Cervical score and onset of spontaneous labor in prolonged pregnancy dated by second-trimester ultrasonic scan

The interval from expected day of delivery to spontaneous onset of labor was correlated with parity and cervical score in 103 women with uncomplicated prolonged pregnancy (greater than 294 days). All women had a routine ultrasonic scan in weeks 16-18 for the purpose of dating. The mean (+/- SD) modified Bishop score on entry to the study was 4.15 +/- 2.0 for nulliparas and 4.90 +/- 2.1 for multiparas. The duration beyond 294 days to spontaneous onset of labor varied little (mean 3.5-4.5 days) for nulliparas with scores greater than 2 and for multiparas regardless of score. Nulliparous women with a poor score (less than 3) had spontaneous onset of labor and delivery within a mean of 9.8 days. Half of the multiparas (50.0%) and 43.9% of the nulliparas gave birth within 3 days. About 90% of all women gave birth within 7 days. All but three had a vaginal delivery; the instrumental vaginal delivery rate was 16.3%. The results suggest that in postterm women dated with a second-trimester ultrasonic scan, the cervical scores are in general more favorable than previously reported in series not dated with early scans. The postterm group is also much smaller, and the time interval from entry into the postterm period to spontaneous onset of labor is shorter.     

Characteristics of second labor occurring 10 or more years after the first.

Labor characteristics in 89 women undergoing a second vaginal delivery 10-18 years after the first were compared retrospectively with those of 136 women with an interval of 1-4 years between their first and second vaginal deliveries and with those of 128 nulliparous women. The pelvic findings on admission, average length of stages 1 and 2 of labor, average cervical dilation per hour and rates of surgical intervention in relation to arrest disorders were similar in the two multiparous groups and significantly different from these parameters in the nulliparous group. Women with long intervals between their first and second vaginal deliveries should be managed in the same way as are other multiparas and not like nulliparas with respect to such issues as indications for oxytocin treatment, surgical intervention and use of conduction anesthesia.     

Cervical assessment in women with threatened preterm labor.

OBJECTIVE: The aim of the study was to examine the clinical value of cervical assessment by transvaginal ultrasonography in women with symptoms of preterm labor. METHODS: We prospectively evaluated 172 women with singleton pregnancies and symptoms of preterm labor. Seventy of them were nulliparas, while 102 were multiparas. Gestational age ranged between 24 and 34 wks. All women underwent cervical assessment with transvaginal ultrasonography and were given intravenous tocolytics. The only parameter evaluated was cervical length. Women with multiple pregnancies, gestational age <24 wks or >34 wks, cervical dilatation >2 cm, placenta praevia, premature rupture of membranes, or cervical cerclage were excluded from the study. The outcome measure was delivery before 34 wks gestation. RESULTS: The preterm delivery rate before 34 wks was 37%. The sensitivity and the specificity of a cervical length of less than 20 mm was 60 and 53.8% and 97.7 and 95.2% for nulliparas and multiparas, respectively. A cervical length <20 mm was also 93.7% predictive of preterm delivery in nulliparas and 87.5% in multiparas, while the corresponding numbers for its negative predictive value (NPV) were 81.4 and 76.9%, respectively. CONCLUSIONS: Cervical assessment in women with symptoms of preterm labor can distinguish those at high risk for preterm delivery. Cervical sonography can be a valuable adjunct to the clinical evaluation of these patients.     

Active-phase labor arrest: oxytocin augmentation for at least 4 hours

OBJECTIVE: To assess a labor-management protocol that mandated at least 4 hours of oxytocin augmentation before cesarean delivery for active-phase labor arrest. METHODS: We prospectively evaluated term gravidas in spontaneous labor with active-phase labor arrest (cervix at least 4 cm dilated and 1 cm or less of cervical progress in 2 hours). Exclusion criteria included nonvertex presentation, previous cesarean, multiple gestation, and a nonreassuring fetal heart rate tracing or chorioamnionitis at the time of labor arrest. After the diagnosis of active-phase arrest, oxytocin was initiated with an intent to achieve a sustained uterine contraction pattern of greater than 200 Montevideo units. Cesarean delivery was not performed for labor arrest until at least 4 hours of a sustained uterine contraction pattern of greater than 200 Montevideo units, or a minimum of 6 hours of oxytocin augmentation if this contraction pattern could not be achieved. RESULTS: Five hundred forty-two women were managed by the protocol, and 92% delivered vaginally. The subsequent vaginal delivery rate for parous women who had not progressed (1 cm of cervical dilation or less) despite 2 hours of oxytocin augmentation was 91%, and it was 74% for nulliparas. With no labor progress after 4 hours of oxytocin augmentation, the subsequent vaginal delivery rates were 88% for parous women and 56% for nulliparas. There were no severe maternal complications. One neonate had persistent fetal circulation and one had a positive blood culture, but both did well. CONCLUSION: Extending the minimum period of oxytocin augmentation for active-phase labor arrest from 2 to at least 4 hours was effective and safe.     

Membrane sweeping in conjunction with labor induction

OBJECTIVE: To determine whether cervical membrane sweeping (stripping) during induction of labor is beneficial.METHODS: We compared outcomes of labor after induction in pregnant women at term in a randomized trial. Women were assigned to having their membranes swept or not during induction. Outcome measures included duration of labor, maximum dose of oxytocin used, induction-labor interval, and mode of delivery.RESULTS: We recruited 130 nulliparas (64 sweep, 66 nonsweep) and 118 multiparas (60 sweep, 58 nonsweep). Among nulliparas who received intravaginal prostaglandin (PG) E(2) and oxytocin, those who had simultaneous sweeping had significantly shorter mean (+/- standard error of mean) induction-labor interval (13.6 +/- 1.4 versus 17.3 +/- 1.2 hours, P =.048), lower mean maximum dose of oxytocin (6.8 +/- 0.8 versus 10.35 +/- 1.1 mU/minute, P =.01), and increased normal delivery rates (vaginal delivery 83. 3% versus 58.2%, P =.01). Sweeping also had a favorable effect on nulliparas who received oxytocin alone (mean induction-labor interval 5.8 +/- 3.1 versus 11.2 +/- 3.6 hours, P =.04; mean maximum dose 8.8 +/- 1.3 versus 16.3 +/- 1.9 mU/min, P =.01). Those differences were limited to women with unfavorable cervices. There were no differences in any outcome measures in multiparous women. CONCLUSION: Sweeping of the membranes during induction of labor had a beneficial effect on labor and delivery, which appeared to be limited to nulliparas with unfavorable cervices who needed cervical priming with PGE(2).     

Augmentation of Labour — Mode of Delivery Related to Cervimetric Progress

This study was designed to investigate the possible benefits, in terms of obstetric and neonatal outcome, of a prolonged augmentation period with oxytocin in patients with dysfunctional first stage of labour. The majority of patients (65.5% of nulliparas and 83.8% of multiparas) responded with satisfactory progress within the first 4 hours of augmentation and the Caesarean section rate was low in this group (1.3%). In those with unsatisfactory progress during the first 4 hours of augmentation a further 4 hour period of augmentation resulted in vaginal delivery for 50.7% of nulliparas with primary dysfunctional labour and 33.3% of those with secondary arrest in labour. Corresponding figures for multiparas were 41.7% and 25.0%, respectively. The neonatal outcome was uniformly good. It is concluded that the management protocol presented for augmentation of labour seems to be a safe procedure and might reduce the rising Caesarean section rate for dystocia.     

Cervical assessment in women with threatened preterm labor

Objective.?The aim of the study was to examine the clinical value of cervical assessment by transvaginal ultrasonography in women with symptoms of preterm labor.

Methods.?We prospectively evaluated 172 women with singleton pregnancies and symptoms of preterm labor. Seventy of them were nulliparas, while 102 were multiparas. Gestational age ranged between 24 and 34 wks. All women underwent cervical assessment with transvaginal ultrasonography and were given intravenous tocolytics. The only parameter evaluated was cervical length. Women with multiple pregnancies, gestational age <?24 wks or >?34 wks, cervical dilatation >?2?cm, placenta praevia, premature rupture of membranes, or cervical cerclage were excluded from the study. The outcome measure was delivery before 34 wks gestation.

Results.?The preterm delivery rate before 34 wks was 37%. The sensitivity and the specificity of a cervical length of less than 20?mm was 60 and 53.8% and 97.7 and 95.2% for nulliparas and multiparas, respectively. A cervical length <?20?mm was also 93.7% predictive of preterm delivery in nulliparas and 87.5% in multiparas, while the corresponding numbers for its negative predictive value (NPV) were 81.4 and 76.9%, respectively.

Conclusions.?Cervical assessment in women with symptoms of preterm labor can distinguish those at high risk for preterm delivery. Cervical sonography can be a valuable adjunct to the clinical evaluation of these patients.     

Predictors of vaginal delivery in patients with a previous cesarean section, who require oxytocin

Prospective analysis of 98 consecutive patients at term pregnancy with one previous cesarean section, who received oxytocin during a trial of labor (34 inductions, 64 augmentations), was undertaken to identify specific factors associated with successful vaginal delivery. The overall vaginal delivery rate was 59.2%. Comparing route of delivery in the induction and augmentation groups separately revealed no significant differences in maternal height, weight, or parity, duration of membrane rupture, length of oxytocin treatment or maximum dose, cervical examination on admission or before oxytocin treatment, or use of conduction anesthesia. A previous vaginal delivery favored repeat vaginal delivery in patients with augmentation while a nonrecurrent indication was significantly associated with vaginal delivery in all patients. After the beginning of oxytocin augmentation, the cervical dilatation rate was 1.82 cm/hr in patients delivered vaginally, compared with 0.18 cm/hr in those requiring cesarean section (p less than 0.001). Any cervical dilatation during the first 2 hours of augmentation was associated with more frequent vaginal delivery: 24 of 40 vaginal deliveries (60%) versus six of 24 cesarean sections (25%, p less than 0.01). Discriminant analysis correctly identified route of delivery in 85.3% of those with induction and 87.5% of patients with augmentation. During a trial of labor, oxytocin induction or augmentation is effective in a majority of patients. Furthermore, an early response during augmentation is of predictive value when such patients are being managed.     

Transcutaneous electrical nerve stimulation (TENS) for adjuvant pain-relief during labor and delivery

Objective: We examined the efficacy of transcutaneous electrical nerve stimulation (TENS) in general and the new Freemom TENS device (LifeCare, Israel) in particular, for pain relief during labor and delivery. Methods: The study group consisted of 104 women. Forty-six nulliparas (44.2%) and 58 multiparas (55.8%), all of whom used the TENS device for pain relief during labor. All participants completed a questionnaire on the degree of pain relief afforded them by TENS during the delivery and related questions. The objective evaluation was based on the documented labor and delivery parameters including medical interventions during delivery. Results: The majority of subjects (72% of the nulliparas and 69% of the multiparas) considered TENS effective for the relief of pain during labor. Most of them (67% of the nulliparas and 60% of the multiparas) responded positively to the use of TENS in future deliveries. Sixty-five percent of the multiparas considered TENS at least as effective as the other pain relief methods they had used before. TENS significantly reduced the duration of the first stage of labor P<0.001 for nulliparas, P<0.005 for multiparas and it significantly decreased the amount of analgesics administered to individual patients. No significant difference was found in fetal heart rate tracings, Apgar scores and cord blood pH between the study group and an equal number of matched controls who used other forms of pain management. Conclusions: TENS is an effective non-pharmacological, non-invasive adjuvant pain relief modality for use in labor and delivery. TENS application reduced the duration of the first stage of labor and the amount of analgesic drug administered. There were no adverse effects on mothers or newborns.     

Uterine Activity in Spontaneous Labour with Breech Presentation

Uterine activity was quantified for patients who had a breech presentation, spontaneous labour and a vaginal delivery. Results were studied according to parity and in relation to cervical dilatation. The multiparas with breech presentation overall had lower uterine activity compared to nulliparas when the whole labour was considered. These values were compared with control patients with vertex presentation who had spontaneous normal labour and vaginal delivery. The median uterine activity values in breech presentation were not significantly different from control nulliparous or multiparous patients. Among the breech deliveries, irrespective of parity, mean Apgar scores at 1 and 5 minutes were over 6 and cord arterial blood pH values were above 7.15, but these results were significantly lower than the control cases with vertex presentation. The uterus performs similar uterine activity in spontaneous normal labour whether the fetus presents as a vertex or breech, when controlled for parity.     

Labor in the grand multipara

OBJECTIVE: To assess delivery time and the frequency of dystocia in grand multiparous (GMP) and grand grand multiparous (GGMP) women. METHOD: Labor records from 272 women with parity 4-8 (GMP) and 56 women with parity 9 or higher (GGMP) were retrospectively reviewed regarding duration of labor and the occurrence of dystocia. As a comparison, data from 263 women with parity 1-3 (LMP) and 87 nulliparas (NP) was used. RESULTS: Duration of labor, defined as time from admission of the laboring woman to delivery of the infant, lasted in median 2.0, 2.3 and 3.1 h in LMP, GMP and GGMP, respectively. There was no difference in mean cervical dilatation on admission in multiparous women. In GGMP, the presenting part was more frequently positioned above the pelvic inlet at time of admission. In multiparous women admitted during the latent phase, the active phase of labor lasted in median 3.7 h in GMP and 4.7 h in GGMP, significantly longer than 2.9 h in LMP. During the active phase of labor, GGMP experienced arrest of cervical dilatation more frequently than the LMP. In parous women, there was a positive relationship between parity and duration of the active phase of labor as well as the duration of labor. Infant's birth weight increased by parity. CONCLUSION: Duration of the active phase of labor increased after the fourth child. Failure of descent of the presenting part during the first stage of labor in addition to arrest of cervical dilatation was associated with a high cesarean section rate in the GMP woman.     

The influence of birth weight on labor in nulliparas

The purpose of this study was to examine the hypothesis that dystocia in nulliparas is directly related to birth weight. The study was confined to the first 1000 nulliparas delivered in 1988 who went into labor after 37 weeks' gestation with a single live fetus and cephalic presentation. The management of labor was standardized. As birth weight increased, there was an increase in the mean duration of labor and of the second stage of labor, in the incidence of oxytocin augmentation, and in the incidence of both cesarean and forceps delivery for dystocia. The direct relationship between birth weight and the mean duration of labor was independent of gestation and oxytocin augmentation. These findings suggest that birth weight is an important factor in the development of dystocia in nulliparas.     

Early versus delayed oxytocin augmentation in nulliparous women with prolonged labour—a randomised controlled trial

Objective  To study the effects of early versus delayed oxytocin augmentation on the obstetrical and neonatal outcome in nulliparous women with spontaneous but prolonged labour.
Design  Randomised controlled study.
Setting  Two delivery units in Sweden.
Population  Healthy nulliparous women with normal pregnancies, spontaneous onset of active labour, a cervical dilatation of 4–9 cm and no progress in cervical dilatation for 2 hours and for an additional hour if amniotomy was performed due to slow progress.
Methods  Women ( n = 630) were randomly allocated either to labour augmentation by oxytocin infusion (early oxytocin group) or to postponement of oxytocin augmentation for another 3 hours (expectant group).
Main outcome measure  Mode of delivery (spontaneous vaginal or instrumental vaginal delivery or caesarean section) and time from randomisation to delivery.
Results  The caesarean section rate was 29 of 314 (9%) in the early oxytocin group and 34 of 316 (11%) in the expectant group (OR 0.8, 95% CI 0.5–1.4), and instrumental vaginal delivery 54 of 314 (17%) in the early oxytocin versus 38 of 316 (12%) in the expectant group (OR 1.5, 95% CI 0.97–2.4). Early initiation of oxytocin resulted in a mean decrease of 85 minutes in the randomisation to delivery interval.
Conclusion  Early administration of oxytocin did not change the rate of caesarean section or instrumental vaginal delivery but shortened labour duration significantly in women with a 2-hour arrest in cervical dilatation. No other clear benefits or harms were seen between early and delayed administration of oxytocin.     

Singleton vaginal breech delivery at term: still a safe option

OBJECTIVE: To examine the obstetric and perinatal outcome of pregnancies with singleton breech presentation at term when selection for vaginal delivery was based on clear prelabor and intrapartum criteria. METHODS: The outcomes of all pregnancies with a breech presentation after 37 weeks of gestation were retrospectively reviewed from January 1997 to June 2000. Criteria for prelabor cesarean or trial of vaginal breech delivery included type of breech, estimated fetal weight (more than 3,800 g), maternal preference, and gestation more than 41 weeks. An intrapartum protocol excluded induction and oxytocin augmentation of labor, combined with a low threshold for cesarean delivery for dystocic labor; an experienced obstetrician was in attendance during labor and delivery. RESULTS: Of 641 women, 343 (54%) underwent prelabor cesarean, and 298 (46%) had a trial of vaginal delivery, of whom 146 (49%) delivered vaginally. Significantly fewer nulliparas (58 of 158, 37%) than multiparas (88 of 140, 63%; P <.001) achieved vaginal delivery after trial of labor. Significantly more infants weighing more than 3,800 g were selected for prelabor (87 of 343, 25%) and intrapartum (31 of 152, 20%) cesarean than delivered vaginally (15 of 146, 10%). Two neonates (0.7%) had Apgar scores of less than 7 at 5 minutes; both were neurologically normal at 6 weeks. There were no nonanomalous perinatal deaths and no cases of significant trauma or neurological dysfunction; 3 infants delivered vaginally died due to lethal anomalies. CONCLUSION: Safe vaginal breech delivery at term can be achieved with strict selection criteria, adherence to a careful intrapartum protocol, and with an experienced obstetrician in attendance. Our protocol effectively selects larger infants for cesarean delivery. LEVEL OF EVIDENCE: II-2     

Three-dimensional ultrasound power Doppler assessment of the cervix: comparison between nulliparas and multiparas

AIM: To assess the sonographic cervical characteristics between nulliparous and multiparous women. SUBJECT AND METHODS: Transvaginal three-dimensional ultrasound and power Doppler using the virtual organ computer-aided analysis (VOCAL) program were performed on 71 nulliparas and 59 multiparas at a mean gestational age of 25.3+/-7.9 weeks. We compared the cervical volume and power Doppler vascularization index (VI), flow index (FI), and vascularization-flow index (VFI) between nulliparas and multiparas. RESULTS: The mean cervical volume and mean VI, VFI, FI measurements were not significantly different between multiparas and nulliparas. CONCLUSION: Our observations suggest that the morphological changes in the cervix of parous women are merely configurational without a change in cervical mass and vascularization. These configurational changes might result from the inevitable cervical stretching during labor and represent a healing process that does not involve a subsequent change in mass or vascularity.     

Foley catheter with simultaneous oxytocin on labor induction: a meta-analysis of randomized controlled trials

Objective: It is unclear that whether Foley catheter with simultaneous oxytocin could improve the efficacy of induction outcome.

Method: To conduct a meta-analysis of randomized controlled trial (RCT) studies to evaluate the effect of Foley catheter with simultaneous oxytocin on labor induction. PubMed, Embase, and other databases were searched from their inception to July 2017. We included all RCTs comparing Foley catheter with simultaneous oxytocin (i.e. intervention group) with Foley catheter followed by oxytocin (i.e. control group) in the three kinds of women (nulliparas and multiparas/only nulliparas/only multiparas). We estimate summarized relative risk (RR) and 95% confidence intervals (CIs) for dichotomous outcomes, standard mean difference for continuous outcomes. Fixed- and random-effects models were used, depending on heterogeneity.

Results: After application of our inclusion and exclusion criteria, six RCTs with a total of 1133 participants were identified. We found that only nulliparas had significant RR of delivery within 24?h (RR?=?1.32, 95% CI: 1.12, 1.55, I²?=?46.5%). Meanwhile, there was no statistically significant difference between intervention and control groups in vaginal delivery in 24?h, cesarean delivery, time to delivery, and Apgar score at 5?min less than 7. Foley catheter with simultaneous oxytocin did not increase the risk of side effects, included chorioamnionitis, postpartum hemorrhage, uterine hyperstimulation, and neonatal intensive care unit admission.

Conclusion: The results seem to support the use of oxytocin to a Foley catheter at the initiation of labor induction, as it might lead to increases the rate of delivery within 24?h in nulliparas.     

Cervical dilatation at the time of cesarean section may affect the success of a subsequent vaginal delivery

Objective.?To evaluate the effect of labor progress prior to cesarean delivery on the outcome of vaginal birth after cesarean delivery (VBAC).

Methods. The medical records of women attempting VBAC between January 2000 and February 2008 were reviewed. All women had only one previous cesarean and underwent spontaneous labor.

Results.?Among 1148 enrolled women, 956 (83.3%) achieved a successful VBAC. Birth weight, previous indication for cesarean delivery and oxytocin augmentation were significantly associated with VBAC outcome. By multivariate analysis, a cervical dilatation ≥8 cm at previous cesarean was independently predictive of successful VBAC in women with a previous cesarean for non-recurrent indications (p = 0.046), yielding a VBAC success rate of 93.1%, whereas the extent of cervical dilatation at the previous cesarean did not affect the outcome of subsequent delivery in women with a previous cesarean for recurrent indications.

Conclusions.?Women with cesarean for non-recurrent indications who achieved a cervical dilatation ≥8 cm may be the best candidates for VBAC, with the greatest likelihood of a successful VBAC. Labor progress at previous cesarean can serve as a valuable indicator for VBAC outcome in women with a previous cesarean for non-recurrent indications, and therefore should be discussed as part of preconception counseling.     

Duration of labor. An analysis of influencing factors

9703 labors at Akershus Central Hospital during the period January 1979 to January 1984 were analysed to see which factors influenced the duration of labor. Median duration was 8.2 h for nulliparas, 5.3 h for multiparas. Parity greater than one had no influence on duration. Induced labors were 1.9 h (nulliparas) and 1.4 h (multiparas) shorter than those with spontaneous onset. Stepwise linear regression showed that duration of labor was positively correlated with the weight of the infant, duration of pregnancy, weight gain and prepregnant weight. It was negatively correlated with mother's height. Mother's age did not influence duration of labor. Occiput posterior presentation and extensions of the head prolonged labor in nulliparas, but not in multiparas, while breech presentation had no influence.     

Outcome in obstetric care related to oxytocin use. A population-based study

BACKGROUND: The purpose of this study was to investigate the delivery outcome in relation to oxytocin use in labor. METHODS: We studied 106,755 deliveries from 1995 to 2002 in the Perinatal Revision South, a population-based register comprising information from 10 hospitals in southern Sweden. RESULTS: Oxytocin use in labor increased from 27.6% in 1995/96 to 33.2% in 2001/02 (p<0.000006). Oxytocin was administered to 47.7% of the nulliparas and 18.5% of the multiparas. There were large differences between hospitals (range among nulliparas: 32.6-60.4%; among multiparas: 13.9-27.0%). After exclusion of deliveries with induction of labor and deliveries lasting >12 h, there was a significant association between oxytocin use and Apgar score < 7 at 5 min (OR 2.3; 95% CI 1.8-2.9), need for neonatal intensive care (OR 1.6; 95% CI 1.5-1.7), and operative delivery (OR 4.0; 95% CI 3.7-4.2). CONCLUSIONS: In deliveries with relatively short duration (< or =12 h), a significant association was seen between oxytocin use and adverse outcome. Even though the results are difficult to interpret, the significant difference between the use of oxytocin in different hospitals, as well as the increase of oxytocin use over time, calls for a randomized controlled study to elucidate the advantages and disadvantages of oxytocin use during labor and delivery.