Prostaglandins in biofluids in pregnancy and labour: A systematic review.

Prostaglandins are thought to be important mediators in the initiation of human labour, however the evidence supporting this is not entirely clear. Determining how, and which, prostaglandins change during pregnancy and labour may provide insight into mechanisms governing labour initiation and the potential to predict timing of labour onset. The current study systematically searched the existing scientific literature to determine how biofluid levels of prostaglandins change throughout pregnancy before and during labour, and whether prostaglandins and/or their metabolites may be useful for prediction of labour. The databases EMBASE and MEDLINE were searched for English-language articles on prostaglandins measured in plasma, serum, amniotic fluid, or urine during pregnancy and/or spontaneous labour. Studies were assessed for quality and risk of bias and a qualitative summary of included studies was generated. Our review identified 83 studies published between 1968-2021 that met the inclusion criteria. As measured in amniotic fluid, levels of PGE2, along with PGF2α and its metabolite 13,14-dihydro-15-keto-PGF2α were reported higher in labour compared to non-labour. In blood, only 13,14-dihydro-15-keto-PGF2α was reported higher in labour. Additionally, PGF2α, PGF1α, and PGE2 were reported to increase in amniotic fluid as pregnancy progressed, though this pattern was not consistent in plasma. Overall, the evidence supporting changes in prostaglandin levels in these biofluids remains unclear. An important limitation is the lack of data on the complexity of the prostaglandin pathway outside of the PGE and PGF families. Future studies using new methodologies capable of co-assessing multiple prostaglandins and metabolites, in large, well-defined populations, will help provide more insight as to the identification of exactly which prostaglandins and/or metabolites consistently change with labour. Revisiting and revising our understanding of the prostaglandins may provide better targets for clinical monitoring of pregnancies. This study was supported by the Canadian Institutes of Health Research.

Cytokines and pregnancy: Potential regulation by histone deacetylases.

Cytokines are important regulators of pregnancy and parturition. Aberrant expression of proinflammatory cytokines during pregnancy contributes towards preterm labor, pre-eclampsia, and gestational diabetes mellitus. The regulation of cytokine expression in human cells is highly complex, involving interactions between environment, transcription factors, and feedback mechanisms. Recent developments in epigenetic research have made tremendous advancements in exploring histone modifications as a key epigenetic regulator of cytokine expression and the effect of their signaling molecules on various organ systems in the human body. Histone acetylation and subsequent deacetylation by histone deacetylases (HDACs) are major epigenetic regulators of protein expression in the human body. The expression of various proinflammatory cytokines, their role in normal and abnormal pregnancy, and their epigenetic regulation via HDACs will be discussed in this review.

Fetal head progression and regression on maternal pushing at term and labor outcome.

OBJECTIVES: The aim of our study was two-fold. First, to evaluate the association between the change in the angle of progression (AoP) on maternal pushing and labor outcome. Second, to assess the incidence and clinical significance of the reduction of AoP on maternal pushing. METHODS: This was a prospective cohort study of nulliparous women with singleton pregnancy at term. AoP was measured at rest and on maximum Valsalva maneuver before the onset of labor, and the difference between AoP on maximum Valsalva and that at rest (ΔAoP) was calculated for each woman. Following delivery and data collection, we assessed the association between ΔAoP and various labor outcomes, including Cesarean section (CS), duration of the first, second and active second stages of labor, Apgar score and admission to the neonatal intensive care unit (NICU). The prevalence of women with reduction of AoP on maximum Valsalva maneuver (AoP-regression group) was calculated and its association with the mode of delivery and duration of different stages of labor was assessed. RESULTS: Overall, 469 women were included in the analysis. Among these, 273 (58.2%) had spontaneous vaginal birth, 65 (13.9%) had instrumental delivery and 131 (27.9%) underwent CS. Women in the CS group were older, had narrower AoP at rest and on maximum Valsalva, higher rate of epidural administration and lower 1-min and 5-min Apgar scores in comparison with the vaginal-delivery group. ΔAoP was comparable between the two groups. On Pearson's correlation analysis, AoP at rest and on maximum Valsalva maneuver had a significant negative correlation with the duration of the first stage of labor. ΔAoP showed a significant negative correlation with the duration of the active second stage of labor (Pearson's r, -0.125; P = 0.02). Cox regression model analysis showed that ΔAoP was associated independently with the duration of the active second stage (hazard ratio, 1.014 (95% CI, 1.003-1.025); P = 0.012) after adjusting for maternal age and body mass index. AoP reduction on maximum Valsalva was found in 73 (15.6%) women. In comparison with women who showed no change or an increase in AoP on maximum Valsalva, the AoP-regression group did not demonstrate significant difference in maternal characteristics, mode of delivery, rate of epidural analgesia, duration of the different stages of labor or rate of NICU admission. CONCLUSIONS: In nulliparous women at term before the onset of labor, narrower AoP at rest and on maximum Valsalva, reflecting fetal head engagement, is associated with a higher risk of Cesarean delivery. The increase in AoP from rest to Valsalva, reflecting more efficient maternal pushing, is associated with a shorter active second stage of labor. Fetal head regression on maternal pushing is present in about 16% of women and does not appear to have clinical significance. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.

The Golden Hours of Fetal Heart Rate Monitoring: Systematic Approach to the Critical Times of Labor and Delivery.

The first hour after admission and the last hour before delivery are critical times for identifying and preventing hypoxic-ischemic encephalopathy. These are times of transition that require coordinated steps to identify fetuses at risk, institute effective plans for fetal heart rate monitoring, and to establish situational awareness. Interpretation and intervention based on fetal heart rate monitoring is an important part of the care provided during these crucial times. We present checklists for the first and last hour of labor for use on labor and delivery to help standardize and optimize the approach to care during these times.

The initiation of labour at term gestation: Physiology and practice implications.

Little is known about the physiology of labour onset at term, and there is a debate about what signs and symptoms should be used to define it. In low resource settings, particularly for remote and rural communities, delay in recognising labour onset may mean a delay in seeking a skilled birth attendant. This chapter presents the most recent evidence about the physiology of labour onset, including the complex neuro-hormonal, biophysical, psychological and emotional factors that contribute. The symptoms of labour onset are explored from the perspective of both pregnant women and service providers in a range of sociocultural contexts. Early labour presents challenges for pregnant women, their families, communities and health care professionals. The chapter discusses how maternity care services should be designed, and delivered to ensure that women get the optimum advice and care at the beginning of labour.

Intrauterine Foley catheter for 48 versus 24 hours for cervical ripening: A randomized controlled trial.

OBJECTIVE: To compare the safety of keeping an intrauterine Foley catheter for 48 hours versus 24 hours for cervical ripening. METHODS: A randomized controlled trial was conducted at the De Soysa Hospital for Women, Sri Lanka from April 1 to December 31, 2014 (trial registration: SLCTR/2014/006). Low-risk women with a Bishop score ≤5 at 40 weeks + 5 days of gestation were allocated to either 24-hour (n=107; Group A) or 48-hour (n=94; Group B) groups. Proportions developing spontaneous onset of labor (SOL), neonatal status, pre- and post-procedure C-reactive protein (CRP), cervical smears, and placental histology in those who experienced SOL were compared. RESULTS: In Group A, 35 (32.7%) experienced SOL, against 54 (57.4%) in Group B (P<0.001, odds ratio 2.78, 95% confidence interval 1.56-4.93). There was no difference in mean length of active labor (7.48 vs 7.69 hours), cesarean delivery (16% vs 14%), bacterial vaginosis rates in post-induction cervical smear (10.3% vs 6.7%), mean CRP increase (4.08 vs 3.91 IU), evidence of chorioamnionitis (5.7% vs 11.1%), mean 1 and 5-minute Apgars, number of neonates with pyrexia (8.4 vs 8.5%), and admission to the Special Care Baby Unit (15% vs 12.8%). CONCLUSION: Group B experienced a statistically significant increase in SOL, without increasing infectious and neonatal morbidity.

An Assessment of the Effects of Hydrotherapy During the Active Phase of Labor on the Labor Process and Parenting Behavior.

This study was conducted to assess the effect on labor process and parenting behavior of hydrotherapy applied during the active phase of labor. This quasi-experimental study was conducted by using an equivalent comparison group (n = 40). The participants in the experimental group whose cervical dilation was 5 cm were taken to the hydrotherapy tub. This application continued until cervical dilation reached 10 cm. The Participants Questionnaire, The Birth Follow-up Questionnaire, The Postpartum ]collection tools. The duration of the active phase and second stage of labor was extremely short in the experimental group in comparison with the equivalent comparison group (p = .001). The Visual Analogue Scale (VAS) scores of the experimental group were lower than those of the equivalent comparison group when cervical dilation was 6 cm and 10 cm (p = .001). The experimental group also displayed more positive parenting behavior and positive labor feeling (p = .001).

Neonatal outcome in preterm deliveries before 34-week gestation - the influence of the mechanism of labor onset.

Purpose: To evaluate neonatal outcomes in preterm infants with less than 34 weeks after spontaneous labor, preterm premature rupture of membranes (PPROM) or iatrogenic delivery and to clarify whether the mechanism of labor onset is a risk factor for adverse short-term neonatal outcome. Methods: We performed a retrospective case-control study, which included 266 preterm newborns with less than 34-week gestation, between 2011 and 2015. Neonatal outcomes were compared according to the mechanism of labor onset. Our primary outcomes were neonatal death, sequelae on hospital discharge and a composite of these two variables (combined neonatal outcome). Results: Compared to spontaneous preterm labor, iatrogenic preterm newborns were at increased risk of respiratory distress syndrome (RDS) [Odds Ratio (OR) 3.05 (95%CI 1.31; 7.12)], and need of exogenous surfactant administration [OR 3.87 (95%CI 1.60; 9.35)]. PPROM was associated with higher risk of neonatal sepsis [OR 12.96 (95%CI 1.18; 142.67)]. There were no differences regarding the combined outcome for iatrogenic [OR 0.94 (95%CI 0.33; 2.71)] or PPROM [OR 1.11 (95%CI 0.35; 3.49)] groups. Conclusions: In our study, the different mechanisms of labor onset are associated with different neonatal outcomes. Iatrogenic preterm birth was associated with an increased risk of RDS and a higher need of exogenous surfactant administration than spontaneous group. The rate of neonatal sepsis was significantly higher in PPROM group along with a higher prevalence of histological chorioamnionitis.

Admission cardiotocography versus intermittent auscultation of the fetal heart in low-risk pregnancy during evaluation for possible labour admission - a multicentre randomised trial: the ADCAR trial.

OBJECTIVE: To assess the effect of admission cardiotocography (ACTG) versus intermittent auscultation (IA) of the fetal heart (FH) in low-risk pregnancy during assessment for possible labour on caesarean section rates. DESIGN: A parallel multicentre randomised trial. SETTING: Three maternity units in the Republic of Ireland. POPULATION: Healthy, low-risk pregnant women, at term and ≥ 18 years old, who provided written informed consent. METHODS: Women were randomised to receive IA of the FH or 20 minutes ACTG on admission for possible labour onset, using remote telephone randomisation. Both groups received IA during labour, with conversion to continuous CTG as clinically indicated. MAIN OUTCOME MEASURES: Caesarean section (primary outcome), obstetric interventions (e.g. continuous CTG during labour, fetal blood sampling, augmentation of labour) and neonatal morbidity (e.g. metabolic acidosis, admission to the neonatal intensive care unit, neonatal death). RESULTS: Based on 3034 women (1513 and 1521 randomised to IA and ACTG, respectively), there was no statistical difference between the groups in caesarean section [130 (8.6%) and 105 (6.9%) for IA and ACTG groups, respectively; relative risk (RR) 1.24; 95% CI 0.97-1.58], or in any other outcome except for use of continuous CTG during labour, which was lower in the IA group (RR 0.90, 95% CI 0.86-0.93). CONCLUSION: Our study demonstrates no differences in obstetric or neonatal outcomes between IA and ACTG for women with possible labour onset, other than an increased risk for continuous CTG in women receiving ACTG. TWEETABLE ABSTRACT: No differences in outcomes between intermittent auscultation and admission cardiotocography for women with possible labour onset.

Timing of singleton births by onset of labour and mode of birth in NHS maternity units in England, 2005-2014: A study of linked birth registration, birth notification, and hospital episode data.

BACKGROUND: Maternity care has to be available 24 hours a day, seven days a week. It is known that obstetric intervention can influence the time of birth, but no previous analysis at a national level in England has yet investigated in detail the ways in which the day and time of birth varies by onset of labour and mode of giving birth. METHOD: We linked data from birth registration, birth notification, and Maternity Hospital Episode Statistics and analysed 5,093,615 singleton births in NHS maternity units in England from 2005 to 2014. We used descriptive statistics and negative binomial regression models with harmonic terms to establish how patterns of timing of birth vary by onset of labour, mode of giving birth and gestational age. RESULTS: The timing of birth by time of day and day of the week varies considerably by onset of labour and mode of birth. Spontaneous births after spontaneous onset are more likely to occur between midnight and 6am than at other times of day, and are also slightly more likely on weekdays than at weekends and on public holidays. Elective caesarean births are concentrated onto weekday mornings. Births after induced labours are more likely to occur at hours around midnight on Tuesdays to Saturdays and on days before a public holiday period, than on Sundays, Mondays and during or just after a public holiday. CONCLUSION: The timing of births varies by onset of labour and mode of birth and these patterns have implications for midwifery and medical staffing. Further research is needed to understand the processes behind these findings.

Massage, reflexology and other manual methods for pain management in labour.

BACKGROUND: Many women would like to avoid pharmacological or invasive methods of pain management in labour, and this may contribute towards the popularity of complementary methods of pain management. This review examined the evidence currently available on manual methods, including massage and reflexology, for pain management in labour. This review is an update of the review first published in 2012. OBJECTIVES: To assess the effect, safety and acceptability of massage, reflexology and other manual methods to manage pain in labour. SEARCH METHODS: For this update, we searched Cochrane Pregnancy and Childbirth's Trials Register (30 June 2017), the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 6), MEDLINE (1966 to 30 June 2017, CINAHL (1980 to 30 June 2017), the Australian New Zealand Clinical Trials Registry (4 August 2017), Chinese Clinical Trial Registry (4 August 2017), ClinicalTrials.gov, (4 August 2017), the National Center for Complementary and Integrative Health (4 August 2017), the WHO International Clinical Trials Registry Platform (ICTRP) (4 August 2017) and reference lists of retrieved trials. SELECTION CRITERIA: We included randomised controlled trials comparing manual methods with standard care, other non-pharmacological forms of pain management in labour, no treatment or placebo. We searched for trials of the following modalities: massage, warm packs, thermal manual methods, reflexology, chiropractic, osteopathy, musculo-skeletal manipulation, deep tissue massage, neuro-muscular therapy, shiatsu, tuina, trigger point therapy, myotherapy and zero balancing. We excluded trials for pain management relating to hypnosis, aromatherapy, acupuncture and acupressure; these are included in other Cochrane reviews. DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trial quality, extracted data and checked data for accuracy. We contacted trial authors for additional information. We assessed the quality of the evidence using the GRADE approach. MAIN RESULTS: We included a total of 14 trials; 10 of these (1055 women) contributed data to meta-analysis. Four trials, involving 274 women, met our inclusion criteria but did not contribute data to the review. Over half the trials had a low risk of bias for random sequence generation and attrition bias. The majority of trials had a high risk of performance bias and detection bias, and an unclear risk of reporting bias. We found no trials examining the effectiveness of reflexology.MassageWe found low-quality evidence that massage provided a greater reduction in pain intensity (measured using self-reported pain scales) than usual care during the first stage of labour (standardised mean difference (SMD) -0.81, 95% confidence interval (CI) -1.06 to -0.56, six trials, 362 women). Two trials reported on pain intensity during the second and third stages of labour, and there was evidence of a reduction in pain scores in favour of massage (SMD -0.98, 95% CI -2.23 to 0.26, 124 women; and SMD -1.03, 95% CI -2.17 to 0.11, 122 women). There was very low-quality evidence showing no clear benefit of massage over usual care for the length of labour (in minutes) (mean difference (MD) 20.64, 95% CI -58.24 to 99.52, six trials, 514 women), and pharmacological pain relief (average risk ratio (RR) 0.81, 95% CI 0.37 to 1.74, four trials, 105 women). There was very low-quality evidence showing no clear benefit of massage for assisted vaginal birth (average RR 0.71, 95% CI 0.44 to 1.13, four trials, 368 women) and caesarean section (RR 0.75, 95% CI 0.51 to 1.09, six trials, 514 women). One trial reported less anxiety during the first stage of labour for women receiving massage (MD -16.27, 95% CI -27.03 to -5.51, 60 women). One trial found an increased sense of control from massage (MD 14.05, 95% CI 3.77 to 24.33, 124 women, low-quality evidence). Two trials examining satisfaction with the childbirth experience reported data on different scales; both found more satisfaction with massage, although the evidence was low quality in one study and very low in the other.Warm packsWe found very low-quality evidence for reduced pain (Visual Analogue Scale/VAS) in the first stage of labour (SMD -0.59, 95% CI -1.18 to -0.00, three trials, 191 women), and the second stage of labour (SMD -1.49, 95% CI -2.85 to -0.13, two trials, 128 women). Very low-quality evidence showed reduced length of labour (minutes) in the warm-pack group (MD -66.15, 95% CI -91.83 to -40.47; two trials; 128 women).Thermal manual methodsOne trial evaluated thermal manual methods versus usual care and found very low-quality evidence of reduced pain intensity during the first phase of labour for women receiving thermal methods (MD -1.44, 95% CI -2.24 to -0.65, one trial, 96 women). There was a reduction in the length of labour (minutes) (MD -78.24, 95% CI -118.75 to -37.73, one trial, 96 women, very low-quality evidence). There was no clear difference for assisted vaginal birth (very low-quality evidence). Results were similar for cold packs versus usual care, and intermittent hot and cold packs versus usual care, for pain intensity, length of labour and assisted vaginal birth.Music One trial that compared manual methods with music found very low-quality evidence of reduced pain intensity during labour in the massage group (RR 0.40, 95% CI 0.18 to 0.89, 101 women). There was no evidence of benefit for reduced use of pharmacological pain relief (RR 0.41, 95% CI 0.16 to 1.08, very low-quality evidence).Of the seven outcomes we assessed using GRADE, only pain intensity was reported in all comparisons. Satisfaction with the childbirth experience, sense of control, and caesarean section were rarely reported in any of the comparisons. AUTHORS' CONCLUSIONS: Massage, warm pack and thermal manual methods may have a role in reducing pain, reducing length of labour and improving women's sense of control and emotional experience of labour, although the quality of evidence varies from low to very low and few trials reported on the key GRADE outcomes. Few trials reported on safety as an outcome. There is a need for further research to address these outcomes and to examine the effectiveness and efficacy of these manual methods for pain management.

A comparison of enriched culture and Xpert polymerase chain reaction assay of Group B streptococcus carrier status at 35-37-week gestation to labor onset: a prospective controlled study.

OBJECTIVES: (1) To compare the accuracy of vagino-rectal enriched culture (EC) and a rapid polymerase chain reaction (PCR) test for the detection of Group B streptococcus (GBS) carrier status at 35-37-week gestation and at onset of labor. (2) To assess the conversion rate of GBS carrier status between 35-37 weeks to the onset of labor according to the EC/PCR tests. A prospective study was performed at a women's health clinic, referred to give birth at one medical center. STUDY POPULATION: Low risk pregnant women at 35-37-week gestation who did not know their GBS carrier status. METHODS: Participants were evaluated for GBS status both at 35-37 weeks and at labor onset. Correlation between tests was calculated by Spearman correlation. RESULTS: One hundred and ten specimens were analyzed. Correlations: EC-PCR: 35-37 weeks - very high (r = 0.8), at labor - high (r = 0.5). EC-EC: 35-37 weeks and at labor - high (r = 0.39); PCR-PCR: 35-37 weeks and at labor- high (r = 0.7). CONCLUSIONS: Both the EC and Xpert PCR tests are accurate for detecting GBS carrier, both at 35-37 weeks and at labor onset. We did not detect a significant conversion of the GBS status from negative at 35-37 weeks to positive at onset of labor.

Likelihood of cesarean delivery after applying leading active labor diagnostic guidelines.

BACKGROUND: Friedman, the United Kingdom's National Institute for Health and Care Excellence (NICE), and the American College of Obstetricians and Gynecologists/Society for Maternal-Fetal Medicine (ACOG/SMFM) support different active labor diagnostic guidelines. Our aims were to compare likelihoods for cesarean delivery among women admitted before vs in active labor by diagnostic guideline (within-guideline comparisons) and between women admitted in active labor per one or more of the guidelines (between-guideline comparisons). DESIGN: Active labor diagnostic guidelines were retrospectively applied to cervical examination data from nulliparous women with spontaneous labor onset (n = 2573). Generalized linear models were used to determine outcome likelihoods within- and between-guideline groups. RESULTS: At admission, 15.7%, 48.3%, and 10.1% of nulliparous women were in active labor per Friedman, NICE, and ACOG/SMFM diagnostic guidelines, respectively. Cesarean delivery was more likely among women admitted before vs in active labor per the Friedman (AOR 1.75 [95% CI 1.08-2.82] or NICE guideline (AOR 2.55 [95% CI 1.84-3.53]). Between guidelines, cesarean delivery was less likely among women admitted in active labor per the NICE guideline, as compared with the ACOG/SMFM guideline (AOR 0.55 [95% CI 0.35-0.88]). CONCLUSION: Many nulliparous women are admitted to the hospital before active labor onset. These women are significantly more likely to have a cesarean delivery. Diagnosing active labor before admission or before intervention to speed labor may be one component of a multi-faceted approach to decreasing the primary cesarean rate in the United States. The NICE diagnostic guideline is more inclusive than Friedman or ACOG/SMFM guidelines and its use may be the most clinically useful for safely lowering cesarean rates.

Cervical dilation at time of caesarean delivery in nulliparous women: a population-based cohort study.

OBJECTIVES: Our objective was to describe contemporary practice patterns in the timing of caesarean delivery in relation to cervical dilation, overall and by indication for caesarean. Our secondary objective was to examine how commonly caesarean delivery was performed for labour dystocia at dilations below 4 cm or without the use of oxytocin, overall and between hospitals. DESIGN: Retrospective, population-based cohort study. SETTING: Ontario, Alberta, and British Columbia, Canada, 2008-2012. POPULATION: Nulliparous women in labour who delivered term singletons in cephalic position. METHODS: Histograms were used to examine the distribution of cervical dilation at time of caesarean delivery, overall and by indication for caesarean. Funnel plots were used to illustrate variation in hospital-level rates of caesarean deliveries for labour dystocia that were performed early (<4 cm dilation) or without the use of oxytocin. MAIN OUTCOME MEASURES: Cervical dilation (in centimetres) at time of caesarean delivery. RESULTS: The population-based cohort comprised 392 025 women, of whom 18.8% had a caesarean delivery. Of first-stage caesareans for labour dystocia in women who entered labour spontaneously, 13.6% (95% CI 12.9, 14.2) had dilations <4 cm [hospital-level inter-quartile range (IQR): 6.2% to 20.0%] and 29.5% (95% CI 28.6, 30.4) did not receive oxytocin to treat their dystocia (hospital-level IQR: 22.1-54.6%). CONCLUSIONS: The proportion of caesareans done before 4 cm dilation or without oxytocin varies substantially across hospitals and suggests the need for institutions to review their practices and ensure that management of labour practice guidelines are followed. TWEETABLE ABSTRACT: Many caesareans for labour dystocia are performed early during labour (<4 cm dilation) or without oxytocin.

Predictors for prolonged interval from premature rupture of membranes to spontaneous onset of labor at term.

OBJECTIVE: To identify predictors for prolonged interval from premature rupture of membranes (PROM) to spontaneous onset of labor in women presenting with PROM and low Bishop score at term. METHODS: A retrospective study of women presenting with PROM and Bishop score < 7 at term (≥37weeks) in a tertiary hospital (2013-14). Spontaneous onset of labor was defined as presence of regular uterine contractions and Bishop score ≥ 7. Women with interval from PROM to spontaneous onset of labor of <24hours (short interval group) were compared to those with interval ≥ 24 hours (prolonged interval group). Women who underwent induction of labor at < 24 hours from PROM were excluded. RESULTS: Among 625 women who met inclusion criteria, 155 (24.8%) had a prolonged interval to onset of labor. In multivariate analysis, prolonged PROM was associated with (OR, 95%CI) cervical dilatation (0.35, 0.24-0.52, p < 0.001), effacement (0.97, 0.96-0.99, p < 0.001) and uterine contraction (0.51, 0.32-0.80, p = 0.004). A multivariable prediction model including maternal age, parity, cervical dilatation and effacement, gestational age and neonatal birthweight was associated with an AUC of receiver-operator characteristic curve of 0.739 (0.631-0.847, p < 0.001) for predicting prolonged PROM. CONCLUSION: Uterine contractions and cervical examination parameters can be used for prediction of prolonged interval to spontaneous onset of labor in women with term PROM.

Myometrial cytokines and their role in the onset of labour.

Human labour is an inflammatory event, physiologically driven by an interaction between hormonal and mechanical factors and pathologically associated with infection, bleeding and excessive uterine stretch. The initiation and communicators of inflammation is still not completely understood; however, a key role for cytokines has been implicated. We summarise the current understanding of the nature and role of cytokines, chemokines and hormones and their involvement in signalling within the myometrium particularly during labour.

Comparing expectant management and spontaneous labor approaches in studying the effect of labor induction on cesarean delivery.

PURPOSE: Evidence of the impact of labor induction on cesarean delivery (CD) remains inconclusive because of differing methodological approaches. A spontaneous labor comparison group describes patterns retrospectively, whereas an expectant management comparison group prospectively evaluates a decision to induce. We examined the influence of comparison group on the association between labor induction and CD. METHODS: We studied 166,559 mother-newborn dyads from 14 National Perinatal Information Center member hospitals, 2007-2012. We included singleton births 34-42 completed weeks' gestation and excluded women with contraindications to vaginal delivery. We calculated risk ratios (RR) adjusted for hypertensive and diabetic disorders, intrauterine growth restriction, parity, and maternal age. RESULTS: When comparing induction to spontaneous labor, induction had significantly lower risk for CD at weeks 34-35 (adjusted RR [95% confidence interval (CI)]: 0.6 [0.5, 0.7] for week 34 and 0.7 [0.6, 0.8] for week 35) and higher risk at weeks 37-41 (adjusted RRs [95% CIs]: 1.8 [1.6, 2.1], 2.1 [1.9, 2.2], 1.8 [1.7, 1.9], 1.9 [1.8, 2.0], and 1.6 [1.5, 1.7], respectively). When comparing induction to expectant management, adjusted RRs [95% CIs] were significantly below 1.0 for week 34 (0.8 [0.7, 0.9]), week 36 (0.9 [0.8, 0.9]), and week 37 (0.9 [0.8, 0.9]), and were only elevated at week 40 (1.4 [1.3, 1.4]) and week 41 (1.4 [1.3, 1.5]). CONCLUSIONS: Using two different methodological approaches with the same sample, we confirm that comparing labor induction to spontaneous onset of labor, instead of expectant management of pregnancy, does not fully inform clinical practice and may lead to an exaggerated estimate of the risk of CD.

The use of cervical sonography to differentiate true from false labor in term patients presenting for labor check.

BACKGROUND: Cervical length by transvaginal ultrasound to predict preterm labor is widely used in clinical practice. Virtually no data exist on cervical length measurement to differentiate true from false labor in term patients who present for labor check. False-positive diagnosis of true labor at term may lead to unnecessary hospital admissions, obstetrical interventions, resource utilization, and cost. OBJECTIVE: We sought to determine if cervical length by transvaginal ultrasound can differentiate true from false labor in term patients presenting for labor check. STUDY DESIGN: This is a prospective observational study of women presenting to labor and delivery with labor symptoms at 37-42 weeks, singleton cephalic gestation, regular uterine contractions (≥4/20 min), intact membranes, and cervix ≤4 cm dilated and ≤80% effaced. Those patients with placenta previa and indications for immediate delivery were excluded. The shortest best cervical length of 3 collected images was used for analysis. Providers managing labor were blinded to the cervical length. True labor was defined as spontaneous rupture of membranes or spontaneous cervical dilation ≥4 cm and ≥80% effaced within 24 hours of cervical length measurement. In the absence of these outcomes, labor status was determined as false labor. Receiver operating characteristic curves were generated to assess the predictive ability of cervical length to differentiate true from false labor and were analyzed separately for primiparous and multiparous patients. The diagnostic accuracies of various cervical length cutoffs were determined. The relationship of cervical length and time to delivery was also analyzed including both use and nonuse of oxytocin. RESULTS: In all, 77 patients were included in the study; the prevalence of true labor was 58.4% (45/77). Patients who were in true labor had shorter cervical length as compared to those in false labor: median 1.3 cm (range 0.5-4.1) vs 2.4 cm (range 1.0-5.0), respectively (P < .001). The area under the receiver operating characteristic curve for primiparous patients was 0.88 (P < .001) and for multiparous patients was 0.76 (P < .01), both demonstrating good correlation. The area under the receiver operating characteristic curves were not significantly different between primiparous and multiparous (P = .23). The area under the receiver operating characteristic curve for primiparous and multiparous patients combined was 0.8 (P < .0001), indicating a good overall correlation between cervical length and its ability to differentiate true from false labor. Overall, a cervical length cutoff of ≤1.5 cm to predict true labor had the highest specificity (81%), positive predictive value (83%), and positive likelihood ratio (4.2). There were no differences in cervical length prediction between primiparous and multiparous patients. Cervical length was positively correlated with time to delivery, regardless of the use of oxytocin. CONCLUSION: In differentiating true from false labor in term patients who present for labor check, a cervical length of ≤1.5 cm was the most clinically optimal cutoff with the lowest false positive rate-due to its highest specificity-and highest positive predictive value and positive likelihood ratios. Its use to decide admission in patients at term with labor symptoms may prevent unnecessary admissions, obstetrical interventions, resource utilization, and cost.

Reprint of 'A nonlinear parameterization of multivariate electrohysterographical signals'.

Electrohysterography is a technique which measures a bioelectrical activity of a uterus. This paper presents an application of a nonlinear parameterization of multivariate electrohysterographical signals for a uterine activity assessment to improve unsatisfactory a labor prediction accuracy by methods published in literature. A multivariate sample entropy used for differentiated 4-channel electrohysterographical signals, general Spearman's correlation and a combined index being the sum of them, were tested. These nonlinear measures use joint information contained in a multivariate signal. The results confirm that the combined index provides the best assessment of uterine contractions: 87% sensitivity and 50% specificity of labor prediction in the studied data. These results should be verified in a prospective study.

Randomized Controlled Trial of Use of the Peanut Ball During Labor.

PURPOSE: The purpose of this study was to evaluate the efficacy of peanut ball use on duration of first stage labor and pushing time in women who were scheduled for elective induction of labor at ≥39 weeks gestation and planning an epidural. STUDY DESIGN AND METHODS: In this randomized controlled trial, women having labor induction and planning a labor epidural were assigned (1:1) to one of two groups: one group used a peanut ball and one group did not. Outcome variables were time spent in first stage labor and time spent pushing. Factors included group assignment (peanut ball, no peanut ball), parity (primiparous, multiparous), and race. Age and maximum oxytocin dose served as covariates. RESULTS: Among women having elective induction with epidural analgesia, use of a peanut ball reduced first stage labor duration for primiparous patients significantly more than multiparous patients, p = 0.018. There was no significant difference in the reduction of length of first stage labor for multiparous women, p = 0.057 with use of the peanut ball. Peanut ball use did not alter length of pushing time for either group, p > 0.05. CLINICAL IMPLICATIONS: Use of peanut balls may reduce total labor time to a greater degree in primiparous patients than multiparous patients having elective induction at ≥39 weeks with epidural analgesia.