.8 mL x kPa(-1) x kg(-1); sCrs, 0.43+/-0.08 kpa(-1); Rrs, 5.10+/-0.55 kpa x s x L(-1); FRCN2, 24.0+/-2.5 mL x kg(-1); FRCpleth, 31.1+/-6.0 mL x kg(-1); FRCN2:FRCpleth ratio, 0.78+/-0.10). In conclusion, serial assessment of lung mechanics and pulmonary gas volumes detects airway obstruction early in neonates with unilateral lung agenesis. Bronchoscopy is recommended. Along with conventional surgical procedures, an expandable implant may improve management or prevent respiratory failure in selected cases.

Conversion of umbilical arterial Doppler waveforms to cardiac cycle triggering signals: a preparatory study for online motion-gated three-dimensional fetal echocardiography.

To remove motion artefacts, a device was built to convert "noisy" umbilical arterial Doppler waveforms (UADWs) from an ultrasound (US) system into sharp ECG R-wave-like cardiac cycle triggering signals (CCTSs). These CCTSs were then used to gate a simultaneous (online) 3-D acquisition of sectional fetal echocardiograms from another US system. To test the conversion performance, a study was carried out in sheep fetal twins. Pulmonary arterial flow waveforms (PAFWs) from implanted probes were traced, in the meantime, to determine the reference cardiac cycle. Interference caused by running the two nonsynchronised US systems was controlled to three degrees (not-noticeable, moderate, and severe), together with high (> or = 40 cm/s) and low (< 40) flow velocities on UADWs. The conversion efficiency, assessed by the percentage of UADWs converted into CCTSs, was in the range of 83% to 100% for not-noticeable and moderate interference, and 0% to 71% for severe interference. The triggering accuracy, assessed by [(time lag mean between the onsets of PAFWs and corresponding CCTSs) -- (its 99% confidence level)] / the mean, was 90% to 96% for the not-noticeable interference high- and low-flow groups and for the moderate interference high-flow group; 19% to 93% for the moderate interference low-flow group; and from not obtainable up to 90% for the severe interference groups. The results show that UADWs can be used as a satisfactory online motion-gating source even in the presence of moderate interference. The major problems are from severe interference or moderate interference with low-flow velocity, which can be minimised/eliminated by the integration of the individual systems involved.

Pulmonary arterial Doppler velocimetry in fetuses with lung hypoplasia.

OBJECTIVE: The aim of the study was to examine Doppler flow velocity waveforms in the main stems of the pulmonary arteries in fetuses with autopsy-proven lung hypoplasia and to find out whether in these conditions typical patterns can be found. STUDY DESIGN: Doppler spectra were derived from the main stem of the right or left pulmonary artery in fetuses at high-risk for lung-hypoplasia. The following Doppler parameters were analyzed and compared to reference ranges: peak systolic velocity, acceleration time, time velocity integral, end-systolic reverse flow, pulsatility index (PI). Pulmonary hypoplasia was found in nine cases at autopsy after termination of pregnancy (19-23 weeks). According to etiology, three groups were considered: (A) bilateral renal malformations (n=4), (B) congenital diaphragmatic hernia (n=2), and (C) miscellaneous malformations including heart defects (n=3). RESULTS: The following Doppler parameters were found: normal values in end-systolic reversal flow in all cases, decreased peak systolic velocity and acceleration time in 3/9, decreased time velocity integral in 4/9 and increased pulsatility index in 6/9. Considering the etiology of pulmonary hypoplasia the pulsatility index was found to be the most sensitive, since all fetuses in groups A and B had an abnormal PI. CONCLUSIONS: Human fetuses with renal malformations and diaphragmatic hernia associated with lung hypoplasia show as early as 19-23 weeks of gestation an abnormal Doppler spectrum in the main stems of the pulmonary arteries. Increased PI is the best parameter to detect flow abnormality in this condition. Since the Doppler spectrum depends on cardiac anatomy and function, PI in lung hypoplasia seems to be reliable only when cardiac defects are absent.

Soluble adhesion molecule profile in normal pregnancy and pre-eclampsia.

OBJECTIVE: An exaggerated inflammatory response has been implicated as the cause of endothelial cell dysfunction and the maternal syndrome of pre-eclampsia. Adhesion molecules play a central role in the adherence of leukocytes to endothelial cells and the subsequent migration of white blood cells into perivascular tissue. Cellular forms of adhesion molecules mediate specific steps of leukocyte-endothelial cell interaction, and have been implicated in the pathophysiology of preeclampsia. Soluble forms of these molecules can be detected in plasma, and their concentrations are thought to reflect the degree of activation of a particular cell type. Elevations in soluble P-selectin (sP-selectin) reflect platelet activation; changes in soluble L-selectin (sL-selectin) suggest leukocyte activation; and an increase in soluble forms of E-selectin (sE-selectin), vascular cell adhesion molecule 1 (sVCAM-1), intercellular adhesion molecule 1 (sICAM-1) and platelet endothelial cell adhesion molecule (sPECAM-1) indicate endothelial cell activation/dysfunction. The objective of this study was to determine whether normal pregnancy and pre-eclampsia were associated with changes in the concentrations of soluble selectins and members of the immunoglobulin superfamily of adhesion molecules. STUDY DESIGN: A cross-sectional study was conducted to determine the plasma concentrations of sL-selectin, sE-selectin, sP-selectin, sVCAM-1, sICAM-1 and sPECAM-1 in peripheral blood obtained from non-pregnant women (n = 20), normal pregnant women (n = 100) and patients with pre-eclampsia (n = 55). Concentrations of soluble adhesion molecules were determined with enzyme-linked immunoassays. Parametric statistics were used for data analysis. RESULTS: Normal pregnancy was associated with a significant increase in the maternal plasma concentration of sP-selectin, a decrease in sL-selectin, and no change in sE-selectin, sVCAM-1, sICAM-1 and sPECAM-1. In contrast, pre-eclampsia was associated with a significant increase in sP-selectin, sE-selectin and sVCAM-1, a decrease in sL-selectin, but no change in sICAM-1 and sPECAM-1 concentrations. CONCLUSIONS: The increased concentration of sP-selectin and decreased sL-selectin, as well as the lack of change in endothelial cell-associated soluble adhesion molecules suggest that pregnancy is associated with platelet and leukocyte activation, but not endothelial cell activation. In contrast, pre-eclampsia appears to be characterized by activation of platelets, leukocytes and endothelial cells.

Elevated monocyte chemotactic protein-1 in amniotic fluid is a risk factor for pregnancy loss.

OBJECTIVE: Pregnancy loss after mid-trimester amniocentesis occurs in 0.5-1% of cases and is frequently attributed to the procedure. Accumulating evidence implicates a pre-existing, but clinically silent, intra-amniotic inflammation in the etiology of adverse pregnancy outcome after mid-trimester amniocentesis. Monocyte chemotactic protein-1 (MCP-1) is a potent chemokine produced by a wide variety of cells during the course of an inflammatory response. This study was designed to assess if the amniotic fluid concentration of this chemokine identifies patients at risk for spontaneous abortion and/or fetal death. METHOD: A retrospective case-control study of women who had a mid-trimester amniocentesis was designed. Cases (n = 10) consisted of patients who had a spontaneous pregnancy loss after the procedure, while the control group (n = 84) consisted of patients who had a normal pregnancy outcome after mid-trimester amniocentesis. MCP-1 was measured by a specific enzyme immunoassay (sensitivity, 18.3 pg/ml). The Kolmogorov-Smirnov test was utilized to assess normal distribution of the data. Logarithmic transformation was applied to achieve normality. Statistical analysis was performed using Student's t test. A receiver operating characteristic (ROC) curve analysis was used to select a cut-off to dichotomize amniotic fluid concentrations of MCP-1. RESULTS: MCP-1 was detectable in all amniotic fluid samples. Patients who had a mid-trimester amniocentesis and a subsequent pregnancy loss had a higher mean amniotic fluid log MCP-1 concentration than those with a normal pregnancy outcome (pregnancy loss, mean 2.95 +/- 0.19 pg/ml vs. normal outcome, mean 2.78 +/- 0.19 pg/ml; p = 0.01). A cut-off of > 765 pg/ml was selected by ROC curve analysis (area under the curve, 0.74; p = 0.01). An amniotic fluid concentration of MCP-1 above this level was strongly associated with pregnancy loss (odds ratio, 7.35; 95% confidence interval, 1.7-31.1), a sensitivity of 70%, and a specificity of 76%. CONCLUSION: A subset of women who had a pregnancy loss after a mid-trimester amniocentesis had higher concentrations of the chemokine MCP-1 than those who had a normal pregnancy outcome. Subclinical intra-amniotic inflammation is a risk factor for pregnancy loss after mid-trimester amniocentesis. This observation may have medicolegal and clinical implications. An elevated MCP-1 concentration in amniotic fluid of patients with a pregnancy loss after a mid-trimester amniocentesis indicates that a pathological condition was present at the time of the procedure.

Subclinical myocardial injury in small-for-gestational-age neonates.

OBJECTIVE: Small-for-gestational-age (SGA) infants are at risk for premature death from cardiovascular disease (myocardial infarction and stroke), hypertension, and diabetes in adult life. Severe intrauterine growth restriction is often associated with subclinical cardiovascular abnormalities detectable during fetal echocardiography. The objective of this study was to determine whether SGA newborns have evidence of myocardial injury at birth. STUDY DESIGN: Cardiac troponin I, a specific marker of myocardial injury widely used for the diagnosis of myocardial infarction in adults, was determined in umbilical cord blood. Umbilical cord venous blood was obtained at the time of birth from 72 SGA newborns (birth weight below the 10th centile for gestational age) and 309 newborns whose birth weights were appropriate for gestational age (AGA). Cardiac troponin I was determined with a commercially available immunoassay (sensitivity 0.2 ng/ml) employed in clinical laboratories (Immulite 2000, Diagnostic Products Corp., Los Angeles, CA). RESULTS: Cardiac troponin I was not detectable in any of the blood samples from AGA infants. In contrast, 4.2% (3/72) of SGA infants had detectable cardiac troponin I in umbilical cord blood (Fisher's exact test, p = 0.007). CONCLUSION: A subgroup of SGA newborns undergoes myocardial injury before birth. This insult may predispose to the development of adult premature cardiovascular disease and death.

Impact of intrapartal ultrasound to assess fetal head position and station on the type of obstetrical interventions at full cervical dilatation.

OBJECTIVES: Recent ultrasound studies have shown that it is feasible to objectively and reproducibly assess fetal head position and station within the pelvis. We sought to evaluate the impact of this new approach on decision making by physicians in a cohort of women with a prolonged second stage of labor. METHODS: This was a retrospective cohort study that included all women with fetuses in cephalic presentation, who were diagnosed with a prolonged second stage of labor, and who delivered in a 1-year period. We compared a group of women (n = 121) with a prolonged second stage of labor who underwent intrapartal ultrasound prior to obstetrical intervention (Group A, n = 43) with a group of women for whom the delivery modus was decided upon after clinical digital examination alone (Group B, n = 78). RESULTS: There were no significant differences in maternal and neonatal morbidity between both groups. The rate of second-stage cesarean section was significantly higher (p < 0.50) in Group B without ultrasound compared to Group A with ultrasound prior to operative delivery (20/78 vs. 7/43). Seven patients in Group A delivered spontaneously, but none of the patients in Group B had spontaneous deliveries. CONCLUSIONS: Intrapartal ultrasound in patients with a prolonged second stage of labor may change obstetrical practice by reducing the number of second stage cesarean section without increasing maternal and neonatal morbidity.