BACKGROUND: Friedman\'s standards, developed almost 50 years ago, may no longer align with the needs of today\'s obstetric population and current pregnancy management practices. This study aims to analyze contemporary labor patterns and estimate labor duration in China, focusing on first-stage labor data from Chinese parturients with a spontaneous onset of labor.
METHODS: This retrospective observational study utilized data from electronic medical records of a tertiary hospital in Changsha, Hunan. Out of a total of 2,689 parturients, exclusions were made for multiple gestations, preterm, post-term, or stillbirth, cesarean delivery, non-vertex presentation, and neonatal intensive care unit admission. Average labor curves were constructed by parity using repeated-measure analysis, and labor duration was estimated through interval-censored regression, stratified by cervical dilation at admission. We performed an analysis to assess the impact of oxytocin augmentation and amniotomy on labor progression and conducted a sensitivity analysis using women with complicated outcomes.
RESULTS: Nulliparous women take over 180 minutes for cervical dilation from 3 to 4 cm, and the duration from 5 to 6 cm exceeds 145 minutes. Multiparous women experience shorter labor durations than nulliparous. Labor acceleration is observed after 5 cm in nulliparous, but no distinct inflection point is evident in the average labor curve. In the second stage of labor, the 95th percentile for nulliparous, with and without epidural analgesia, is 142 minutes and 127 minutes, respectively.
CONCLUSIONS: These findings provide valuable insights for the reassessment of labor and delivery processes in contemporary obstetric populations, including current Chinese obstetric practice.

Labour care must balance aspirations of parents with vigilance for unanticipated calamities. The \'on-site midwife-led primary care birth unit\' facilitates this. The World Health Organization have replaced the traditional partograph with the \'Labour Care Guide\'. An implementation project in Botswana included the mnemonic COPE: Companion, Oral fluids, Pain relief and Eliminate the supine position. The Parto-Ma project in Tanzania used guidelines, training and support to improve childbirth outcomes. We list labour practices supported by recent evidence, and highlight new developments. Foetal macrosomia increases risk but mistaken diagnosis increases caesarean births. Obstructed labour is a complex clinical diagnosis, and is difficult to predict. For shoulder dystocia prioritise delivery of the posterior shoulder, facilitated if needed by posterior axilla sling traction. \'Extended balloon labour induction\' with two or three Foley catheters side by side, may reduce risks associated with uterine stimulants. Bedside ultrasound may facilitate the diagnosis of cephalic malpositions and malpresentations.

OBJECTIVE: Labor is shorter in multiparous women. However, there are no individualized data on differences in duration of labor for consecutive deliveries in the same parturient.
METHODS: We conducted a retrospective data analysis from 2004 to 2021 at the University Hospital of Zurich and included all women with 2 or more vaginal deliveries of a singleton child in cephalic position, between 22 and 42 weeks of gestation. Descriptive statistics were performed with SPSS version 25.0 (IBM, SPSS Inc., USA). The primary endpoint was the ratio between durations of labor stages in consecutive deliveries of the same parturient.
RESULTS: A total of 3344 women with 7066 births (2601 first [P0], 2987 s [P1], 1176 third [P2], and 302 fourth [P3]) were included. The ratio of duration of the active first stage of labor between P1 and P0 was 0.49 (95% CI 0.47-0.51, p < 0.001) meaning that the active first stage of labor was 51% shorter. The second stage of labor with a ratio of 0.26 (95% CI 0.24-0.27, p < 0.001) was 74% shorter in P1 compared to P0. Higher birthweight of the first child led to an even greater decrease in duration of the second stage of labor in P1 compared to P0 (p = 0.003). Neuraxial anesthesia was an independent risk factor for a longer duration of labor, irrespective of parity (p < 0.001). Birthweight and HC of the neonates did not significantly differ between the children born by the same women. However, higher birthweight in of the first child significantly augmented the rate of second stage of labor between P0 and P1 (p = 0.003).
CONCLUSIONS: Up to the third delivery, duration of labor decreased with each consecutive delivery of the same parturient. An individualized assessment of the expected duration of labor in multiparous women should be encouraged.

OBJECTIVE: To determine the reliability of the Carousel simulator in medical education for obstetric examinations. Cervical dilation examination training in pregnant women exposes patients to additional uncomfortable and health-risk procedures, a gold standard, and does not objectively evaluate the medical student\'s competence.
METHODS: We studied the reliability of training internship medical students in obstetrics. Participating students were assigned to take the examination of digital assessment of the cervical dilation on the simulator. Classes performed 12 consecutive randomly blind predetermined cervical dilation examinations using the Carousel simulator. The exact answer and the answer with certainty within ±1 cm were registered and analyzed. Incorrect or outlier answers were considered with a cutoff of ≥2 cm from the dilation. A dispersion graph for each centimeter of dilation simulation was constructed.
RESULTS: Sixty-six medical obstetricians took part, performing 396 examinations. Thus, we observed 49 outliers (12.37%) in simulated assessments. According to the analysis, we did not observe outliers from dilation 1 to 4 cm; dilation 7 to 9 cm had a higher index of outlier measurements. We did not consider any dilation simulation dispersion graphic as a null correlation. A strong correlation was seen in the dilation 1 to 6 cm and the dilation 10 cm. The dilations 7, 8, and 9 cm showed a weak correlation.
CONCLUSIONS: The Carousel simulator model is a reliable method for student learning. The simulator is an essential study tool capable of reducing the embarrassment and possible harm caused by the excessive and repetitive number of in vivo digital vaginal examinations. Novel studies are proposed to improve the simulator device and method, mainly to estimate the adequate repetitions and training needed before in vivo practice.

Studies on noninvasive factors and predicting the maintenance of pregnancy, and those comparing the usefulness of these factors with invasive amniotic fluid markers in predicting the maintenance of pregnancy following rescue cerclage, are lacking. Therefore, this study aimed to determine whether C-reactive protein (CRP) levels, White blood cell (WBC) count, absolute neutrophil count (ANC), and platelet-to-lymphocyte ratio (PLR) in maternal blood, which are noninvasive and readily available clinical markers, can predict the maintenance of pregnancy following rescue cerclage in patients with cervical insufficiency (CI). A total of 142 singleton pregnant women (15-28 wk) who underwent rescue cerclage for CI were retrospectively evaluated. The interleukin (IL)-6 concentration in the amniotic fluid; CRP levels, WBC count, ANC, and PLR in the maternal peripheral blood; and degree of cervical dilatation were evaluated before cerclage. The primary outcome was whether the pregnancy was maintained for >4 weeks after rescue cerclage. Among the 142 patients, prolonged pregnancy for >4 weeks following emergent cerclage was observed in 107 (75.35%), while 35 (24.65%) gave birth within 4 weeks. This study demonstrated that the degree of cervical dilatation at diagnosis; WBC count, ANC, and CRP levels in the maternal peripheral blood; and IL-6 concentration in the amniotic fluid significantly differed between the successful and failure groups (all P < .05). The area under the curve (AUC) of the amniotic fluid IL-6 concentration was .795 for the prediction of spontaneous preterm birth within 4 weeks after rescue cerclage. Additionally, the AUC of the CRP level, cervical dilatation, WBC count, ANC, and PLR were .795, .703, .695, .682, and .625, respectively. These findings suggest that the preoperative CRP levels can be considered a useful noninvasive marker comparable to amniotic fluid IL-6 concentration for identifying pregnant women with CI at high risk of spontaneous preterm birth following rescue cerclage.

OBJECTIVE: This systematic scoping review was conducted to 1) identify and describe labor curves that illustrate cervical dilatation over time; 2) map any evidence for, as well as outcomes used to evaluate the accuracy and effectiveness of the curves; and 3) identify areas in research that require further investigation.
METHODS: A three-step systematic literature search was conducted for publications up to May 2023. We searched the Medline, Maternity & Infant Care, Embase, Cochrane Library, Epistemonikos, CINAHL, Scopus, and African Index Medicus databases for studies describing labor curves, assessing their effectiveness in improving birth outcomes, or assessing their accuracy as screening or diagnostic tools. Original research articles and systematic reviews were included. We excluded studies investigating adverse birth outcomes retrospectively, and those investigating the effect of analgesia-related interventions on labor progression. Study eligibility was assessed, and data were extracted from included studies using a piloted charting form. The findings are presented according to descriptive summaries created for the included studies.
UNASSIGNED: Of 26,073 potentially eligible studies, 108 studies were included. Seventy-three studies described labor curves, of which ten of the thirteen largest were based mainly on the United States Consortium on Safe Labor cohort. Labor curve endpoints were 10 cm cervical dilatation in 69 studies and vaginal birth in 4 studies. Labor curve accuracy was assessed in 26 studies, of which all 15 published after 1986 were from low- and middle-income countries. Recent studies of labor curve accuracy in high-income countries are lacking. The effectiveness of labor curves was assessed in 13 studies, which failed to prove the superiority of any curve. Patient-reported health and well-being is an underrepresented outcome in evaluations of labor curves. The usefulness of labor curves is still a matter of debate, as studies have failed to prove their accuracy or effectiveness.

The second stage of labor extends from complete cervical dilatation to delivery. During this stage, descent and rotation of the presenting part occur as the fetus passively negotiates its passage through the birth canal. Generally, descent begins during the deceleration phase of dilatation as the cervix is drawn upward around the fetal presenting part. The most common means of assessing the normality of the second stage of labor is to measure its duration, but progress can be more meaningfully gauged by measuring the change in fetal station as a function of time. Accurate clinical identification and evaluation of differences in patterns of fetal descent are necessary to assess second stage of labor progress and to make reasoned judgments about the need for intervention. Three distinct graphic abnormalities of the second stage of labor can be identified: protracted descent, arrest of descent, and failure of descent. All abnormalities have a strong association with cephalopelvic disproportion but may also occur in the presence of maternal obesity, uterine infection, excessive sedation, and fetal malpositions. Interpretation of the progress of fetal descent must be made in the context of other clinically discernable events and observations. These include fetal size, position, attitude, and degree of cranial molding and related evaluations of pelvic architecture and capacity to accommodate the fetus, uterine contractility, and fetal well-being. Oxytocin infusion can often resolve an arrest or failure of descent or a protracted descent caused by an inhibitory factor, such as a dense neuraxial block. It should be used only if thorough assessment of fetopelvic relationships reveals a low probability of cephalopelvic disproportion. The value of forced Valsalva pushing, fundal pressure, and routine episiotomy has been questioned. They should be used selectively and where indicated.

OBJECTIVE: Well-established clinical practice for assessing progress in labor involves routine abdominal palpation and vaginal examination (VE). However, VE is subjective, poorly reproducible and painful for most women. In this study, our aim was to evaluate the feasibility of systematically integrating transabdominal and transperineal ultrasound assessment of fetal position, parasagittal angle of progression (psAOP), head-perineum distance (HPD) and sonographic cervical dilatation (SCD) to monitor the progress of labor in women undergoing induction of labor (IOL). We also aimed to determine if ultrasound can reduce women\'s pain during such examinations.
METHODS: Women were recruited as they presented for IOL in three maternity units. Ultrasound assessments were performed in 100 women between 37 + 0 and 41 + 6 weeks\' gestation. A baseline combined transabdominal and transperineal scan was performed, including assessment of fetal biometry, umbilical artery and fetal middle cerebral artery Doppler, amniotic fluid index, fetal spine and occiput positions, psAOP, HPD, SCD and cervical length. Intrapartum scans were performed instead of VE, unless there was a clinical indication to perform a VE, according to protocol. Participants were asked to indicate their level of pain by verbally giving a pain score between 0 and 10 (with 0 representing no pain) during assessment. Repeated measures data were analyzed using mixed-effect models to identify significant factors that affected the relationship between psAOP, HPD, SCD and mode of delivery.
RESULTS: A total of 100 women were included in the study. Of these, 20% delivered by Cesarean section, 65% vaginally and 15% by instrumental delivery. There were no adverse fetal or maternal outcomes. A total of 223 intrapartum ultrasound scans were performed in 87 participants (13 women delivered before intrapartum ultrasound was performed), with a median of two scans per participant (interquartile range (IQR), 1-3). Of these, 76 women underwent a total of 151 VEs with a median of one VE per participant (IQR, 0-2), with no significant difference between vaginal- or Cesarean-delivery groups. After excluding those with epidural anesthesia during examination, the median pain score for intrapartum scans was 0 (IQR, 0-1) and for VE it was 3 (IQR, 0-6). Cesarean delivery was significantly associated with a slower rate of change in psAOP, HPD and SCD.
CONCLUSIONS: Comprehensive transabdominal and transperineal ultrasound assessment can be used to assess progress in labor and can reduce the level of pain experienced during examination. Ultrasound assessment may be able to replace some transabdominal and vaginal examinations during labor. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

The diagnosis of failure to progress, the most common indication for intrapartum cesarean delivery, is based on the assessment of cervical dilation and station over time. Labor curves serve as references for expected changes in dilation and fetal descent. The labor curves of Friedman, Zhang et al, and others are based on time alone and derived from mothers with spontaneous labor onset. However, labor induction is now common, and clinicians also consider other factors when assessing labor progress. Labor curves that consider the use of labor induction and other factors that influence labor progress have the potential to be more accurate and closer to clinical decision-making.
This study aimed to compare the prediction errors of labor curves based on a single factor (time) or multiple clinically relevant factors using two modeling methods: mixed-effects regression, a standard statistical method, and Gaussian processes, a machine learning method.
This was a longitudinal cohort study of changes in dilation and station based on data from 8022 births in nulliparous women with a live, singleton, vertex-presenting fetus ≥35 weeks of gestation with a vaginal delivery. New labor curves of dilation and station were generated with 10-fold cross-validation. External validation was performed using a geographically independent group. Model variables included time from the first examination in the 20 hours before delivery; dilation, effacement, and station recorded at the previous examination; cumulative contraction counts; and use of epidural anesthesia and labor induction. To assess model accuracy, differences between each model\'s predicted value and its corresponding observed value were calculated. These prediction errors were summarized using mean absolute error and root mean squared error statistics.
Dilation curves based on multiple parameters were more accurate than those derived from time alone. The mean absolute error of the multifactor methods was better (lower) than those of the single-factor methods (0.826 cm [95% confidence interval, 0.820-0.832] for the multifactor machine learning and 0.893 cm [95% confidence interval, 0.885-0.901] for the multifactor mixed-effects method and 2.122 cm [95% confidence interval, 2.108-2.136] for the single-factor methods; P<.0001 for both comparisons). The root mean squared errors of the multifactor methods were also better (lower) than those of the single-factor methods (1.126 cm [95% confidence interval, 1.118-1.133] for the machine learning [P<.0001] and 1.172 cm [95% confidence interval, 1.164-1.181] for the mixed-effects methods and 2.504 cm [95% confidence interval, 2.487-2.521] for the single-factor [P<.0001 for both comparisons]). The multifactor machine learning dilation models showed small but statistically significant improvements in accuracy compared to the mixed-effects regression models (P<.0001). The multifactor machine learning method produced a curve of descent with a mean absolute error of 0.512 cm (95% confidence interval, 0.509-0.515) and a root mean squared error of 0.660 cm (95% confidence interval, 0.655-0.666). External validation using independent data produced similar findings.
Cervical dilation models based on multiple clinically relevant parameters showed improved (lower) prediction errors compared to models based on time alone. The mean prediction errors were reduced by more than 50%. A more accurate assessment of departure from expected dilation and station may help clinicians optimize intrapartum management.

OBJECTIVE: To explore the relationship between the duration of transition from latent to active labor and various obstetric, maternal, fetal, and neonatal outcomes.
METHODS: A retrospective cohort study was conducted on term, singleton deliveries at Soroka University Medical Center from 2013 to 2018. Data were extracted from electronic medical records. The exposure variable was defined as prolonged transition, which was itself defined as the upper 10th centile of dilation duration from 4 to 6 cm. Clinical and demographic characteristics were compared using χ2 test. Multivariate logistic regression was used to estimate the contribution of a prolonged transition with each adverse outcome adjusting for potential confounders.
RESULTS: In all, 12 104 deliveries met the inclusion criteria. The mean ± standard deviation of duration of dilation from 4 to 6 cm was 03:07:58 ± 03:03:42 (hours:minutes:seconds). Progress curves varied significantly among patients with different obstetrical and demographic characteristics. Prolonged transition was significantly linked to an increased risk of cesarean delivery (adjusted odds raito 2.607, 95% confidence interval 2.171-3.130, area under the curve 0.689) and higher rates of maternal and neonatal morbidity.
CONCLUSIONS: Patients experiencing transition phases exceeding the 90th centile faced an elevated risk of cesarean delivery and postpartum complications. Future studies should focus on interventions during the transition phase to improve pregnancy outcomes and enhance patient safety.