Adoption of Consensus Guidelines for Safe Prevention of the Primary Cesarean Delivery by Freestanding Birth Centers

INTRODUCTION

Slow or arrested progress in labor is the most frequent (64%) indication for nonemergent transfer of laboring people from freestanding birth centers to the hospital. After the 2014 publication of the Consensus Statement on Safe Prevention of Primary Cesarean Delivery (Consensus Statement), many freestanding birth centers changed their clinical practice guidelines to allow more time for active labor in the birth center prior to hospital transfer. The result of these changes has not been evaluated in birth centers. Evaluation of adoption of guidelines based on the Consensus Statement in hospitals has shown inconsistent results.

METHODS

Birth centers were contacted to determine whether they changed clinical practice guidelines in response to the Consensus Statement. A before-after analysis compared outcomes for the 2 calendar years before and the 2 calendar years after adoption of new guidelines with a retrospective analysis of deidentified client-level data collected in the American Association of Birth Centers Perinatal Data Registry.

RESULTS

A third of responding birth centers (11 of 33) changed their clinical practice guidelines, mostly redefining the onset of active labor as beginning at 6 cm cervical dilatation and allowing 4 hours of arrest of dilatation in active labor before transfer to the hospital. These changes were associated with fewer diagnoses of prolonged first stage of labor (13.8% vs 8.0%, P < .01) but not with fewer intrapartum transfers (14.0% vs 14.7%, P = .55) or cesarean births (5.0 vs 4.1%, P = .26.) DISCUSSION: We found no evidence that making these practice changes was associated with better outcomes. Two hours of a lack of documented cervical change in active labor is likely long enough to diagnose arrested progress in labor. Research on proportion of morbidity and mortality associated with prolonged labor could inform practice guidelines for transfers.

Spontaneous labor curve based on a retrospective multi-center study in Japan

Aim

In Japan, the criteria of the latent and active phases of the first stage of labor have not been decided. The Japan Society of Obstetrics and Gynecology (JSOG) Perinatal Committee conducted a study to construct a spontaneous labor curve in order to determine the point of onset of the active phase.

Methods

The participants were women who had spontaneous deliveries at four health facilities in Japan between September 1, 2011, and September 31, 2019. Spontaneous delivery was defined as the spontaneous onset of labor at term (37 weeks, 0 days to 41 weeks, 6 days) with vaginal delivery of a mature fetus in a cephalic position without uterotonic agents or epidural analgesia. The time points for each “cm” of dilation were collected starting from the time of full dilation retrogradely. The relationship between time since labor onset and cervical dilation was expressed as a curve using a smoothing B‐spline.

Results

A total of 4215 primiparous and 5266 multiparous women were included in this study. The spontaneous labor curve showed that in both primiparous and multiparous women, labor progress was slow until 5 cm cervical dilation, accelerating between 5 and 6 cm dilation, and steadily progressed after 6 cm dilation.

Conclusion

We propose that the active phase of the first stage of labor be defined as starting at 5 cm dilation of the cervix, and that it be divided into an acceleration phase (5–6 cm dilation) and a maximal phase (>6 cm dilation).

Review of Evidence-Based Methods for Successful Labor Induction

Induction of labor is increasingly a common component of the intrapartum care. Knowledge of the current evidence on methods of labor induction is an essential component of shared decision-making to determine which induction method meets an individual's health needs and personal preferences. This article provides a review of the current research evidence on labor induction methods, including cervical ripening techniques, and contraction stimulation techniques. Current evidence about expected duration of labor following induction, use of the Bishop score to guide induction, and guidance on the use of combination methods for labor induction are reviewed.

Process of fetal head descent as recorded by ultrasonography: How does this compare with the conventional first stage of labor?

OBJECTIVE

To construct an ultrasound partogram using serial transperineal sonographic measurements of the angle of fetal head progression during the first stage of labor, and to compare it with a conventional partogram based on digital vaginal examinations.

METHODS

Between 2017 and 2018, a prospective cohort study at Drum Tower Hospital, Nanjing, China, recruited 375 nulliparous women with singleton pregnancy and spontaneous onset of labor at 37 or more gestational weeks. Transperineal ultrasound scans were performed to measure the angle of progression (AoP) every 0.5-1 h until the second stage. Vaginal examinations were also used to measure cervical dilatation. Repeated-measures analysis was used to generate labor curves.

RESULTS

The labor curve generated by AoP had a pattern similar to that based on cervical dilatation. There was an initial slow period lasting approximately 5.5 h until the cervical dilatation or AoP reached the inflection point (4 cm and 119°, respectively), followed by a second, more rapid period, lasting approximately 2.5 h.

CONCLUSION

Based on ultrasound data, it was feasible to construct an "angle of progression partogram" of the first stage of labor, which was similar in pattern to the partogram based on cervical dilatation measured in the same cohort.

Association of abnormal first stage of labor duration and maternal and neonatal morbidity

BACKGROUND

Contemporary guidelines for labor management do not characterize abnormal labor on the basis of maternal and/or neonatal morbidity.

OBJECTIVE

In this study, we aimed to evaluate the association of abnormal duration of the first stage of term labor and the risk of maternal and neonatal morbidity.

STUDY DESIGN

We conducted a retrospective analysis of prospectively collected data of all consecutive women admitted for delivery at a single center at ≥37 weeks and 0 to 7 days of gestation with singleton, nonanomalous, vertex infants from 2010 to 2015, who reached 10 cm cervical dilation. Multivariable logistic regression compared odds ratios for maternal and neonatal outcomes among women above and below the 90th, 95th, and 97th percentiles for first stage of labor duration. Receiver operating characteristic curves estimated the association between first stage of labor duration and maternal morbidity. Maternal morbidity was a composite of maternal fever, hemorrhage, transfusion, or endomyometritis; prolonged second stage of labor duration; and third- or fourth-degree perineal laceration. Neonatal morbidity was a composite of hypothermic therapy, need for mechanical ventilation, respiratory distress syndrome, meconium aspiration syndrome, birth injury or trauma, and neonatal seizure or sepsis.

RESULTS

Of 6823 women included in this study, 682 were anticipated to have first stage of labor duration above the 90th percentile cutoff point, which was associated with an increased risk of composite maternal morbidity, maternal fever, postpartum transfusion, prolonged second stage of labor duration, third- or fourth-degree perineal laceration, and cesarean or operative vaginal delivery (P≤.02) and an increased risk of composite neonatal morbidity, respiratory distress syndrome, need for mechanical ventilation, and neonatal sepsis (P≤.03). Composite maternal morbidity was 2.2 (95% confidence interval, 1.8-2.7), 1.9 (95% confidence interval, 1.4-2.4), and 1.8 (95% confidence interval, 1.3-2.5) times more likely to occur among women above the 90th, 95th, and 97th percentile, respectively, for first stage of labor duration from 4 to 10 cm. Composite neonatal morbidity was 2.6 (95% confidence interval, 2.1-3.2), 2.2 (95% confidence interval, 1.7-2.9), and 1.9 (95% confidence interval, 1.3-2.8) times more likely to occur among infants delivered by women above the 90th, 95th, and 97th percentiles for first stage of labor duration from 4 to 10 cm. Receiver operating characteristic curves among all women from 4 to 10 cm and 6 to 10 cm, including when stratified by parity and type of labor onset, had an area under the curve of 0.51 to 0.62 and 0.53 to 0.71 for maternal and neonatal morbidity, respectively. Thus, duration of labor has moderate predictive ability, at best, for composite maternal or neonatal morbidity. No curve demonstrated a clear point at which adverse maternal or neonatal outcomes increased that could be used to define abnormal labor.

CONCLUSION

The benefit of expectantly managing a prolonged first stage of labor with duration above the 90th percentile in anticipation of vaginal delivery must be weighed against the increased risk of composite maternal and neonatal morbidity. Risks associated with performing cesarean delivery as an alternative management for women with prolonged first stage of labor duration must also be considered.

Cervical dilation at the time of epidural catheter insertion is not associated with the degree of prolongation of the first or second stages of labor, or the rate of instrumental vaginal delivery

INTRODUCTION

Epidural analgesia (EA) is an established option for efficient intrapartum analgesia. Meta-analyses have shown that EA differentially affects the first stage of labor but prolongs the second. The question of EA timing remains open. We aimed to investigate whether EA prolongs delivery in total and whether the EA administration timing vis-à-vis cervical dilation at catheter insertion is associated with a modulation of its effects on the duration of the first and second stages, as well as the rate of instrumental vaginal delivery in primiparas and multiparas.

MATERIAL AND METHODS

A retrospective electronic medical records-based study of 18 870 singleton term deliveries occurring in our institution from 2003 to 2015. Cervical dilation was determined within a half-hour of EA administration. We examined whether cervical dilation at EA administration correlated with the duration of the first and/or second stage, with the rate of prolonged second stage, and with the rate of interventional delivery. The study group was stratified to 10 subgroups defined by 1-cm intervals of cervical dilation at EA administration. Logistic regression modeling was applied to analyze the association between EA timing and rate of instrumental delivery while controlling for possible confounders.

RESULTS

In primiparas, receiving EA correlated with longer medians of active first stage (+51 minutes; P < .001) and second stage (+55 minutes; P < .001). In multiparas, median increases in active first stage (+43 minutes; P < .001) and second stage (+8 minutes; P < .001) were noted. The timing of EA, vis-à-vis cervical dilation (1-10 cm) was not associated with a substantial modulation of these effects. Logistic regression showed that cervical dilation at EA was not associated with a higher instrumental vaginal delivery rate.

CONCLUSIONS

Epidural analgesia prolonged the first and second stages of labor vs no epidural. Having EA was associated with a higher instrumental delivery rate but not with higher rates of maternal or neonatal complications, in primi- and multiparas. Importantly, the timing of EA, vis-à-vis cervical dilation, was not associated with substantial changes in the duration of labor stages or the instrumental delivery rate. Thus, EA may be offered early in the first stage of labor.

Placental complications in subsequent pregnancies after prior cesarean section performed in the first versus second stage of labor

OBJECTIVE

To examine whether prior cesarean delivery (CD) in the first stage of labor (non-progressive labor in the first stage - NPL1), when compared with CD in the second stage of labor (non-progressive labor in the second stage - NPL2), is associated with different rates of third stage placental complications in the subsequent delivery.

METHODS

A retrospective cohort study, of all deliveries following a CD due to NLP1 or NLP2 that occurred between the years 1988 and 2013, was undertaken. Multiple gestation pregnancies, known uterine malformations or uterine fibroids were excluded. Rates of third stage complications (retained placenta, adherent/increta/percreta placenta, manual removal of the placenta) were compared between the groups. Univariate analysis was followed by multivariate analysis.

RESULTS

During the study period, there were 3828 subsequent deliveries of parturients who were operated due to NPL1 and NPL2 (72.91 and 27.09%, respectively). Rates of manual removal of the placenta as well as adherent placenta were significantly higher among parturients following CD due to NPL2 (28.4 versus 24.0%, p = .04, 1.2 versus 0.4% p < .01, respectively). In a multivariate analysis controlling for possible confounders, adherent placenta was found to be independently associated with vaginal delivery following CD due to NPL2 (odds ratio 2.98, 95% confidence interval 1.30-6.77).

CONCLUSIONS

Prior CD due to NPL2 as opposed to NPL1 is independently associated with adherent placenta in the subsequent delivery. A higher index of suspicion may be needed when evaluating these women during pregnancy as well as during management of the delivery.

The relationship between attitude toward labor pain and length of the first, second, and third stages in primigravida women

INTRODUCTION

Factors affecting labor pain include physiological, psychological, and social factors, among which psychological factors refer to attitudes and beliefs about labor pain. Hence, the present study was conducted to determine the relationship between attitude toward labor pain and length of the first, second, and third stages in primigravida women.

MATERIALS AND METHODS

This cross-sectional study was performed on 230 pregnant women who were referred to hospitals affiliated to Isfahan University of Medical Sciences in a two-stage sampling in 2018. In the beginning, the participants completed the questionnaire of demographic/fertility characteristics and attitude to labor pain (25Q), and at the next stage, the researcher completed the form of labor information including length of the labor stages. Data were analyzed by SPSS software version 22 and Pearson correlation coefficient, Student's t-test, one-way ANOVA, and general linear regression.

RESULTS

The mean (standard deviation) of the attitude to labor pain was 53.96 (1.9), and the length of the first stage was 10.01 (0.3) (h), the second stage was 1.6 (0.4) (h), and the third stage was 15.9 (1.7) (min). One hundred and eighty-three (79.6%) had negative attitude and 47 (20.4%) had positive attitude toward labor pain. There was a significant positive correlation between attitude toward labor pain and length of the first (P = 0.001, r = 0.37) and second stages of labor (P = 0.001, r = 0.24). There was no significant between length of third stage of labor and attitude toward labor pain (P = 714).

CONCLUSION

The results showed that the majority of primiparous women had a higher (negative) attitude toward labor pain, which was associated with longe the first and second stages of labor.

Healthy Birth Practice #2: Walk, Move Around, and Change Positions Throughout Labor

Women who use upright positions and are mobile during labor have shorter labors, less intervention, fewer cesarean births, and report less severe pain, and describe more satisfaction with their childbirth experience than women in recumbent positions. The evidence for supporting physiologic childbearing for optimal birth fails to disrupt intervention intensive hospital practices that deny 60% of women mobility in labor despite calls by maternity care organizations to not restrict mobility for low risk women in spontaneous labor.

Head progression distance during the first stage of labor as a predictor for delivery outcome

Objectives: To assess if measurement of the head progression distance (PD) during the first stage of labor in nulliparous women can predict the delivery method.Methods: A prospective study was conducted on consecutive nulliparous women beyond 37 week's gestation during the first stage of labor. Transperineal ultrasound was performed to assess the PD. Analysis was performed on the relationships between PD during rest and during voluntary pushing and the fetal and maternal characteristics, delivery mode, and immediate postnatal outcomes.Results: Eighty seven suitable nulliparous women were suitable for analysis. PD was found to be significantly longer in women who delivered vaginally (VD) compared to those who underwent a cesarean section (CS) for obstructed labor: PD at rest was 2.51 ± 1.71 cm in women who delivered vaginally compared to 1.48 ± 1.9 cm in women who delivered by CS (p = .01). The PD during pushing was 3.43 ± 1.8 cm for a VD compared to 1.5 ± 2.1 cm for CS (p = .015). Logistic regression and receiver-operating characteristics curve analysis demonstrated a moderate predictive value of PD with respect to the mode of delivery (area under the curve was 0.67 during both resting and pushing period).Conclusion: PD measurements during the first stage of labor among nulliparous women differ significantly both in rest and during pushing between patients who delivered vaginally compared to CS and can therefore assist in predicting the mode of delivery.

Cervical Dilatation Curves of Spontaneous Deliveries in Pregnant Japanese Females

Background: Although cervical dilatation curves are crucial for appropriate management of labor progression, abnormal labor progression and obstetric interventions were included in previous and widely-used cervical dilatation curves. We aimed to describe the cervical dilatation curves of normal labor progression in pregnant Japanese females without abnormal labor progression and obstetric interventions. Methods: We completed retrospective obstetric record reviews on 3172 pregnant Japanese females (parity = 0, n = 1047; parity = 1, n = 1083; parity ≥ 2, n = 1042), aged 20 to 39 years old at delivery, with pregravid body mass indices of less than 30. All patients underwent spontaneous deliveries with term, singleton, cephalic and live newborns of appropriate-for-gestational age birthweight, without adverse neonatal outcomes. We characterized labor progression patterns by examining the relationship between elapsed times from the full dilatation and cervical dilatation stages, and labor durations by examining the distribution of time intervals from one cervical dilatation stage, to the next, and ultimately to the full dilatation. Results: Fastest cervical changes occurred at 6 cm (primiparas) and 5 cm (multiparas) of dilatation. The 95%tile of labor progression took over 3 hours to progress from 6 cm to 7 cm (primiparas), and over 2 hours to progress from 5 cm to 6 cm (multiparas). The 5%tile of traverse time to the full dilatation, during the active phase, was less than 1 hour (primiparas) and 0.5 hours (multiparas). At the end of the active phase, no deceleration phase was observed. Conclusions: Active labor may not start until 5 cm of dilatation. At the beginning of the active phase, cervical dilatation was slower than previously described. These results may reduce opportunities for obstetric interventions during labor progression.

Impact factors on cervical dilation rates in the first stage of labor

AIMS

To assess cervical dilation rates of nulliparous and multiparous women in the active first stage of labor and to evaluate significant impact factors.

METHODS

In a retrospective cohort study between January 2007 and July 2014 at the University Hospital of Zurich in Switzerland, we analyzed 8378 women with singleton pregnancies in vertex presentation with a vaginal delivery at 34+0 to 42+5 gestational weeks. Median cervical dilation rates were calculated and different impact factors evaluated.

RESULTS

Cervical dilation rates increase during labor progress with faster rates in multiparous compared with nulliparous women (P<0.001). Dilation rates exceed 1 cm/h at a dilatation of 6-7 cm, but are very individual. Accelerating impact factors are multiparity, a greater amount of cervical dilation and fetal occipitoanterior position, whereas the use of epidural anesthesia, a higher fetal weight and head circumference decelerate dilation (P<0.001).

CONCLUSION

Cervical dilation is a hyperbolic increasing process, with faster dilation rates in multiparous compared to nulliparous women and a reversal point of labor around 6-7 cm, respectively. Besides, cervical dilation is highly individual and affected by several impact factors. The diagnosis of labor arrest or prolonged labor should therefore be based on such rates and on the individual evaluation of every woman.

The "occiput-spine angle": a new sonographic index of fetal head deflexion during the first stage of labor

BACKGROUND

Fetal head "attitude" (relationship of fetal head to spine) in the first stage of labor may have a substantial impact on labor outcome. The diagnosis of fetal head deflexion traditionally is based on digital examination in labor, although the use of ultrasound to support clinical diagnosis has been recently reported.

OBJECTIVES

The aims of this study were: (1) to quantify the degree of fetal head deflection via the use of sonography during the first stage of labor; and (2) to determine whether a parameter derived from ultrasound examination (the occiput-spine angle) has a relationship with the course and outcome of labor.

STUDY DESIGN

This was a prospective multicentric, cross-sectional study conducted at the Maternity Unit of the University of Bologna and Parma from January 2014 to April 2015. A nonconsecutive series of women with uncomplicated singleton pregnancies at term gestation (37 weeks or more) were submitted to transabdominal ultrasound during the first stage of labor. If fetal position was occiput anterior or transverse, the angle between the fetal occiput and the cervical spine (the occiput-spine angle) was sonographically obtained on the sagittal plane. The measurements of the occiput spine-angle were performed offline by 2 operators who were blinded to the labor outcome. The intra- and interobserver reproducibility and the correlation between the occiput-spine angle and the mode of delivery were evaluated.

RESULTS

A total of 108 pregnant women were recruited, 79 of which underwent a spontaneous vaginal delivery and 29 were submitted to obstetric intervention (19 cesarean delivery and 10 instrumental vaginal deliveries). The mean value of the occiput-spine angle measured in the active phase of the first stage was 126° ± 9.8° (SD). The occiput-spine angle measurement showed a very good intraobserver (r = 0.86; 95% confidence interval [95% CI] 0.80-0.90) and a fair-to-good interobserver (r = 0.64; 95% CI 0.51-0.74) agreement. The occiput-spine angle was significantly narrower in women who underwent obstetric intervention (cesarean or vacuum delivery) due to labor arrest (121° ± 10.5° vs 127° ± 9.4°, P = .03). Multivariable logistic regression analysis showed that narrow occiput-spine angle values (OR 1.08; 95% CI 1.00-1.16; P = .04) and nulliparity (OR 16.06; 95% CI 1.71-150.65; P = .02) were independent risk factors for operative delivery. A larger occiput-spine angle width (i.e., >125°) showed to be significantly associated with a shorter duration of labor (hazard ratio = 1.62; 95% CI 1.07-2.45; P = .02).

CONCLUSION

We described herein the "occiput-spine angle," a new sonographic parameter to assess fetal head deflection during labor. Fetuses with smaller occiput-spine angle (<125°) are at increased risk for operative delivery.

Assessing first-stage labor progression and its relationship to complications

BACKGROUND

New labor curves have challenged the traditional understanding of the general pattern of dilation and descent in labor. They also revealed wide variation in the time to advance in dilation. An interval of arrest such as 4 hours did not fall beyond normal limits until dilation had reached 6 cm. Thus, the American College of Obstetricians and Gynecologists/Society for Maternal-Fetal Medicine first-stage arrest criteria, based in part on these findings, are applicable only in late labor. The wide range of time to dilate is unavoidable because cervical dilation has neither a precise nor direct relationship to time. Newer statistical techniques (multifactorial models) can improve precision by incorporating several factors that are related directly to labor progress. At each examination, the calculations adapt to the mother's current labor conditions. They produce a quantitative assessment that is expressed in percentiles. Low percentiles indicate potentially problematic labor progression.

OBJECTIVE

The purpose of this study was to assess the relationship between first-stage labor progress- and labor-related complications with the use of 2 different assessment methods. The first method was based on arrest of dilation definitions. The other method used percentile rankings of dilation or station based on adaptive multifactorial models.

STUDY DESIGN

We included all 4703 cephalic-presenting, term, singleton births with electronic fetal monitoring and cord gases at 2 academic community referral hospitals in 2012 and 2013. We assessed electronic data for route of delivery, all dilation and station examinations, newborn infant status, electronic fetal monitoring tracings, and cord blood gases. The labor-related complication groups included 272 women with cesarean delivery for first-stage arrest, 558 with cesarean delivery for fetal heart rate concerns, 178 with obstetric hemorrhage, and 237 with neonatal depression, which left 3004 women in the spontaneous vaginal birth group. Receiver operating characteristic curves were constructed for each assessment method by measurement of the sensitivity for each complication vs the false-positive rate in the normal reference group.

RESULTS

The duration of arrest at ≥6 cm dilation showed poor levels of discrimination for the cesarean delivery interventions (area under the curve, 0.55-0.65; P < .01) and no significant relationship to hemorrhage or neonatal depression. The dilation and station percentiles showed high discrimination for the cesarean delivery-related outcomes (area under the curve, 0.78-0.93; P < .01) and low discrimination for the clinical outcomes of hemorrhage and neonatal depression (area under the curve, 0.58-0.61; P < .01).

CONCLUSIONS

Duration of arrest of dilation at ≥6 cm showed little or no discrimination for any of the complications. In comparison, percentile rankings that were based on the adaptive multifactorial models showed much higher discrimination for cesarean delivery interventions and better, but low discrimination for hemorrhage. Adaptive multifactorial models present a different method to assess labor progress. Rather than "pass/fail" criteria that are applicable only to dilation in late labor, they produce percentile rankings, assess 2 essential processes for vaginal birth (dilation and descent), and can be applied from 3 cm onward. Given the limitations of labor-progress assessment based solely on the passage of time and because of the extreme variation in decision-making for cesarean delivery for labor disorders, the types of mathematic analyses that are described in this article are logical and promising steps to help standardize labor assessment.

Descent of the fetal head (station) during the first stage of labor

BACKGROUND

High station at specific points in the first stage of labor, such as a floating head on admission, or at 4-cm dilation or when arrest of dilation occurs, is associated with higher rates of failure to deliver vaginally. Therefore it could be useful to know if station is within an expected range at a given dilation during first stage. Arrest of descent disorders have been defined thus far on criteria applicable in the second stage. Statistical modeling is an attractive methodology to characterize the relationship between station and dilation because the resulting mathematical expressions could be used as a reference for comparison in the future. In addition, they can be used to produce a finely graded assessment of descent using numerical terms such as percentile rankings. A 2-step approach to potentially improving the assessment of station could be to develop a statistical model that describes the general relationship between station and dilation in the first stage of uncomplicated births and then determine if such a model would have identified births with complications related to poor labor progress. Given the complex nature of labor data, especially the imprecision of dilation and station measurement, it is not immediately evident that such a model is identifiable or what its precision would be.

OBJECTIVE

We sought to characterize in mathematical terms the relationship of station to dilation during the first stage of labor for nulliparous and multiparous women with spontaneous vaginal births.

STUDY DESIGN

This retrospective cohort study included 28,121 exams from 5555 women with singleton cephalic presentations at ≥37 weeks' gestation with electronic fetal monitoring tracings, who delivered vaginally without instrumentation and had 5-minute Apgar scores >6 at 2 academic community referral hospitals in 2012 through 2013. Women with a previous cesarean birth were excluded. We used longitudinal statistical techniques suitable to biological data that were irregularly sampled with repeated measures over time.

RESULTS

A linear relationship was observed between station and dilation. For both nulliparous and multiparous women the final model was a linear regression with random effects for intercept and slope and a first-order autoregressive correlation structure. The 5th-95th range of station at any given dilation spanned about 3-4 cm.

CONCLUSION

Our results demonstrate a general trend of increasing descent of the presenting part as dilation advances during the first stage of labor in women who delivered vaginally without instrumentation. We propose that the mathematical expressions describing this relationship may be valuable in the assessment of first-stage labor progression.

Labor patterns in women attempting vaginal birth after cesarean with normal neonatal outcomes

OBJECTIVE

We sought to describe labor patterns in women with a trial of labor after cesarean (TOLAC) with normal neonatal outcomes.

STUDY DESIGN

In a retrospective observational study at 12 US centers (2002 through 2008), we examined time interval for each centimeter of cervical dilation and compared labor progression stratified by spontaneous or induced labor in 2892 multiparous women with TOLAC (second delivery) and 56,301 nulliparous women at 37 0/7 to 41 6/7 weeks of gestation. Analyses were performed including women with intrapartum cesarean delivery, and also limiting only to women who delivered vaginally.

RESULTS

Labor was induced in 23.4% of TOLAC and 44.1% of nulliparous women (P < .001). Cesarean delivery rates were 57.7% in TOLAC vs 19.0% in nulliparous women (P < .001). Oxytocin was used in 52.4% of TOLAC vs 64.3% of nulliparous women with spontaneous labor (P < .001) and 89.8% of TOLAC vs 91.6% of nulliparous women with induced labor (P = .099); however, TOLAC had lower maximum doses of oxytocin compared to nulliparous women: median (90th percentile): 6 (18) mU/min vs 12 (28) mU/min, respectively (P < .001). Median (95th percentile) labor duration for TOLAC vs nulliparous women with spontaneous labor from 4-10 cm was 0.9 (2.2) hours longer (P = .007). For women who entered labor spontaneously and achieved vaginal delivery, labor patterns for TOLAC were similar to nulliparous women. For induced labor, labor duration for TOLAC vs nulliparous women from 4-10 cm was 1.5 (4.6) hours longer (P < .001). For women who achieved vaginal delivery, labor patterns were slower for induced TOLAC compared to nulliparous women.

CONCLUSION

Labor duration for TOLAC was slower compared to nulliparous labor, particularly for induced labor. By improved understanding of the rates of progress at different points in labor, this new information on labor curves in women undergoing TOLAC, particularly for induction, should help physicians when managing labor.

Healthy birth practice #2: walk, move around, and change positions throughout labor

In the United States, obstetric care is intervention intensive, resulting in 1 in 3 women undergoing cesarean surgery wherein mobility is treated as an intervention rather than supporting the natural physiologic process for optimal birth. Women who use upright positions and are mobile during labor have shorter labors, receive less intervention, report less severe pain, and describe more satisfaction with their childbirth experience than women in recumbent positions. This article is an updated evidence-based review of the "Lamaze International Care Practices That Promote Normal Birth, Care Practice #2: Freedom of Movement Throughout Labor," published in The Journal of Perinatal Education, 16(3), 2007.

Defining an abnormal first stage of labor based on maternal and neonatal outcomes

OBJECTIVE

The objective of the study was to determine the threshold for defining abnormal labor that is associated with adverse maternal and neonatal outcomes.

STUDY DESIGN

This study consisted of a retrospective cohort of all consecutive women admitted at a gestation of 37.0 weeks or longer from 2004 to 2008 who reached the second stage of labor. The 90th, 95th, and 97th percentiles for progress in the first stage of labor were determined specific for parity and labor onset. Women with a first stage above and below each centile were compared. Maternal outcomes were cesarean delivery in the second stage, operative delivery, prolonged second stage, postpartum hemorrhage, and maternal fever. Neonatal outcomes were a composite of the following: admission to level 2 or 3 nursery, 5 minute Apgar less than 3, shoulder dystocia, arterial cord pH of less than 7.0, and a cord base excess of -12 or less.

RESULTS

Of the 5030 women, 4534 experienced first stage of less than the 90th percentile, 251 between the 90th and 94th percentiles, 102 between the 95th and 96th percentiles, and 143 at the 97th percentile or greater. Longer labors were associated with an increased risk of a prolonged second stage, maternal fever, the composite neonatal outcome, shoulder dystocia, and admission to a level 2 or 3 nursery (P < .01). Depending on the cutoff used, 29-30 cesarean deliveries would need to be performed to prevent 1 shoulder dystocia.

CONCLUSION

Although women who experience labor dystocia may ultimately deliver vaginally, a longer first stage of labor is associated with adverse maternal and neonatal outcomes, in particular shoulder dystocia. This risk must be balanced against the risks of cesarean delivery for labor arrest.

Effect of hyoscine butylbromide first stage of labour in multiparus women

BACKGROUND

Prolonged labor is one of the most important risk factors for perinatal compromise and, if caused by obstructed labor, it carries the risk of uterine rupture, postpartum hemorrhage (PPH), puerperal sepsis, and maternal death.

OBJECTIVE

To determine whether or not hyoscine butylbromide shortens the stages of labor, without an increase in maternal or neonatal complications.

METHOD

In single-blinded randomized clinical trial study, 188 multiparas women in active phase of labor who were admitted to Shahid Sadoughi Hospital from October 2006 to April 2007 in Yazd - Iran, were evaluated. They were divided hyoscine group (n = 94) received 20mg (1ml) of hyoscine and control group (n = 94) received 1 ml of normal saline was given as placebo, intravenously. The effects of hyoscine in shortening labor time; and neonatal Apgar score was compared.

RESULTS

Duration of the first (mean± SD: 186.8 ± 125.6 minutes vs. 260.4 ± 120.9 minutes, p= 0.00 1) and second stage of labor (mean± SD: 20.0 ± 8.1minutes vs. 25.8 ± 9.4 minutes, p= 0.03) was shorter in hyoscine group. Frequency of cesarean section and mean of neonatal Apgar score at minutes of one and 5 were not different in both groups. No serious adverse events were seen in the two groups.

CONCLUSION

Injection of hyoscine in active phase of labor can be effective in shortening of labor without any adverse effect on mother and fetus.