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Background Improved information about the evolution of fetal head rotation during labor is required. Ultrasound methods have the potential to provide reliable new knowledge about fetal head position. Objective The aim of the study was to describe fetal head rotation in women in spontaneous labor at term using ultrasound longitudinally throughout the active phase. Study Design This was a single center, prospective cohort study at Landspitali - The National University Hospital of Iceland, Reykjavik, Iceland, from January 2016 to April 2018. Nulliparous women with a single fetus in cephalic presentation and spontaneous labor onset at ≥37 weeks’ gestation were eligible. Inclusion occurred when the active phase could be clinically established by labor ward staff. Cervical dilatation was clinically examined. Fetal head position and subsequent rotation were determined using both transabdominal and transperineal ultrasound. Occiput positions were marked on a clockface graph with 24 half-hour divisions and categorized into occiput anterior (≥10- and ≤2-o’clock positions), left occiput transverse (>2- and 8- and Results We followed the fetal head rotation relative to the initial position in the pelvis in 99 women, of whom 75 delivered spontaneously, 16 with instrumental assistance, and 8 needed cesarean delivery. At inclusion, the cervix was dilated 4 cm in 26 women, 5 cm in 30 women, and ≥6 cm in 43 women. Furthermore, 4 women were examined once, 93 women twice, 60 women 3 times, 47 women 4 times, 20 women 5 times, 15 women 6 times, and 3 women 8 times. Occiput posterior was the most frequent position at the first examination (52 of 99), but of those classified as posterior, most were at 4- or 8-o’clock position. Occiput posterior positions persisted in >50% of cases throughout the first stage of labor but were anterior in 53 of 80 women (66%) examined by and after full dilatation. The occiput position was anterior in 75% of cases at a head-perineum distance of ≤30 mm and in 73% of cases at an angle of progression of ≥125° (corresponding to a clinical station of +1). All initial occiput anterior (19), 77% of occiput posterior (40 of 52), and 93% of occiput transverse positions (26 of 28) were thereafter delivered in an occiput anterior position. In 6 cases, the fetal head had rotated over the 6-o’clock position from an occiput posterior or transverse position, resulting in a rotation of >180°. In addition, 6 of the 8 women ending with cesarean delivery had the fetus in occiput posterior position throughout the active phase of labor. Conclusion We investigated the rotation of the fetal head in the active phase of labor in nulliparous women in spontaneous labor at term, using ultrasound to provide accurate and objective results. The occiput posterior position was the most common fetal position throughout the active phase of the first stage of labor. Occiput anterior only became the most frequent position at full dilatation and after the head had descended below the midpelvic plane.

Objective: To explore the duration of the active phase of the second stage of labour in relation to maternal pre-pregnant body mass index (BMI). Design: Retrospective cohort study. Setting: Labour wards of three Norwegian university hospitals, 2012–2019. Population: Nulliparous and parous women without previous caesarean section with a live singleton fetus in cephalic presentation and spontaneous onset of labour, corresponding to the Ten Group Classification System (TGCS) group 1 and 3. Methods: Women were stratified to BMI groups according to WHO classification, and estimated median duration of the active phase of the second stage of labour was calculated using survival analyses. Caesarean sections and operative vaginal deliveries during the active phase were censored. Main outcome measures: Estimated median duration of the active phase of second stage of labour. Results: In all, 47 942 women were included in the survival analyses. Increasing BMI was associated with shorter estimated median duration of the active second stage in both TGCS groups. In TGCS group 1, the estimated median durations (interquartile range) were 44 (26–75), 43 (25–71), 39 (22–70), 33 (18–63), 34 (19–54) and 29 (16–56) minutes in BMI groups 1–6, respectively. In TGCS group 3, the corresponding values were 11 (6–19), 10 (6–17), 10 (6–16), 9 (5–15), 8 (5–13) and 7 (4–11) minutes. Increasing BMI remained associated with shorter estimated median duration in analyses stratified by oxytocin augmentation and epidural analgesia. Conclusion: Increasing BMI was associated with shorter estimated median duration of the active second stage of labour. publishedVersion

To evaluate the accuracy and reliability of a new ultrasound technique for the automatic assessment of the head-perineum distance (HPD) during childbirth.HPD was measured on a total of 40 acquisition sessions in 30 laboring women both automatically by an innovative algorithm and manually by trained sonographers, assumed as gold standard.A significant correlation was found between manual and automatic measurements (Intra-CC = 0.994). High values of the coefficient of determination (The automatic algorithm for the assessment of the HPD represents a reliable technique.

Oxytocin augmentation is essential in labor management, but how to optimize its use is still debated. Joint international guidelines regarding prolonged labor and the use of oxytocin augmentation are still not available. Due to its potential harmful side effects, a decreased use of oxytocin is encouraged. We aimed to implement a structured protocol on the use of oxytocin augmentation and to observe changes in labor outcomes.The protocol was implemented at the Obstetric Department of Sørlandet Hospital, Kristiansand, Norway on 1 January 2012; therefore, data from the hospital were collected prospectively and compared for two time-period cohorts: the historic control cohort (2009-2010) and the study period cohort (2012-2013). The structured protocol instructs, and restricts, the birth attendants to diagnose prolonged labor, by protocol definition only, before commencing oxytocin infusion for augmentation. Nulliparous women with singleton, term deliveries (≥37 weeks), cephalic presentation, and spontaneous onset of labor (Ten-Group Classification System (TGCS) group 1) were included in the analysis. The main outcome was use of oxytocin augmentation.The study cohort and control cohort comprised 1103 (26.2%) and 1399 (33.1%) of all laboring women, respectively (Implementation of a protocol of structured use of oxytocin augmentation reduced the frequency, dosage, and duration of oxytocin without increasing the cesarean section rate in TGCS group 1.

We hypothesised that the examinations offered to pregnant women at fetal medicine centres differ from those offered to other pregnant women in Norway. We therefore wanted to investigate the incidence, prenatal diagnostics and pregnancy terminations in cases of trisomy 21. We also wanted to compare the figures from the National Center for Fetal Medicine, St Olav's Hospital, Trondheim University Hospital, with national figures for Norway.We analysed figures for the period 1999-2018 retrospectively. National data were compared with an unselected population whose local hospital is St Olav's Hospital. National figures were retrieved from the Medical Birth Registry of Norway and local figures were from the quality registry at the National Center for Fetal Medicine.The national incidence of trisomy 21 was 0.20 %, varying from 0.14 % to 0.23 %, and showed a significant increase over time (p0.01). The increasing incidence showed an association with increasing age in the women (p0.01). The incidence of live births was stable, even though the proportion of pregnancy terminations increased. In the local population, the incidence of trisomy 21 was 0.19 %. A total of 68.2 % of the local population were diagnosed prenatally, and 87.7 % of these pregnant women terminated the pregnancy. There was a significantly higher proportion of pregnancy terminations in the local population than in the remainder of the national population (p0.01).The difference in the proportion of pregnancy terminations may be associated with variation in access to prenatal diagnostics.

The first stage of labor is from the start of active labor until the cervix is fully dilatated. To assess labor progress during this stage, a clinical examination has traditionally been done. The cervical dilatation, fetal head position, and fetal head station are evaluated. Moreover, these observations can be made with an ultrasound examination. Studies have shown that traditional clinical examinations are subjective, have poor reproducibility, and are unreliable. Ultrasound examinations of the fetal head station and fetal head position in the first stage of labor might predict labor outcome and mode of delivery and can help in decision making when prolonged first stage of labor is diagnosed.

The mechanics of labor describe the forces required for fetal descent, and the movements that the fetus must perform to overcome the resistance met by the maternal bony pelvis and soft tissue. The fetus negotiates the birth canal and rotational movements are necessary for descent. Anglo-American literature lists 7 cardinal movements, namely engagement, descent, flexion, internal rotation, extension, external rotation, and expulsion. German and older English literature lists only 4 rotational movements as the cardinal movements and excludes engagement, descent, and expulsion. We would argue that descent is the main purpose of the uterine powers and cardinal movements, a description of the rotational movements the fetal head and shoulders must perform to obtain descent. Ultrasound offers a historically unique opportunity for noninvasive, dynamic studies of the mechanics of labor. The information gathered by clinical examination and ultrasound should be integrated into clinical decision making.

Background Determining fetal head descent, expressed as fetal head station and engagement is an essential part of monitoring progression in labor. Assessing fetal head station is based on the distal part of the fetal skull, whereas assessing engagement is based on the proximal part. Prerequisites for assisted vaginal birth are that the fetal head should be engaged and its lowermost part at or below the level of the ischial spines. The part of the fetal head above the pelvic inlet reflects the true descent of the largest diameter of the skull. In molded (reshaped) fetal heads, the leading bony part of the skull may be below the ischial spines while the largest diameter of the fetal skull still remains above the pelvic inlet. An attempt at assisted vaginal birth in such a situation would be associated with risks. Therefore, the vaginal or transperineal assessments of station should be supplemented with a transabdominal examination. We suggest a method for the assessment of fetal head descent with transabdominal ultrasound. Objective To investigate the correlation between transabdominal and transperineal assessment of fetal head descent, and to study fetal head shape at different labor stages and head positions. Study Design Women with term singleton cephalic pregnancies admitted to the labor ward for induction of labor or in spontaneous labor, at the Cairo University Hospital and Oslo University Hospital from December 2019 to December 2020 were included. Fetal head descent was assessed with transabdominal ultrasound as the suprapubic descent angle between a longitudinal line through the symphysis pubis and a line from the upper part of the symphysis pubis extending tangentially to the fetal skull. We compared measurements with transperineally assessed angle of progression and investigated interobserver agreement. We also measured the part of fetal head above and below the symphysis pubis at different labor stages. Results The study population comprised 123 women, of whom 19 (15%) were examined before induction of labor, 8 (7%) in the latent phase, 52 (42%) in the active first stage and 44 (36%) in the second stage. The suprapubic descent angle and the angle of progression could be measured in all cases. The correlation between the transabdominal and transperineal measurements was −0.90 (95% confidence interval, −0.86 to −0.93). Interobserver agreement was examined in 30 women and the intraclass correlation coefficient was 0.98 (95% confidence interval, 0.95–0.99). The limits of agreement were from −9.5 to 7.8 degrees. The fetal head was more elongated in occiput posterior position than in non-occiput posterior positions in the second stage of labor. Conclusion We present a novel method of examining fetal head descent by assessing the proximal part of the fetal skull with transabdominal ultrasound. The correlation with transperineal ultrasound measurements was strong, especially early in labor. The fetal head was elongated in the occiput posterior position during the second stage of labor.

Introduction There is limited evidence on the safety and outcome of induction of breech labor. In this study, we aimed to compare the outcomes of spontaneous and induced breech deliveries and to describe variations in induction rates. Material and methods This was a retrospective cohort study comprising 1054 singleton live fetuses in breech presentation at Trondheim University Hospital from 2012 to 2019. The main outcome was intrapartum cesarean section, and secondary outcomes were postpartum hemorrhage, anal sphincter ruptures, Apgar scores, pH in the umbilical artery, and metabolic acidosis. All data were obtained from the hospital birth journal. Results Induction of labor was performed in 127/606 (21.0%) women with planned vaginal birth. The frequency of intrapartum cesarean section was 48.0% for induced labor vs 45.7% for spontaneous labor (P = .64). We found no differences in the frequency of postpartum hemorrhage or anal sphincter ruptures between induced and spontaneous births. The median pH in the umbilical artery was significantly lower in neonates with induced labor compared with neonates with spontaneous labor (7.22 vs 7.25; P = .02). The frequency of pH

Fetal head descent can be expressed as fetal station and engagement. Station is traditionally based on clinical vaginal examination of the distal part of the fetal skull and related to the level of the ischial spines. Engagement is based on a transabdominal examination of the proximal part of the fetal head above the pelvic inlet. Clinical examinations are subjective, and objective measurements of descent are warranted. Ultrasound is a feasible diagnostic tool in labor, and fetal lie, station, position, presentation, and attitude can be examined. This review presents an overview of fetal descent examined with ultrasound. Ultrasound was first introduced for examining fetal descent in 1977. The distance from the sacral tip to the fetal skull was measured with A-mode ultrasound, but more convenient transperineal methods have since been published. Of those, progression distance, angle of progression, and head-symphysis distance are examined in the sagittal plane, using the inferior part of the symphysis pubis as reference point. Head-perineum distance is measured in the frontal plane (transverse transperineal scan) as the shortest distance from perineum to the fetal skull, representing the remaining part of the birth canal for the fetus to pass. At high stations, the fetal head is directed downward, followed with a horizontal and then an upward direction when the fetus descends in the birth canal and deflexes the head. Head descent may be assessed transabdominally with ultrasound and measured as the suprapubic descent angle. Many observational studies have shown that fetal descent assessed with ultrasound can predict labor outcome before induction of labor, as an admission test, and during the first and second stage of labor. Labor progress can also be examined longitudinally. The International Society of Ultrasound in Obstetrics and Gynecology recommends using ultrasound in women with prolonged or arrested first or second stage of labor, when malpositions or malpresentations are suspected, and before an operative vaginal delivery. One single ultrasound parameter cannot tell for sure whether an instrumental delivery is going to be successful. Information about station and position is a prerequisite, but head direction, presentation, and attitude also should be considered.

The cesarean section rates are rising and much higher than medical indicated [1]. Cesarean section is associated with risks of uterine rupture, abnormal placentation, ectopic pregnancy, stillbirth, and preterm birth in subsequent pregnancies [2]. Avoiding the first cesarean influences delivery mode in subsequent deliveries. WHO recommends that every effort should be made to provide cesarean sections to women in need, rather than striving to achieve a specific rate. The risk for complications is highest when performed at low stations, and a vacuum extraction may be a safe alternative. Levine et al. has shown a sixfold increase in preterm birth in subsequent deliveries following a second-stage cesarean section [3]. In many countries there is an underuse of operative vaginal deliveries [4]. More use of vacuum extractions has the potential to reduce the rate of cesarean sections, and both pediatric and maternal benefits may be achieved.

Background To accommodate passage through the birth canal, the fetal skull is compressed and reshaped, a phenomenon known as molding. The fetal skull bones are separated by membranous sutures that facilitate compression and overlap, resulting in a reduced diameter. This increases the probability of a successful vaginal delivery. Fetal position, presentation, station, and attitude can be examined with ultrasound, but fetal head molding has not been previously studied with ultrasound. Objective This study aimed to describe ultrasound-assessed fetal head molding in a population of nulliparous women with slow progress in the second stage of labor and to study associations with fetal position and delivery mode. Study Design This was a secondary analysis of a population comprising 150 nulliparous women with a single fetus in cephalic presentation, with slow progress in the active second stage with pushing. Women were eligible for the study when an operative intervention was considered by the clinician. Molding was examined in stored transperineal two-dimensional and three-dimensional acquisitions and differentiated into occipitoparietal molding along the lambdoidal sutures, frontoparietal molding along the coronal sutures, and parietoparietal molding at the sagittal suture (molding in the midline). Molding could not be classified if positions were unknown, and these cases were excluded. We measured the distance from the molding to the head midline, molding step, and overlap of skull bones and looked for associations with fetal position and delivery mode. The responsible clinicians were blinded to the ultrasound findings. Results Six cases with unknown position were excluded, leaving 144 women in the study population. Fetal position was anterior in 117 cases, transverse in 12 cases, and posterior in 15 cases. Molding was observed in 79 of 144 (55%) fetuses. Molding was seen significantly more often in occiput anterior positions than in non–occiput anterior positions (69 of 117 [59%] vs 10 of 27 [37%]; P=.04). In occiput anterior positions, the molding was seen as occipitoparietal molding in 68 of 69 cases and as parietoparietal molding in 1 case with deflexed attitude. Molding was seen in 19 of 38 (50%) of occiput anterior positions ending with spontaneous delivery, 42 of 71(59%) ending with vacuum extraction, and in 7 of 8 (88%) with failed vacuum extraction (P=.13). In 4 fetuses with occiput posterior positions, parietoparietal molding was diagnosed, and successful vacuum extraction occurred in 3 cases and failed extraction in 1. Frontoparietal molding was seen in 2 transverse positions and 4 posterior positions. One delivered spontaneously; vacuum extraction failed in 3 cases and was successful in 2. Only 1 of 11 fetuses with either parietoparietal or frontoparietal molding was delivered spontaneously. Conclusion The different types of molding can be classified with ultrasound. Occipitoparietal molding was commonly seen in occiput anterior positions and not significantly associated with delivery mode. Frontoparietal and parietoparietal moldings were less frequent than reported in old studies and should be studied in larger populations with mixed ethnicities. Not available due to copyright restrictions

Introduction We aimed to examine the agreement between ultrasound and digital vaginal examination in assessing cervical dilatation in an African population and to assess the value of ultrasound in detecting active labor. Method A cross-sectional study was conducted in a teaching hospital in Ghana between April and September of 2016. Anterior–posterior and transverse diameters of cervical dilatation were measured with ultrasound and the mean value was compared with digital vaginal examination in 195 women in labor. Agreement between methods was examined with correlation coefficients and with Bland–Altman plots. Active labor was defined when cervix was dilated ≥ 4 cm with vaginal examinations. ROC curve analysis was conducted on the diagnostic performance of ultrasound in detecting active labor. Results Data were analyzed in 175 out of 195 (90%) cases where ultrasound could clearly visualize the cervix. The remaining 20 cases were all determined by digital vaginal examination as advanced cervical dilatation (≥ 8 cm), advanced head station (≥ + 2), and with ruptured membranes. The Pearson correlation coefficient (r) was 0.78 (95% CI 0.72–0.83) and the intra-class correlation coefficient was 0.76 (95% CI 0.69–0.81). Bland–Altman analysis obtained a mean difference of − 0.03 cm (95% CI − 0.18 to 0.12) with zero included in the CI intervals, indicating no significant difference between methods. Limits of agreement were from − 2.01 to 1.95 cm. Ultrasound predicted active labor with 0.87 (95% CI 0.75–0.99) as the area under the ROC curve. Conclusion Ultrasound measurements showed good agreement with digital vaginal examinations in assessing cervical dilatation during labor and ultrasound may be used to detect active labor. Open Access This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creat iveco mmons .org/licen ses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.

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.

Introduction: The aim of the study was to investigate fetal head rotation during vacuum extraction. Material and methods: We conducted a prospective cohort study from November 2013 to July 2016 in seven European hospitals. Fetal head position was determined with transabdominal or transperineal ultrasound and categorized as occiput anterior (OA), occiput transverse (OT) or occiput posterior (OP) position. Main outcome was the proportion of fetuses rotating during vacuum extraction. Secondary outcomes were conversion of delivery method, duration of vacuum extraction, umbilical artery pH

Introduction The aim was to investigate correlations between fetal weight gain/day and birthweight with blood flow estimates in the uterine arteries calculated with the PixelFlux technique and with measurements from TAmax. We also aimed to examine the agreement between estimates using the two methods. Material and methods We conducted a prospective observational pilot study in pregnancy week 24–25 in women with risk pregnancies referred to the fetal medical centre at St. Olavs Hospital, Trondheim, Norway from March 2016 to June 2016. Blood flow in the uterine arteries was calculated using time-averaged peak velocity (TAmax) and the PixelFlux technique. PixelFlux is a method based on pixelwise calculation of spatially angle-corrected velocities and areas of all pixels inside a vessel during a heart cycle. Results The mean flow calculated from PixelFlux and TAmax was 811 ml/minute and 787 ml/minute, respectively. The intra-class correlation coefficient was 0.83 (95% CI 0.72-0.90) and limits of agreement were −441 ml/minute (95% CI -558 to −324 ml/minute) to 489 ml/minute (95% CI 372 to 606 ml/minute). We observed a significant correlation between mean flow calculated from PixelFlux and birthweight (r=0.41; p Conclusions We found significant correlations between estimated blood flow in the uterine arteries using the PixelFlux technique with fetal weight-gain/day and with birthweight. Estimates from two methods showed good agreement.

To investigate associations between the duration of the active second stage of labour and adverse maternal and neonatal outcomes.This cohort study is based on data from a cluster randomised controlled trial (RCT) undertaken at 14 Norwegian birth clinics in Norway from 2014 to 2017. The final sample involved 6804 nulliparous women with a singleton fetus, cephalic presentation, spontaneous onset of labour at term, vaginal delivered and with an active second stage of labour. The women were grouped to active second stage of labour ≤ 60 min and active second stage of labour 60 min. Binary logistic regression was used to estimate crude and adjusted odds ratios (ORs) of the maternal and neonatal outcomes with an associated 95% confidence intervals (CIs), comparing women in the two groups.There was an increased risk of postpartum haemorrhage 1000 ml with an adjusted OR 1.31 (95% CI: 1.01-1.69) when the active second stage of labour exceeded 60 min. There was no significant difference in the risk of obstetric anal sphincter injuries (adjusted OR 0.93 [95% CI: 0.65-1.39]), Apgar scores 7 at 5 min age (adjusted OR 1.13 [95% CI: 0.65-1.97]) or admission to the neonatal intensive care unit (adjusted OR 1.46 [95% CI: 0.61-3.51]) between the study groups.Women with an active second stage of labour that exceeds 60 min had an increased risk of postpartum haemorrhage 1000 ml. We found no association between duration of active stage of labour and obstetric anal sphincter injuries or adverse neonatal outcomes.

Identifying predictive factors for a normal outcome at admission in the labor ward would be of value for planning labor care, timing interventions, and preventing labor dystocia. Clinical assessments of fetal head station and position at the start of labor have some predictive value, but the value of ultrasound methods for this purpose has not been investigated. Studies using transperineal ultrasound before labor onset show possibilities of using these methods to predict outcomes.This study aimed to investigate whether ultrasound measurements during the first examination in the active phase of labor were associated with the duration of labor phases and the need for operative delivery.This was a secondary analysis of a prospective cohort study at Landspitali University Hospital, Reykjavík, Iceland. Nulliparous women at ≥37 weeks' gestation with a single fetus in cephalic presentation and in active spontaneous labor were eligible for the study. The recruitment period was from January 2016 to April 2018. Women were examined by a midwife on admission and included in the study if they were in active labor, which was defined as regular contractions with a fully effaced cervix, dilatation of ≥4 cm. An ultrasound examination was performed by a separate examiner within 15 minutes; both examiners were blinded to the other's results. Transabdominal and transperineal ultrasound examinations were used to assess fetal head position, cervical dilatation, and fetal head station, expressed as head-perineum distance and angle of progression. Duration of labor was estimated as the hazard ratio for spontaneous delivery using Kaplan-Meier curves and Cox regression analysis. The hazard ratios were adjusted for maternal age and body mass index. The associations between study parameters and mode of delivery were evaluated using receiver operating characteristic curves.Median times to spontaneous delivery were 490 minutes for a head-perineum distance of ≤45 mm and 682 minutes for a head-perineum distance of45 mm (log-rank test, P=.009; adjusted hazard ratio for a shorter head-perineum distance, 1.47 [95% confidence interval, 0.83-2.60]). The median durations were 506 minutes for an angle of progression of ≥93° and 732 minutes for an angle of progression of93° (log-rank test, P=.008; adjusted hazard ratio, 2.07 [95% confidence interval, 1.15-3.72]). The median times to delivery were 506 minutes for nonocciput posterior positions and 677 minutes for occiput posterior positions (log-rank test, P=.07; adjusted hazard ratio, 1.52 [95% confidence interval, 0.96-2.38]) Median times to delivery were 429 minutes for a dilatation of ≥6 cm and 704 minutes for a dilatation of 4 to 5 cm (log-rank test, P=.002; adjusted hazard ratio, 3.11 [95% confidence interval, 1.68-5.77]). Overall, there were 75 spontaneous deliveries; among those deliveries, 16 were instrumental vaginal deliveries (1 forceps delivery and 15 ventouse deliveries), and 8 were cesarean deliveries. Head-perineum distance and angle of progression were associated with a spontaneous delivery with area under the receiver operating characteristic curves of 0.68 (95% confidence interval, 0.55-0.80) and 0.67 (95% confidence interval, 0.55-0.80), respectively. Ultrasound measurement of cervical dilatation or position at inclusion was not significantly associated with spontaneous delivery.Ultrasound examinations showed that fetal head station and cervical dilatation were associated with the duration of labor; however, measurements of fetal head station were the variables best associated with operative deliveries.

Background Ultrasound measurements offer objective and reproducible methods to measure the fetal head station. Before these methods can be applied to assess labor progression, the fetal head descent needs to be evaluated longitudinally in well-defined populations and compared with the existing data derived from clinical examinations. Objective This study aimed to use ultrasound measurements to describe the fetal head descent longitudinally as labor progressed through the active phase in nulliparous women with spontaneous onset of labor. Study Design This was a single center, prospective cohort study at the Landspitali - The National University Hospital of Iceland, Reykjavik, Iceland, from January 2016 to April 2018. Nulliparous women with a single fetus in cephalic presentation and spontaneous labor onset at a gestational age of ≥37 weeks, were eligible. Participant inclusion occurred during admission for women with an established active phase of labor or at the start of the active phase for women admitted during the latent phase. The active phase was defined as an effaced cervix dilated to at least 4 cm in women with regular contractions. According to the clinical protocol, vaginal examinations were done at entry and subsequently throughout labor, paired each time with a transperineal ultrasound examination by a separate examiner, with both examiners being blinded to the other’s results. The measurements used to assess the fetal head station were the head-perineum distance and angle of progression. Cervical dilatation was examined clinically. Results The study population comprised 99 women. The labor patterns for the head-perineum distance, angle of progression, and cervical dilatation differentiated the participants into 75 with spontaneous deliveries, 16 with instrumental vaginal deliveries, and 8 cesarean deliveries. At the inclusion stage, the cervix was dilated 4 cm in 26 of the women, 5 cm in 30 of the women, and ≥6 cm in 43 women. One cesarean and 1 ventouse delivery were performed for fetal distress, whereas the remaining cesarean deliveries were conducted because of a failure to progress. The total number of examinations conducted throughout the study was 345, with an average of 3.6 per woman. The ultrasound-measured fetal head station both at the first and last examination were associated with the delivery mode and remaining time of labor. In spontaneous deliveries, rapid head descent started around 4 hours before birth, the descent being more gradual in instrumental deliveries and absent in cesarean deliveries. A head-perineum distance of 30 mm and angle of progression of 125° separately predicted delivery within 3.0 hours (95% confidence interval, 2.5–3.8 hours and 2.4–3.7 hours, respectively) in women delivering vaginally. Although the head-perineum distance and angle of progression are independent methods, both methods gave similar mirror image patterns. The fetal head station at the first examination was highest for the fetuses in occiput posterior position, but the pattern of rapid descent was similar for all initial positions in spontaneously delivering women. Oxytocin augmentation was used in 41% of women; in these labors a slower descent was noted. Descent was only slightly slower in the 62% of women who received epidural analgesia. A nonlinear relationship was observed between the fetal head station and dilatation. Conclusion We have established the ultrasound-measured descent patterns for nulliparous women in spontaneous labor. The patterns resemble previously published patterns based on clinical vaginal examinations. The ultrasound-measured fetal head station was associated with the delivery mode and remaining time of labor.

Aims and objectives To examine whether interprofessional simulation training on management of postpartum haemorrhage enhances self-efficacy and collective efficacy and reduces the blood transfusion rate after birth. Background Postpartum haemorrhage is a leading cause of maternal morbidity and mortality worldwide, although it is preventable in most cases. Interprofessional simulation training might help improve the competence of health professionals dealing with postpartum haemorrhage, and more information is needed to determine its potential. Design Multimethod, quasi-experimental, pre–post intervention design. Methods Interprofessional simulation training on postpartum haemorrhage was implemented for midwives, obstetricians and auxiliary nurses in a university hospital. Training included realistic scenarios and debriefing, and a measurement scale for perceived postpartum haemorrhage-specific self-efficacy, and collective efficacy was developed and implemented. Red blood cell transfusion was used as the dependent variable for improved patient outcome pre–post intervention. Results Self-efficacy and collective efficacy levels were significantly increased after training. The overall red blood cell transfusion rate did not change, but there was a significant reduction in the use of ≥5 units of blood products related to severe bleeding after birth. Conclusion The study contributes to new knowledge on how simulation training through mastery and vicarious experiences, verbal persuasion and psychophysiological state might enhance postpartum haemorrhage-specific self-efficacy and collective efficacy levels and thereby predict team performance. The significant reduction in severe postpartum haemorrhage after training, indicated by reduction in ≥5 units of blood transfusions, corresponds well with the improvement in collective efficacy, and might reflect the emphasis on collective efforts to counteract severe cases of postpartum haemorrhage. Relevance to clinical practice Interprofessional simulation training in teams may contribute to enhanced prevention and management of postpartum haemorrhage, shown by a significant increase in perceived efficacy levels combined with an indicated reduction of severe postpartum haemorrhage after training.

Introduction The aim of the study was to compare the duration of active phase of labor in women with spontaneous or induced start of labor. Material and methods An observational cohort study was performed at Stavanger University Hospital in Norway between January 2010 and December 2013. During the study period 19 524 women delivered. Data for the study were collected from an electronic birth journal. Women with previous cesarean section, multiple pregnancy, breech or transverse lie, preterm labor or prelabor cesarean section were excluded. Analyses were stratified between nulliparous and parous women. Active phase of labor was defined when contractions were regular, with cervix effaced and dilated 4 cm. The main outcome measure was duration of active phase of labor. Results The active phase was longer in induced labors than in labors with spontaneous onset in nulliparous women. The estimated median duration using survival analyses was 433 min (95% confidence interval 419–446) in spontaneous vs. 541 min (95% confidence interval 502–580) in induced labors [unadjusted hazard ratio 0.76 (95% confidence interval 0.71–0.82) and adjusted hazard ratio 0.88 (95% confidence interval 0.82–0.95)]. In parous women, a one minus survival plot showed that induced labors had shorter duration before six hours in active labor, but after six hours, induced labors had longer duration. The overall difference in parous women was small and probably of little clinical importance. Conclusion The active phase of labor was longer in induced than in spontaneous labors in nulliparous women. This is the pre-peer reviewed version of the following article: [Duration of the active phase of labor in spontaneous and induced labors], which has been published in final form at http://onlinelibrary.wiley.com/doi/10.1111/aogs.13039/epdf. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.

Objective A decrease of obstetric anal sphincter injuries (OASIS) was observed after preventive interventions were implemented at a Norwegian university hospital. The aim was to investigate whether the improvement had sustained over the following years. Materials and methods We performed a retrospective cohort study of 18 258 singleton vaginal cephalic births, ≥37 + 0 weeks of gestation during 2012–2017, examining data from the hospital’s birth journals and separate registration forms. Interventions to prevent OASIS were implemented in 2011, and training in practical skills was repeated each year. Main outcome measures The main outcome was OASIS (n = 377). Results Frequency of OASIS overall decreased from 3.6% prior to 2011 to 2.1% after the intervention and sustained at that level throughout the study period. A trend of fewer OASIS among spontaneous deliveries, decreasing from 2.1% to 1.2% (p = 0.01) was observed, but no trend was seen for instrumental deliveries (p = 0.37), where the incidence fluctuated between 4.0% and 9.3% with an average of 6.5%. Primiparity, increased maternal age and increased fetal head circumference were associated with more OASIS in spontaneous deliveries. In instrumental deliveries, primiparity, occiput posterior position and increased fetal head circumference were associated with more OASIS, whilst episiotomy was associated with fewer OASIS. Conclusion The incidence of obstetric anal sphincter injuries maintained at a similar level of around 2.1% during the six following years after introducing preventive interventions. Regularly repetition and practical training seemed to be effective.

Introduction: This study aims to investigate the use of oxytocin augmentation during labor in nulliparous women following Zhang’s guideline or the WHO partograph. Material and methods: This is a secondary analysis of a cluster randomized controlled trial in 14 birth care units in Norway, randomly assigned to either the intervention group, which followed Zhang’s guideline, or to the control group, which followed the WHO partograph, for labor progression. The participants were nulliparous women who had a singleton full-term fetus in a cephalic presentation and spontaneous onset of labor, denoted as group 1 in the Ten Group Classification System. Results: Between December 2014 and January 2017, 7277 participants were included. A total of 3219 women (44%) were augmented with oxytocin during labor. Oxytocin was used in 1658 (42%) women in the Zhang group compared with 1561 (47%) women in the WHO group. The adjusted relative risk for augmentation with oxytocin was 0.98, 95% CI; 0.84 to 1.15; P=0.8 in the Zhang versus WHO group, with an adjusted risk difference of −0.8 %, 95% CI; −7.8 to 6.1. The participants in the Zhang group were less likely to be augmented with oxytocin prior to 6 centimeters of cervical dilatation (24%) compared with participants in the WHO group (28%), with an adjusted relative risk of 0.84, 95% CI; 0.75 to 0.94; P=0.003. Oxytocin was administrated almost 20 minutes longer in the Zhang group than in the WHO group, with an adjusted mean difference of 17.9, 95% CI; 2.7 to 33.1; P=0.021 minutes. In addition, 19% of the women in the Zhang group and 23% in the WHO group were augmented with oxytocin without being diagnosed with labor dystocia. Conclusions: Although no significant difference in the proportion of oxytocin augmentation was observed between the two study groups, there were differences in how oxytocin was used. Women in the Zhang group were less likely to be augmented with oxytocin prior to 6 centimeters of cervical dilatation. The duration of augmentation with oxytocin was longer in the Zhang group than in the WHO group. This study was funded by the Research Department, Østfold Hospital Trust, Norway and the Faculty of Health Sciences, Department of Nursing and Health Promotion, OsloMet – Oslo Metropolitan University, Oslo, Norway.

OBJECTIVES: To investigate if descent of the fetal head during active pushing is associated with duration of operative vaginal delivery, mode of delivery and neonatal outcome in nulliparous women with prolonged second stage of labor. METHODS: This was a prospective cohort study of nulliparous women with prolonged second stage of labor, conducted between November 2013 and July 2016 in five European countries. Fetal head descent was measured using transperineal ultrasound. Head-perineum distance (HPD) was measured between contractions and on maximum contraction during active pushing, and the difference between these values (ΔHPD) was calculated. The main outcome was duration of operative vaginal delivery, estimated using survival analysis to calculate hazard ratios (HRs) for vaginal delivery, with values > 1 indicating a shorter duration. HR was adjusted for prepregnancy body mass index, maternal age, induction of labor, augmentation with oxytocin and use of epidural analgesia. Pregnancies were grouped according to ΔHPD quartile, and delivery mode and neonatal outcome were compared between groups. RESULTS: The study population comprised 204 women. Duration of vacuum extraction was shorter with increasing ΔHPD. Estimated mean duration was 10.0, 9.0, 8.8 and 7.5 min in pregnancies with ΔHPD in the first to fourth quartiles, respectively, and the adjusted HR for vaginal delivery, using increasing ΔHPD as a continuous variable, was 1.04 (95% CI, 1.01-1.08). Mean ΔHPD was 7 mm (range, -10 to 37 mm). ΔHPD was either negative or ≤ 2 mm in the lowest quartile. In this group, 7/50 (14%) pregnancies were delivered by Cesarean section, compared with 8/154 (5%) of those with ΔHPD > 2 mm (P

Objective: To investigate labour duration in different phases of labour when adhering to Zhang’s guideline for labour progression compared with the WHO partograph. Design: A secondary analysis of a cluster randomised controlled trial. Setting: Fourteen Norwegian birth care units, each with more than 500 deliveries per year constituted the clusters. Participants: A total of 7277 nulliparous women with singleton foetus in a cephalic presentation and spontaneous onset of labour at term were included. Intervention: Seven clusters were randomised to the intervention group that adhered to Zhang’s guideline (n = 3972) and seven to the control group that adhered to the WHO partograph (n = 3305) for labour progression. Measurements: The duration of labour from the first registration of cervical dilatation (≥ 4 cm) to the delivery of the baby and the duration of the first and second stages of labour; the time-to-event analysis was used to compare the duration of labour between the two groups after adjusting for baseline covariates. Findings: The adjusted median duration of labour was 7.0 h in the Zhang group, compared with 6.2 h in the WHO group; the median difference was 0.84 h with 95% confidence interval [CI] (0.2–1.5). The adjusted median duration of the first stage was 5.6 h in the Zhang group compared with 4.9 h in the WHO group; the median difference was 0.66 h with 95% CI (0.1–1.2). The corresponding adjusted median duration of the second stage was 88 and 77 min; the median difference was 0.18 h with 95% CI (0.1–0.3). Key Conclusions: The women who adhered to Zhang’s guideline had longer overall duration and duration of the first and second stages of labour than women who adhered to the WHO partograph. Implications for practice: : Understanding the variations in the duration of labour is of great importance, and the results offer useful insights into the different labour progression guidelines, which can inform clinical practice. This study was funded by the Research Department, Østfold Hospital Trust, Norway and the Faculty of Health Sciences, Department of Nursing and Health Promotion, OsloMet – Oslo Metropolitan University, Oslo, Norway.

Objectives: Exact knowledge of fetal station and position is of paramount importance for reliable surveillance of labor progress and a prerequisite for safe operative vaginal procedures. Detailed clinical assessments are thoroughly described in old textbooks, but almost forgotten in contemporary obstetrics. Ultrasound is suggested as an objective diagnostic tool in active labor. Several publications have demonstrated a low correlation between ultrasound and clinical assessment of fetal head station and position, but the methods of clinical assessment in these studies are poorly described. We wanted to explore if a quality clinical assessment could perform better than clinical assessment in previous publications, by analyzing the correlation between a structured method of clinical assessment and intrapartum ultrasound. Methods: In all, 100 laboring women with cervical dilatation ≥7 cm were included in a prospective cohort study at Oslo University Hospital-Ullevål from October to December 2016. The study design was cross-sectional. Clinical examinations were performed by one special educated consultant (JKI), and transabdominal and transperineal ultrasound clips were recorded and examined by a blinded expert in intrapartum ultrasound (TME). Fetal position was classified as a clock face with 12 units (hourly divisions) and thereafter categorized as occiput anterior (OA), left occiput transverse (LOT), occiput posterior (OP), and right occiput transverse (ROT) positions. Fetal station was categorized clinically from −5 to +5 and measured with ultrasound as angle of progression (AoP) and head-perineum distance (HPD). AoP is the angle between a longitudinal line through the symphysis and a tangent to the head contour. HPD is the shortest distance between the fetal skull and the perineum. Results: Eight women were excluded due to strong contractions between clinical assessments and ultrasound measurements, fetal distress, or incomplete examinations. Fetal position assessed with ultrasound and clinical examination agreed exactly in 48/92 (52%) of cases, within one unit (hour) in 87/92 (95%) of cases and within two units in 90/92 (98%) of cases. It differed by three units in one case and by five units in one case. The agreement categorized into OA, LOT, OP, and ROT was good (Cohen’s kappa 0.72; 95% CI 0.61–0.84). For station, the agreement was very good for both HPD (Pearson correlation coefficient r = 0.86; 95% CI 0.80–0.91) and AoP (r = 0.77; 95% CI to 0.67–0.84). The correlation between HPD and AoP was good (r = 0.76; 95% CI 0.65–0.84). Conclusion: We found very good correlations between structured clinical assessments and ultrasound examinations, suggesting that an objective quality in clinical examinations is possible to achieve. More focus on clinical skills training may improve accuracy for clinicians.

Objectives: Maternal intra-abdominal pressure and hemodynamics change during pregnancy. The left renal vein may be compressed between the uterus and the spine and aorta, causing congestion and impa...

INTRODUCTION: To compare the duration of vacuum and forceps delivery in relation to ultrasound assessment of fetal head position and station. METHODS: A prospective single‐centre cohort study in nulliparous women at term with prolonged second stage of labour. Fetal head position was determined using transabdominal ultrasound and station as head‐perineum distance (HPD) from transperineal ultrasound prior to an instrument. The primary outcome was duration of vacuum and forceps to vaginal delivery and was analysed as survival expressed by hazard ratio (HR). Secondary outcomes were delivery mode and immediate neonatal outcome. RESULTS: In the study population of 54 women, the primary instrument was vacuum for 36 and forceps for 18. Four women were delivered by Caesarean section. Estimated median duration for forceps deliveries was 5 min (95% CI 4.0–6.0) vs. 9 min (95% CI 7.3–10.6) for vacuum deliveries (P = 0.17; Log‐rank test). The HR for vaginal delivery was 2.02 (95% CI 1.04–3.91, P = 0.038) after adjusting for HPD, maternal age and BMI. OP position had minor influence on the primary outcome (HR changed from 2.02 to 2.08). The first instrument failed in 11/31 (35.5%) where HPD > 35 mm vs. 2/21 (9.5%) where HPD ≤ 35 mm (P

OBJECTIVE To explore changes in volume flow in the umbilical vein in healthy second-trimester fetuses. METHODS This was a prospective observational pilot study performed at Stavanger University Hospital, Norway, between May and October 2013. Serial three-dimensional ultrasound recordings from the umbilical vein were acquired every 30 s in a 5-min period in 43 fetuses at 17-20 weeks' gestation. The recordings were analyzed with pixelwise spatially angle-corrected volume flow measurements. RESULTS We observed variation in the umbilical vein volume flow in all fetuses, ranging from a mean minimum of 1.01 mL/s to a mean maximum of 2.60 mL/s. The minimum of all measurements was 57% compared with the mean value and the maximum was 148% of the mean value. The individual flow volume measurements ranged between 0.11 and 4.14 mL/s (mean, 1.76 mL/s). Within this range, an undulating course of all perfusion parameters was observed, with a full period of 4-5 min duration. CONCLUSION Healthy second-trimester fetuses show cyclical variation in blood flow in the umbilical vein. Copyright © 2015 ISUOG. Published by John Wiley & Sons Ltd.

Summary Background There is an ongoing debate concerning which guidelines and monitoring tools are most beneficial for assessing labour progression, to help prevent use of intrapartum caesarean section (ICS). The WHO partograph has been used for decades with the assumption of a linear labour progression; however, in 2010, Zhang introduced a new guideline suggesting a more dynamic labour progression. We aimed to investigate whether the frequency of ICS use differed when adhering to the WHO partograph versus Zhang's guideline for labour progression. Methods We did a multicentre, cluster-randomised controlled trial at obstetric units in Norway, and each site was required to deliver more than 500 fetuses per year to be eligible for inclusion. The participants were nulliparous women who had a singleton, full-term fetus with cephalic presentation, and who entered spontaneous active labour. The obstetric units were treated as clusters, and women treated within these clusters were all given the same treatment. We stratified these clusters by size and number of previous caesarean sections. The clusters containing the obstetric units were then randomly assigned (1:1) to the control group, which adhered to the WHO partograph, or to the intervention group, which adhered to Zhang's guideline. The randomisation was computer-generated and was done in the Unit of Biostatistics and Epidemiology, Oslo University Hospital, Oslo, Norway, and investigators in this unit had no further involvement in the trial. Our study design did not enable masking of participants or health-care providers, but the investigators who were analysing the data were masked to group allocation. The primary outcome was use of ICS during active labour (cervical dilatation of 4–10 cm) in all participating women. The Labour Progression Study (LaPS) is registered with ClinicalTrials.gov, number NCT02221427. Findings Between Aug 1, 2014, and Sept 1, 2014, 14 clusters were enrolled in the LaPS trial, and on Sept 11, 2014, seven obstetric units were randomly assigned to the control group (adhering to the WHO partograph) and seven obstetric units were randomly assigned to the intervention group (adhering to Zhang's guideline). Between Dec 1, 2014, and Jan 31, 2017, 11 615 women were judged to be eligible for recruitment in the trial, which comprised 5421 (46·7%) women in the control group units and 6194 (53·3%) women in the intervention group units. In the control group, 2100 (38·7%) of 5421 women did not give signed consent to participate and 16 (0·3%) women abstained from participation. In the intervention group, 2181 (35·2%) of 6194 women did not give signed consent to participate and 41 (0·7%) women abstained from participation. 7277 (62·7%) of 11 615 eligible women were therefore included in the analysis of the primary endpoint. Of these women, 3305 (45·4%) participants were in an obstetric unit that was randomly assigned to the control group (adhering to the WHO partograph) and 3972 (54·6%) participants were in an obstetric unit that was randomly assigned to the intervention group (adhering to Zhang's guideline). No women dropped out during the trial. Before the start of the trial, ICS was used in 9·5% of deliveries in the control group obstetric units and in 9·3% of intervention group obstetric units. During our trial, there were 196 (5·9%) ICS deliveries in women in the control group (WHO partograph) and 271 (6·8%) ICS deliveries in women in the intervention group (Zhang's guideline), and the frequency of ICS use did not differ between the groups (adjusted relative risk 1·17, 95% CI 0·98–1·40; p=0·08; adjusted risk difference 1·00%, 95% CI −0·1 to 2·1). We identified no maternal or neonatal deaths during our study. Interpretation We did not find any significant difference in the frequency of ICS use between the obstetric units assigned to adhere to the WHO partograph and those assigned to adhere to Zhang's guideline. The overall decrease in ICS use that we observed relative to the previous frequency of ICS use noted in these obstetric units might be explained by the close focus on assessing labour progression more than use of the guidelines. Our results represent an important contribution to the discussion on implementation of the new guideline. Funding Ostfold Hospital Trust.