Progression of the first stage of spontaneous labour

Clinical algorithms for the monitoring and management of spontaneous, uncomplicated labour and childbirth

The aim of this manuscript is to develop evidence-based clinical algorithms for the assessment and management of spontaneous, uncomplicated labour and vaginal birth. The population is pregnant women at any stage of labour, with singleton, term pregnancies considered to be at low risk of developing complications in health facilities in low and middle income countries. We searched for relevant published algorithms, guidelines, systematic reviews and primary research studies on Cochrane Library, PubMed® and Google, using terms related to spontaneous, uncomplicated labour and childbirth up to 1 June 2023. Three case scenarios were developed to cover the assessment and management of spontaneous, uncomplicated first, second and third stages of labour. The algorithms provide pathways for definition, assessments, diagnosis and links to other algorithms in this series for the management of complications. We have developed three clinical algorithms to support evidence-based decision-making during spontaneous, uncomplicated labour and vaginal birth. These algorithms may help to guide healthcare staff to institute respectful care, with appropriate interventions where needed, and potentially will reduce the unnecessary use of interventions during labour and childbirth.

A model to predict delivery time following induction of labor at term with a dinoprostone vaginal insert: a retrospective study

BACKGROUND

Dinoprostone vaginal insert is the most common pharmacological method for induction of labor (IOL); however, studies on assessing the time to vaginal delivery (DT) following dinoprostone administration are limited.

AIMS

We sought to identify the primary factors influencing DT in women from central China, at or beyond term, who underwent IOL with dinoprostone vaginal inserts.

METHODS

In this retrospective observational study, we analyzed the data of 1562 women at 37 weeks 0 days to 41 weeks 6 days of gestation who underwent dinoprostone-induced labor between January 1st, 2019, and December 31st, 2021. The outcomes of interest were vaginal or cesarean delivery and factors influencing DT, including maternal complications and neonatal characteristics.

RESULTS

Among the enrolled women, 71% (1109/1562) delivered vaginally, with median DT of 740.50 min (interquartile range 443.25 to 1264.50 min). Of the remaining 29% (453/1562), who delivered by cesarean section, 11.9% (54/453) were multiparous. Multiple linear regression analysis showed that multiparity, advanced maternal age, fetal macrosomia, premature rupture of membranes (PROM), and daytime insertion of dinoprostone were the factors that significantly influenced DT. Time to vaginal delivery increased with advanced maternal age and fetal macrosomia and decreased with multiparity, PROM, and daytime insertion of dinoprostone. A mathematical model was developed to integrate these factors for predicting DT: Y = 804.478 - 125.284 × multiparity + 765.637 × advanced maternal age + 411.511 × fetal macrosomia-593.358 × daytime insertion of dinoprostone - 125.284 × PROM.

CONCLUSIONS

Our findings may help obstetricians estimate the DT before placing a dinoprostone insert, which may improve patient management in busy maternity wards and minimize potential risks.

The evolution of the labor curve and its implications for clinical practice: the relationship between cervical dilation, station, and time during labor

The assessment of labor progress is germane to every woman in labor. Two labor disorders-arrest of dilation and arrest of descent-are the primary indications for surgery in close to 50% of all intrapartum cesarean deliveries and are often contributing indications for cesarean deliveries for fetal heart rate abnormalities. Beginning in 1954, the assessment of labor progress was transformed by Friedman. He published a series of seminal works describing the relationship between cervical dilation, station of the presenting part, and time. He proposed nomenclature for the classification of labor disorders. Generations of obstetricians used this terminology and normal labor curves to determine expected rates of dilation and fetal descent and to decide when intervention was required. The analysis of labor progress presents many mathematical challenges. Clinical measurements of dilation and station are imprecise and prone to variation, especially for inexperienced observers. Many interrelated factors influence how the cervix dilates and how the fetus descends. There is substantial variability in when data collection begins and in the frequency of examinations. Statistical methods to account for these issues have advanced considerably in recent decades. In parallel, there is growing recognition among clinicians of the limitations of using time alone to assess progress in cervical dilation in labor. There is wide variation in the patterns of dilation over time and most labors do not follow an average dilation curve. Reliable assessment of labor progression is important because uncertainty leads to both over-use and under-use of cesarean delivery and neither of these extremes are desirable. This review traces the evolution of labor curves, describes how limitations are being addressed to reduce uncertainty and to improve the assessment of labor progression using modern statistical techniques and multi-dimensional data, and discusses the implications for obstetrical practice.

Cervicovaginal Cytokines to Predict the Onset of Normal and Preterm Labor: a Pseudo-longitudinal Study

Inflammatory processes associated with human parturition are still not completely understood, not only because the gap between inflammation and the onset of labor has been difficult to study but also because of the limited knowledge about the role of cervicovaginal fluid (CVF) cytokines during the sequence of labor. We aimed to determine whether CVF cytokines could predict the onset of normal and preterm labor. Chemokines and proinflammatory and anti-inflammatory cytokines in CVF were measured in a pseudo-longitudinal manner in healthy women between 12 and 41 weeks gestation with intact fetal membranes before and during the first stage of labor. Women were grouped into five stages, from the absence of uterine activity and cervical changes to regular uterine contractions with cervix dilation > 3 cm (active phase of labor). Of 144 women with spontaneous labor, 96 gave birth at term, 48 gave birth preterm, and both groups displayed similar cytokine concentrations. We found positive correlations between proinflammatory cytokines and the initial sequence of labor, using individual cytokines and score-based data by principal component analysis (IFN-γ, TNF-α, IL-1β, IL-6) as dependent variables. The risk of labor onset increased as the concentrations of IL-6 increased (hazard ratio = 202.09, 95% confidence interval = 24.57-1662.49, P < 0.001). The IL-6 concentration predicted the onset of labor within 12 days of sampling (area under the time-dependent ROC curve = 0.785, 95% confidence interval = 0.693-0.877). Here, we showed that regardless of gestational age, the onset of labor could be predicted by the IL-6 concentration in the CVF, since the initial sequence of spontaneous labor displayed an inflammatory response expressed by the increase in proinflammatory cytokines.

Routine vaginal examinations compared to other methods for assessing progress of labour to improve outcomes for women and babies at term

BACKGROUND

Routine vaginal examinations are undertaken at regular time intervals during labour to assess whether labour is progressing as expected. Unusually slow progress can be due to underlying problems, described as labour dystocia, or can be a normal variation of progress. Evidence suggests that if mother and baby are well, length of labour alone should not be used to decide whether labour is progressing normally. Other methods to assess labour progress include intrapartum ultrasound and monitoring external physical and behavioural cues. Vaginal examinations can be distressing for women, and overdiagnosis of dystocia can result in iatrogenic morbidity due to unnecessary intervention. It is important to establish whether routine vaginal examinations are effective, both as an accurate measure of physiological labour progress and to distinguish true labour dystocia, or whether other methods for assessing labour progress are more effective. This Cochrane Review is an update of a review first published in 2013.

OBJECTIVES

To compare the effectiveness, acceptability, and consequences of routine vaginal examinations compared with other methods, or different timings, to assess labour progress at term.

SEARCH METHODS

For this update, we searched Cochrane Pregnancy and Childbirth Trials Register (which includes trials from CENTRAL, MEDLINE, Embase, CINAHL, and conference proceedings) and ClinicalTrials.gov (28 February 2021). We also searched the reference lists of retrieved studies.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) of vaginal examinations compared with other methods of assessing labour progress and studies assessing different timings of vaginal examinations. Quasi-RCTs and cluster-RCTs were eligible for inclusion. We excluded cross-over trials and conference abstracts.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed all studies identified by the search for inclusion in the review. Four review authors independently extracted data. Two review authors assessed risk of bias and certainty of the evidence using GRADE.

MAIN RESULTS

We included four studies that randomised a total of 755 women, with data analysed for 744 women and their babies. Interventions used to assess labour progress were routine vaginal examinations, routine ultrasound assessments, routine rectal examinations, routine vaginal examinations at different frequencies, and vaginal examinations as indicated. We were unable to conduct meta-analysis as there was only one study for each comparison.  All studies were at high risk of performance bias due to difficulties with blinding. We assessed two studies as high risk of bias and two as low or unclear risk of bias for other domains. The overall certainty of the evidence assessed using GRADE was low or very low.  Routine vaginal examinations versus routine ultrasound to assess labour progress (one study, 83 women and babies) Study in Turkey involving multiparous women with spontaneous onset of labour. Routine vaginal examinations may result in a slight increase in pain compared to routine ultrasound (mean difference -1.29, 95% confidence interval (CI) -2.10 to -0.48; one study, 83 women, low certainty evidence) (pain measured using a visual analogue scale (VAS) in reverse: zero indicating 'worst pain', 10 indicating no pain). The study did not assess our other primary outcomes: positive birth experience; augmentation of labour; spontaneous vaginal birth; chorioamnionitis; neonatal infection; admission to neonatal intensive care unit (NICU). Routine vaginal examinations versus routine rectal examinations to assess labour progress (one study, 307 women and babies) Study in Ireland involving women in labour at term. We assessed the certainty of the evidence as very low. Compared with routine rectal examinations, routine vaginal examinations may have little or no effect on: augmentation of labour (risk ratio (RR) 1.03, 95% CI 0.63 to 1.68; one study, 307 women); and spontaneous vaginal birth (RR 0.98, 95% CI 0.90 to 1.06; one study, 307 women). We found insufficient data to fully assess: neonatal infections (RR 0.33, 95% CI 0.01 to 8.07; one study, 307 babies); and admission to NICU (RR 1.32, 95% CI 0.47 to 3.73; one study, 307 babies). The study did not assess our other primary outcomes: positive birth experience; chorioamnionitis; maternal pain. Routine four-hourly vaginal examinations versus routine two-hourly examinations (one study, 150 women and babies) UK study involving primiparous women in labour at term. We assessed the certainty of the evidence as very low. Compared with routine two-hourly vaginal examinations, routine four-hourly vaginal examinations may have little or no effect, with data compatible with both benefit and harm, on: augmentation of labour (RR 0.97, 95% CI 0.60 to 1.57; one study, 109 women); and spontaneous vaginal birth (RR 1.02, 95% CI 0.83 to 1.26; one study, 150 women). The study did not assess our other primary outcomes: positive birth experience; chorioamnionitis; neonatal infection; admission to NICU; maternal pain. Routine vaginal examinations versus vaginal examinations as indicated (one study, 204 women and babies)  Study in Malaysia involving primiparous women being induced at term. We assessed the certainty of the evidence as low. Compared with vaginal examinations as indicated, routine four-hourly vaginal examinations may result in more women having their labour augmented (RR 2.55, 95% CI 1.03 to 6.31; one study, 204 women). There may be little or no effect on: • spontaneous vaginal birth (RR 1.08, 95% CI 0.73 to 1.59; one study, 204 women); • chorioamnionitis (RR 3.06, 95% CI 0.13 to 74.21; one study, 204 women); • neonatal infection (RR 4.08, 95% CI 0.46 to 35.87; one study, 204 babies); • admission to NICU (RR 2.04, 95% CI 0.63 to 6.56; one study, 204 babies). The study did not assess our other primary outcomes of positive birth experience or maternal pain.

AUTHORS' CONCLUSIONS

Based on these findings, we cannot be certain which method is most effective or acceptable for assessing labour progress. Further large-scale RCT trials are required. These should include essential clinical and experiential outcomes. This may be facilitated through the development of a tool to measure positive birth experiences. Data from qualitative studies are also needed to fully assess whether methods to evaluate labour progress meet women's needs for a safe and positive labour and birth, and if not, to develop an approach that does.

Manipulative Reduction for Abnormal Uterine Inclination in Vaginal Delivery

Objective

To investigate the manipulative reduction in abnormal uterine inclination in vaginal delivery.

Methods

With the independently developed uterine inclination surveyor, 40 primiparas with abnormal uterine inclination were randomly divided into two groups: treatment group (Group A, 20 cases) and control group (Group B, 20 cases). The general condition of the primipara, the labor stages, the changes in uterine inclination after treatment, postpartum hemorrhage at 2 hours, and the general condition of fetuses were observed to study the therapeutic value of manual reduction in abnormal uterine inclination.

Result

In the control group, one uterine inclination was not corrected with the change in labor process, and the pregnancy was terminated due to stagnation of the active phase. In the first stage of labor, the time spent in the treatment group (393.4 ± 31.3 mins) was significantly lower than that in the control group (440.7 ± 34.9 mins) (P = 0.001). Compared with the control group (49.8 ± 6.5 mins), the treatment group (42.6 ± 7.2 mins) also exhibited a significantly shortened second stage of labor (P = 0.02). Sixteen cases (16/20) in the treatment group returned to normal after manual reduction, and 9 cases (9/20) in the control group returned to normal with the progression of natural labor. Manual reduction could be used as an option to treat abnormal uterine inclination (P = 0.01). There was no significant difference in the third stage of labor (P = 0.2), 2-hour postpartum hemorrhage (P = 0.35), Apgar score (P = 0.64), or body weight (P = 0.76) between the two groups.

Conclusion

Manual reduction in the treatment of abnormal uterine inclination has obvious effects, shortens the birth process, and is safe for the fetus.

Associations between cervical dilatation on admission and mode of delivery, a cohort study of Norwegian nulliparous women

OBJECTIVE

To investigate associations between cervical dilatation at hospital admission and mode of delivery.

METHODS

A cohort study with data from a cluster-randomised controlled trial, the Labour Progression Study. The study population of 6511 nulliparous women with a singleton fetus in cephalic presentation with spontaneous onset of labour at term, was divided into two groups: <4 cm and ≥ 4 cm cervical dilatation on admission. Binary logistic regression comparing mode of delivery was used to estimate crude and adjusted OR with associated 95% CI.

RESULTS

Of the total study population, 56.7% were admitted with < 4 cm cervical dilatation and 43.3% with ≥ 4 cm. Women admitted with ≥ 4 cm had a significantly higher chance of spontaneous delivery, with adjusted OR of 1.28 (95% CI: 1.14-1.44), and a significantly lower risk of caesarean sections, with an adjusted OR of 0.51 (95% CI: 0.41-0.64). For operative vaginal delivery, there were no significant difference between the study groups. Intrapartum interventions as epidural analgesia and augmentation with oxytocin were lower among women admitted with ≥ 4 cm cervical dilatation.

CONCLUSION

The study found a significantly higher chance of spontaneous delivery among women admitted with ≥ 4 cm. More research is needed to investigate why so many women are admitted early in labour, and how these women can be better cared for to increase their chances of a spontaneous delivery.

Middle-East OBGYN graduate education (MOGGE) foundation practice guidelines: use of labor charts in management of labor. Practice guideline no. 04-O-21

Since the 50 s of the last century, labor charts have been proposed and appraised as a tool to diagnose labor abnormalities and guide decision-making. The partogram, the most widely adopted form of labor charts, has been endorsed by the world health organization (WHO) since 1994. Nevertheless, recent studies and systematic reviews did not support clinical significance of application of the WHO partogram. These results have led to further studies that investigate modifications to the structure of the partogram, or more recently, to reconstruct new labor charts to improve their clinical efficacy. This guideline appraises current evidence on use of labor charts in management of labor specially in low-resource settings.