Prolonged second stage of labor and risk of adverse maternal and perinatal outcomes: a systematic review

Optimizing labor duration with pilates: evidence from a systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Pilates has captured interest due to its possible advantages during pregnancy and childbirth. Although research indicates that Pilates may reduce labor duration, alleviate pain, and improve satisfaction with the childbirth experience, consensus on these outcomes remains elusive, underscoring the necessity for additional studies.

AIM

This systematic review and meta-analysis aimed to assess the impact of Pilates exercises on labor duration among pregnant women.

METHODS

The online database was searched to yield the literature using the terms of 'Pilates', 'childbirth', and 'labor duration', and similar terms including PubMed, Clinical Key, Scopus, Web of Science, Embase, and Cochrane Database of Systematic Reviews up to June 25, 2023. Studies were considered eligible if they were randomized or clinical controlled trials (RCTs/CCTs) published in English, focusing on healthy pregnant women without exercise contraindications. The studies needed to include interventions involving Pilates or exercise movement techniques, a comparison group with no exercise, and outcomes related to labor duration, the period of the active phase, and the second stage of delivery.

RESULTS

Eleven studies, totalling 1239 participants, were included in the analysis. These studies provided high-quality evidence from exercise only RCTs/CCTs. The findings indicated a significant reduction in the active phase of labor (8 RCTs, n = 1195; Mean Difference [MD] = -56.35, 95% Confidence Interval [CI] [-89.46 to -23.25]) and overall labor duration (8 RCTs, n = 898; MD = -93.93, 95% CI [-138.34 to -49.51]) in pregnant women who engaged in Pilates exercises compared to those who did not but doesn't affect on the duration of the second stage of labor (7 RCTs, n = 1135; MD = -0.11, 95% CI [-7.21 to 6.99]).

CONCLUSIONS

While this review primarily addresses the effects of Pilates on healthy and low-risk pregnant women, the findings suggest a potential role for Pilates in shortening labor duration. Therefore, engaging in Pilates or similar physical activities is recommended for pregnant women to potentially facilitate a more efficient labor process.

Prolonged second stage of labor and risk of postpartum hemorrhage in nullipara with epidural anesthesia and vaginal delivery: A cohort study with propensity score analysis

OBJECTIVE

To conduct an analysis using propensity score methods, exploring the association between a prolonged second stage (>3 h) and the risk of postpartum hemorrhage (PPH) in a diverse population.

METHODS

We conducted a prospective cohort study involving nullipara with epidural anesthesia and vaginal delivery, aged ≥18 years, presenting cephalically, and with a gestational age (GA) of ≥24 weeks at a tertiary maternity hospital in China (chictr.org.cn identifier: ChiCTR2200063094). Women undergoing emergency cesarean section in labor were excluded. The primary outcome was PPH, with secondary outcomes including severe postpartum hemorrhage and blood transfusion. We employed propensity score overlap weighting to analyze the association between prolonged second stage labor and PPH.

RESULTS

The study included 3643 nullipara with epidural anesthesia, comprising 77 with a second stage of labor >3 h and 3566 with a second stage ≤3 h. Utilizing propensity score overlap weighting, there were no significant differences observed between the two groups regarding the risk of PPH (29.87% in >3 h group vs 17.64% in ≤3 h group; weighted odds ratio 1.01; 95% CI: 0.51-2.02). Subgroup interaction tests for PPH were not significant for assisted vaginal delivery, induction of labor, macrosomia, third-/fourth-degree perineal laceration, GA >41 weeks, twin pregnancies, episiotomy and GA >37 weeks. Sensitivity analysis did not reveal significant differences.

CONCLUSION

This study did not find evidence supporting an increased risk of PPH associated with a second stage of labor lasting >3 h in our population, providing additional evidence for clinical practice.

Engaging women to set the research agenda for assisted vaginal birth

INTRODUCTION

Public and patient involvement can provide crucial insights to optimise research by enhancing relevance and appropriateness of studies. The World Health Organization (WHO) engaged in an inclusive process to ensure that both technical experts and women had a voice in defining the research gaps and needs to increase or reintroduce the use of assisted vaginal birth (AVB) in settings where this intervention is needed but unavailable or underused.

METHODS

We describe the methods and outcomes of online workshops led by WHO to obtain women representatives' perspectives about AVB research gaps and needs.

RESULTS

After technical experts created a list of research questions based on various evidence syntheses, WHO organised four online workshops with 31 women's representatives from 27 mostly low- and middle-income (LMIC) countries. Women rated the importance and priority of the research questions proposed by the technical experts, improving and broadening some of them, added new questions, and voiced their main concerns and views about AVB. Women helped to put the research questions into context in their communities, highlighted neglected factors/dimensions that influence practices and affect women's experience during labour and childbirth, underscored less salient consequences of AVB, and highlighted the main concerns of women about research on AVB. The consolidated vision of technical experts and women's representatives resulted in a technical brief published by WHO. The technical brief is expected to stimulate global research and action closely aligned with women's priorities.

CONCLUSIONS

We describe a successful experience of engaging women, mostly from LMICs, in the identification of research gaps and needs to reintroduce AVB use. This process contributed to better aligning research questions with women's views, concerns, and priorities. Given the scarcity of reports about engaging women from LMICs to optimise research, this successful experience can serve as an inspiration for future work.

PATIENT OR PUBLIC CONTRIBUTION

Women representatives were involved at every stage of the workshops described in full in this manuscript.

The Association of Maternal Satisfaction with Childbirth by Length of Second Stage

OBJECTIVE

The aim of this study was to quantify patient satisfaction by hour of second stage of labor and subsequent delivery mode.

STUDY DESIGN

Pilot cross-sectional study of nulliparous women delivered at George Washington University Hospital between April 2018 and March 2019. Patients completed three survey questionnaires in the immediate postpartum period: Patient Perception Score (PPS), Consumer Satisfaction Questionnaire (CSQ), and Six Simple Questions (SSQ). Length of second stage was divided into 2 groups (≤3 hours and >3 hours). Data on maternal characteristics, maternal outcomes, and neonatal outcomes were collected in REDCap and statistical analysis was performed using SAS version 9.4.

RESULTS

Survey response rate was 100% (n = 100). Seventy-one patients had a normal second stage and 29 patients had a prolonged second stage. Prolonged second stage was significantly associated with a lower proportion of NSVD (65.5 vs. 90.1%; p <0.01) and a higher proportion of epidural (82.8 vs. 60.6%; p = 0.03) in comparison to a normal second stage. Length of second stage had a statistically significant negative correlation with overall PPS scores (ρ =  - 0.25, p ≤0.01). Length of second stage was not correlated with the SSQ (ρ = 0.05, p = 0.25) or CSQ (ρ =  - 0.18, p = 0.11) surveys. CSQ scores were statistically significantly lower in women who underwent second stage cesarean delivery.

CONCLUSION

Maternal satisfaction with childbirth and health care experience was high regardless of length of second stage. Only the PSS survey showed that shorter length of second stage was correlated with higher satisfaction. Cesarean delivery in the second stage was significantly associated with decreased maternal satisfaction. Future studies with larger cohorts are needed to confirm our findings.

KEY POINTS

· There is limited data on maternal satisfaction with childbirth.. · Mode of delivery may affect maternal satisfaction.. · Shared decision-making about delivery mode and timing is crucial..

Maternal outcomes using delayed pushing versus immediate pushing in the second stage of labour: An umbrella review

INTRODUCTION

Different systematic reviews have been developed in the last decades about maternal risks of immediate pushing and delayed pushing, depending on the duration of the second stage of labour, but they do not provide conclusive evidence.

AIM

The main aim of this overview of systematic reviews was to assess the maternal outcomes using delayed pushing and immediate pushing in the second stage of labour in women receiving epidural analgesia.

METHODS

We searched systematically in PubMed (Medline), EMBASE, CINAHL, and Scopus (October 26th, 2023). Methodological quality was analysed using AMSTAR and ROBIS scales, and the strength of evidence was established according to the guidelines advisory committee grading criteria. The outcome measures were the duration of the second stage of labour, duration of active pushing, caesarean section, instrumental vaginal birth, spontaneous vaginal birth, fatigue score, perineal lacerations, postpartum haemorrhage, and rate of episiotomy. Seven systematic reviews with and without meta-analysis were included.

RESULTS

Results showed that delayed pushing increases the total time of the second stage of labour, although delayed pushing decreases the duration of active pushing with moderate quality of evidence. Mixed results were found with respect to the variables instrumental vaginal birth, spontaneous vaginal birth, and fatigue score although the results favour delayed pushing or show no statistically significant differences with respect to immediate pushing. No favourable results were ever found for immediate pushing with respect to delayed pushing, with a limited quality of evidence. Even so, delayed pushing seems to be associated with a significant increase in spontaneous vaginal birth rates. The results found no significant differences between the immediate pushing and delayed pushing groups in the caesarean section rates, perineal lacerations, postpartum haemorrhage, and episiotomy ratio, with a limited quality of evidence.

CONCLUSIONS

This study shows that delayed pushing during the second stage of labour produces at least the same maternal outcomes as immediate pushing, although we note that delayed pushing produces an increase of the duration of the second stage of labour, a shorter duration of the active pushing and a tendency to increase spontaneous vaginal birth and to reduce the instrumental vaginal birth rates and fatigue scores. This should be considered clinically. This review was registered in the International Prospective Register of Systematic Reviews PROSPERO (CRD42023397616).

Evaluation of labor management practices during spontaneous labor

INTRODUCTION

In 2017, the French national authority for health issued national guidelines to support physiologic labor and reduce medical interventions. This study's primary aim was to evaluate the association between the publication of these guidelines and the vaginal delivery rate in a type IIb perinatal center. The secondary objectives were to evaluate the implementation of these guidelines, their association with the duration of labor, and the rates of postpartum hemorrhage and adverse neonatal outcomes.

MATERIAL AND METHODS

A before-and-after, retrospective, single-center study comparing a "before" group (2016) and an "after" group (2018), one year after the recommendations were published. Women were eligible if they had no prior cesarean delivery and gave birth after 37 weeks of gestation to a singleton fetus in cephalic presentation after spontaneous labor. The analysis was stratified by parity.

RESULTS

Oxytocin administration decreased between the two periods (48% vs 35 %, P < 0.0001), as did the frequency of amniotomies (artificial rupture of membranes) (39.5 % vs 27.7 %, P < 0.0001). The duration of labor was significantly prolonged (360 vs 390 min, P < 0.0001), especially in nulliparous women (465 min vs 562 min, P<0.0001). The frequency of vaginal delivery rose between the two periods (94.6 % vs 96 %, P = 0.05), and the postpartum hemorrhage rate fell (6 % vs 4.5 %, P = 0.04). The numbers of neonates with an umbilical artery pH< 7.10 and of neonatal transfers also decreased.

CONCLUSIONS

The reduction of active interventions during labor is associated with a longer duration of labor and a decrease in the rates of cesarean births, postpartum hemorrhages, and neonatal transfers.

Prolonged second stage of labor: Predictors of adverse maternal and perinatal outcomes in a sub-Saharan setting

OBJECTIVE

To determine the predictors of adverse maternal and perinatal outcomes among parturients with prolonged second stage of labor.

METHODS

This study is a cross-sectional study of women with prolonged second stage of labor from January 1 to June 30, 2021, in four tertiary hospitals in Ethiopia. Data were collected prospectively using a structured questionnaire. Descriptive statistics were used to analyze baseline characteristics. Bivariate and multivariate logistic regression analyses were applied to determine predictors of adverse maternal and perinatal outcomes.

RESULTS

A total of 406 women were included in the study. More than half (25/46, 54%) of the women with a prolonged second stage of 4 h or longer had vaginal delivery, which was lower than the 73% (140/190) of women who had a second stage of 2-3 h and the 63.4% (64/101) of women with a second stage duration of 3-4 h. Duration of second stage of labor was not a predictor of composite adverse maternal outcomes nor was it a predictor of adverse perinatal outcome. Operative vaginal delivery (adjusted odds ratio [aOR] 6.0, 95% confidence interval [CI] 2.41-14.9) and nulliparity (aOR 4.1, 95% CI 1.58-10.41) were predictors of adverse maternal outcome, but nulliparity (aOR 1.8, 95% CI 1.05-3.04) and duration of rupture of membranes greater than 18 h (aOR 2.4, 95% CI 1.21-4.93) were predictors of adverse perinatal outcomes.

CONCLUSION

Under strict fetal and maternal well-being monitoring, women with a prolonged second stage of labor can labor for an additional 2 h (up to a total of 4 h) without increasing adverse maternal and neonatal outcomes.

Maternal and perinatal outcomes of prolonged second stage of labour: a historical cohort study of over 51,000 women

BACKGROUND

Prolonged second stage of labour has been associated with adverse maternal and perinatal outcomes. The maximum length of the second stage from full dilatation to birth of the baby remains controversial. Our aim was to determine whether extending second stage of labour was associated with adverse maternal and perinatal outcomes.

METHODS

A retrospective cohort study was conducted using routinely collected hospital data from 51592 births in Aberdeen Maternity Hospital between 2000 and 2016. The hospital followed the local guidance of allowing second stage of labour to extend by an hour compared to national guidelines since 2008 (nulliparous and parous). The increasing duration of second stage of labour was the exposure. Baseline characteristics, maternal and perinatal outcomes were compared between women who had a second stage labour of (a) ≤ 3 h and (b) > 3 h duration for nulliparous women; and (a) ≤ 2 h or (b) > 2 h for parous women. An additional model was run that treated the duration of second stage of labour as a continuous variable (measured in hours). All the adjusted models accounted for: age, BMI, smoking status, deprivation category, induced birth, epidural, oxytocin, gestational age, baby birthweight, mode of birth and parity (only for the final model).

RESULTS

Each hourly increase in the second stage of labour was associated with an increased risk of obstetric anal sphincter injury (aOR 1.21 95% CI 1.16,1.25), having an episiotomy (aOR 1.48 95% CI 1.45, 1.52) and postpartum haemorrhage (aOR 1.27 95% CI 1.25, 1.30). The rates of caesarean and forceps delivery also increased when second stage duration increased (aOR 2.60 95% CI 2.50, 2.70, and aOR 2.44 95% CI 2.38, 2.51, respectively.) Overall adverse perinatal outcomes were not found to change significantly with duration of second stage on multivariate analysis.

CONCLUSIONS

As the duration of second stage of labour increased each hour, the risk of obstetric anal sphincter injuries, episiotomies and PPH increases significantly. Women were over 2 times more likely to have a forceps or caesarean birth. The association between adverse perinatal outcomes and the duration of second stage of labour was less convincing in this study.

Perinatal maternal characteristics predict a high risk of neonatal asphyxia: A multi-center retrospective cohort study in China

Objective

This study aimed to identify various perinatal maternal characteristics that contributed to neonatal asphyxia (NA) in term and late-preterm newborns based on the data obtained from a Chinese birth registry cohort and to establish an effective model for predicting a high risk of asphyxia.

Method

We retrospectively reviewed and analyzed the birth database from July 1, 2016, to June 30, 2017, in the main economically developed regions of China. Asphyxia was defined as an Apgar score <7 at 5 min post-delivery with umbilical cord arterial blood pH < 7.2 in the infant born after 34weeks. We compared the perinatal maternal characteristics of the newborns who developed asphyxia (NA group, n = 1,152) and those who did not (no NA group, n = 86,393). Candidate predictors of NA were analyzed using multivariable logistic regression. Subsequently, a prediction model was developed and validated by an independent test group.

Result

Of the maternal characteristics, duration of PROM ≥ 48 h, a gestational week at birth <37, prolonged duration of labor, hypertensive disorder, nuchal cord, and birth weight <2,500 or ≥4,000 g, abnormal fetal heart rate, meconium-stained amniotic fluid, and placenta previa were included in the predicting model, which presented a good performance in external validation (c-statistic of 0.731).

Conclusion

Our model relied heavily on clinical predictors that may be determined before or during birth, and pregnant women at high risk of NA might be recognized earlier in pregnancy and childbirth using this methodology, allowing them to avoid being neglected and delayed. Future studies should be conducted to assess its usefulness.

Associations between prolonged second stage of labor and maternal and neonatal outcomes in freestanding birth centers: a retrospective analysis

BACKGROUND

Current guidelines for second stage management do not provide guidance for community birth providers about when best to transfer women to hospital care for prolonged second stage. Our goal was to increase the evidence base for these providers by: 1) describing the lengths of second stage labor in freestanding birth centers, and 2) determining whether proportions of postpartum women and newborns experiencing complications change as length of second stage labor increases.

METHODS

This study is a retrospective analysis of de-identified client-level data collected in the American Association of Birth Centers Perinatal Data Registry, including women giving birth in freestanding birth centers January 1, 2007 to December 31, 2016. We plotted proportions of postpartum women and newborns transferred to hospital care against length of the second stage of labor, and assessed significance of these with the Cochran-Armitage test for trend or chi-square test. Secondary maternal and newborn outcomes were compared for dyads with normal and prolonged second stages of labor using Fisher's exact test.

RESULTS

Second stage labor exceeded 3 hours for 2.3% of primiparous women and 2 hours for 6.6% of multiparous women. Newborn transfers increased as second stage increased from < 15 minutes to > 2 hours (0.6% to 6.33%, p for trend = 0.0008, for primiparous women, and 1.4% to 10.6%, p for trend < 0.0001, for multiparous women.) Postpartum transfers for multiparous women increased from 1.4% after second stage < 15 minutes to greater than 4% for women after second stage exceeding 2 hours (p for trend < 0.0001.) CONCLUSIONS: Complications requiring hospitalization of postpartum women and newborns become more common as the length of the second stage increases. Birth center guidelines should consider not just presence of progress but also absolute length of time as indications for transfer.

Intrapartum ultrasound measurement of angle of progression at the onset of the second stage of labor for prediction of spontaneous vaginal delivery in term singleton pregnancies: a systematic review and meta-analysis

OBJECTIVE

This study aimed to investigate the diagnostic performance of transperineal ultrasound-measured angles of progression at the onset of the second stage of labor for the prediction of spontaneous vaginal delivery in singleton term pregnancies with cephalic presentation.

DATA SOURCES

We performed a predefined systematic search in PubMed, Embase, Scopus, Web of Science, and Google Scholar from inception to February 5, 2021.

STUDY ELIGIBILITY CRITERIA

Prospective cohort studies that evaluated the diagnostic performance of transperineal ultrasound-measured angles of progression (index test) at the onset of the second stage of labor (ie, when complete cervical dilation is diagnosed) for the prediction of spontaneous vaginal delivery (reference standard) were eligible for inclusion. Eligible studies were limited to those published as full-text articles in the English language and those that included only parturients with a singleton healthy fetus at term with cephalic presentation.

STUDY APPRAISAL AND SYNTHESIS METHODS

Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Summary receiver operating characteristic curves, pooled sensitivities and specificities, area under the curve, and summary likelihood ratios were calculated using the Stata software. Subgroup analyses were done based on angle of progression ranges of 108° to 119°, 120° to 140°, and 141° to 153°.

RESULTS

A total of 8 studies reporting on 887 pregnancies were included. Summary estimates of the sensitivity and specificity of transperineal ultrasound-measured angle of progression at the onset of the second stage of labor for predicting spontaneous vaginal delivery were 94% (95% confidence interval, 88%-97%) and 47% (95% confidence interval, 18%-78%), respectively, for an angle of progression of 108° to 119°, 81% (95% confidence interval, 70%-89%) and 73% (95% confidence interval, 57%-85%), respectively, for an angle of progression of 120° to 140°, and 66% (95% confidence interval, 56%-74%) and 82% (95% confidence interval, 66%-92%), respectively, for an angle of progression of 141° to 153°. Likelihood ratio syntheses gave overall positive likelihood ratios of 1.8 (95% confidence interval, 1-3.3), 3 (95% confidence interval, 2-4.7), and 3.7 (95% confidence interval, 1.7-8.1) and negative likelihood ratios of 0.13 (95% confidence interval, 0.07-0.22), 0.26 (95% confidence interval, 0.18-0.38), and 0.42 (95% confidence interval, 0.29-0.60) for angle of progression ranges of 108° to 119°, 120° to 140°, and 141° to 153°, respectively.

CONCLUSION

Angle of progression measured by transperineal ultrasound at the onset of the second stage of labor may predict spontaneous vaginal delivery in singleton, term, cephalic presenting pregnancies and has the potential to be used along with physical examinations and other clinical factors in the management of labor and delivery.

Association between second stage of labour length and risk of obstetrical anal sphincter injury in nulliparous women: a population-based retrospective cohort study

INTRODUCTION AND HYPOTHESIS

Obstetrical anal sphincter injury (OASIS) is a common consequence of vaginal delivery in nulliparas and carries the risk of short- and long-term morbidity. The objective of this study was to estimate the association between the duration of the second stage of labour and OASIS risk.

METHODS

A population-based, retrospective cohort of nulliparas delivering singleton, vertex, non-anomalous fetuses at term in Nova Scotia, Canada, from 2005 to 2019, were identified using the Nova Scotia Atlee Perinatal Database. Poisson regression models were used to estimate risk ratios (RR) with robust 95% confidence intervals (CI) adjusting for confounding variables to investigate the association between the length of the second stage and OASIS in the entire cohort and in operative vaginal deliveries.

RESULTS

Of 36,662 participants, 7.6% sustained an OASIS (6.8% third-degree, 0.8% fourth-degree tear). The proportion of participants who sustained an OASIS increased over the study period. For each 30-min increase in the length of second stage, the OASIS risk increased by 11% (RR 1.11, 95% CI 1.10-1.12). When stratified by mode of delivery, second stage length ≥ 90 min was associated with an increased OASIS risk in spontaneous (RR 1.35, 95% CI 1.15-1.58) and vacuum-assisted vaginal deliveries (RR 1.42, 95% CI 1.11-1.81). In forceps-assisted vaginal deliveries, OASIS risk was increased, with shorter and longer durations of the second stage.

CONCLUSION

Increasing length of the second stage of labour was associated with increasing risk of OASIS overall, but the association was heterogeneous between modes of delivery. Length of the second stage should be considered in counseling about OASIS risk.

Association between ultrasound measured angle of progression and remaining time in labor: a systematic review

OBJECTIVES

To evaluate the association between ultrasound measured angle of progression (AoP) during labor and time to delivery (TTD) or second stage of labor duration (SSLD).

METHODS

This systematic review (SR) was reported according to PRISMA statement 2020. Databases investigated were MEDLINE, CINHAL, Embase, Scopus, Web of Science. Other sources were references or related articles of included studies, Google Scholar, clinicaltrials.gov, thesis, expert groups. Main keywords: angle of progression, transperineal ultrasound, delivery, labor. Inclusion criteria were observational studies, single term pregnancy, cephalic presentation, AoP measurement during the first stage of labor or at the beginning of the second stage, without date restrictions. Language included: English, Italian, French, Spanish. Studies selection, evaluation of the risk of bias with Quality in Prognosis Studies (QUIPS) tool, and data extraction were carried out by two authors blindly and independently, with disagreement resolution by a third author. Qualitative summary of the results. This SR was registered on PROSPERO, number CDR42021232015.

RESULTS

Of 428 records, 14 were included, published from 2009 to 2021, cumulatively analyzing 2498 women. All studies highlighted an inverse relationship between AoP and TTD. Some have identified an AoP cutoff, contained in a range between 110° and 129°, beyond which the duration of labor is significantly shorter. Others, a range between 137° and 160°, beyond which the duration of the expulsive period is significantly shorter. Finally, some factors influence this association: parity, epidural, and oxytocin.

CONCLUSIONS

This SR confirms a significant association between AoP in labor and TTD. In clinical practice, AoP could help to predict the duration of labor, facilitating decision-making. The main limitations of this SR were the low number of included studies, their heterogeneity, and the high risk of bias related to confounding factors. For future research, further studies are needed to increase the strength of the evidence, obtain stratified results according to patients' characteristics and investigate groups of patients who have not yet been evaluated.

Evidence-based labor management: second stage of labor (part 4)

Several interventions during the second stage of labor have been identified and investigated. Prophylactic intrapartum betamimetics should be avoided, as their usage is associated with an increase in operative vaginal deliveries. Women without epidural anesthesia are recommended to give birth in in any upright or lateral position. The best position for giving birth in women with epidural anesthesia is insufficiently studied, and neither recumbent nor upright positions can therefore be recommended. The routine use of maternal stirrups in the second stage of labor is not recommended. Consider avoiding water immersion during the second stage of labor, as the risks have not been adequately assessed. In nulliparous women at term with epidural analgesia, delayed pushing is not recommended. Pushing via a woman's own urge to push (open glottis) or pushing using the Valsalva maneuver (closed glottis) can both be considered. Both traditional coaching during pushing and ultrasound-assisted coaching may be considered. The use of a dental support device can be considered. All forms of fundal pressure are not recommended in the second stage of labor. Perineal massage and stretching of the perineum with a water-soluble lubricant in the second stage of labor is recommended. Perineal hyaluronidase injection as a method to reduce perineal trauma is not recommended. The use of perineal gel in the second stage of labor is not recommended. The use of perineal warm packs and heating pads are recommended. A perineal protection device can be considered. In fetuses with persistent occiput posterior position, manual rotation can be considered. Routine use of the Ritgen's maneuver does not seem to be associated with any benefits and is not recommended. The "Hands-poised" position is recommended over the "hands-on" method for delivery of the fetus. Routine episiotomy is not recommended. The routine use of ultrasound in the second stage of labor is not recommended. Waiting 1 additional hour (4 hours) for nulliparous women with epidural anesthesia before the diagnosis of a prolonged second stage of labor is recommended. A mandatory second opinion before cesarean delivery in the second stage of labor is recommended.

Duration of the pushing phase of labor is inversely associated with expression of TNF, IL6, IGF1 and IGF2 in human placenta

OBJECTIVE

Gene expression in placenta differs between vaginal and cesarean deliveries, but the influence of the duration of labor on placental gene expression is incompletely known. Our aim was to investigate associations between duration of labor and expression of some genes involved in growth or inflammation in human placental tissue.

METHODS

Placenta samples (n = 126) were collected after an uncomplicated, singleton pregnancy and term vaginal delivery at Örebro University Hospital, Sweden. Duration of labor was recorded by the midwife in the delivery room. The expression of the following genes was analyzed by RT-qPCR: tumor necrosis factor (TNF), interleukin-6 (IL6), C-X-C motif chemokine ligand 8, toll-like receptor (TLR) 2, TLR4, insulin receptor, insulin-like growth factor (IGF) 1, IGF2, leptin, hepatocyte growth factor (HGF) and HGF receptor (MET). Multivariable linear regression models were used for the evaluation of associations with labor duration adjusting for potential confounding factors. The Benjamini-Hoschberg method was used to correct for multiple testing.

RESULTS

The expression of TNF, IL6, IGF1 and IGF2 was inversely associated with the duration of the pushing phase of labor (B coefficients (95% confidence interval) = -0.150 (-0.277 to -0.023), -0.159 (-0.289 to -0.029), -0.099 (-0.176 to -0.021), and -0.081 (-0.145 to -0.017), respectively).

CONCLUSIONS

Longer duration of pushing is associated with downregulation of the expression of genes in placenta from vaginal deliveries. Future research on gene expression in labored placenta should take into account associations with labor duration and especially the pushing phase. Potential impact of these associations on the mother, the fetus and the new-born infant should also be explored.

Efficacy of phloroglucinol for acceleration of labour: a systematic review and meta‑analysis

PURPOSE

To assess the efficacy of phloroglucinol for acceleration of labour.

METHODS

Randomized controlled trials (RCTs) comparing phloroglucinol with placebo were searched in PubMed, Embase and the Cochrane Library. Literatures were collected up to April 2020. Primary outcomes were the duration of labour and average blood loss. Finally, a total of 4 RCTs, 377 patients were included in this meta-analysis. The included RCTs were analyzed by the software Rev Man 5. 3.

RESULTS

In the phloroglucinol group, the duration of the first stage was reduced by 116.04 min (95% CI 107.71 to 124.68), and the duration of the second stage was reduced by 10.75 min (95% CI 8.79 to 12.70). The average blood loss was reduced by 16.07 ml, which was statistically different from the control group.

CONCLUSION

The application of phloroglucinol is proved to be effective for accelerating the labour process, reducing the risk of maternal and neonatal complications.

Neonatal admission and mortality in babies born in UK alongside midwifery units: a national population-based case-control study using the UK Midwifery Study System (UKMidSS)

OBJECTIVES

To determine the incidence of and risk factors for neonatal unit admission, intrapartum stillbirth or neonatal death without admission, and describe outcomes, in babies born in an alongside midwifery unit (AMU).

DESIGN

National population-based case-control study.

METHOD

We used the UK Midwifery Study System to identify and collect data about 1041 women who gave birth in AMUs, March 2017 to February 2018, whose babies were admitted to a neonatal unit or died (cases) and 1984 controls from the same AMUs. We used multivariable logistic regression, generating adjusted OR (aOR) with 95% CIs, to investigate maternal and intrapartum factors associated with neonatal admission or mortality.

RESULTS

The incidence of neonatal admission or mortality following birth in an AMU was 1.2%, comprising neonatal admission (1.2%) and mortality (0.01%). White 'other' ethnicity (aOR=1.28; 95% CI=1.01 to 1.63); nulliparity (aOR=2.09; 95% CI=1.78 to 2.45); ≥2 previous pregnancies ≥24 weeks' gestation (aOR=1.38; 95% CI=1.10 to 1.74); male sex (aOR=1.46; 95% CI=1.23 to 1.75); maternal pregnancy problem (aOR=1.40; 95% CI=1.03 to 1.90); prolonged (aOR=1.42; 95% CI=1.01 to 2.01) or unrecorded (aOR=1.38; 95% CI=1.05 to 1.81) second stage duration; opiate use (aOR=1.31; 95% CI=1.02 to 1.68); shoulder dystocia (aOR=5.06; 95% CI=3.00 to 8.52); birth weight <2500 g (aOR=4.12; 95% CI=1.97 to 8.60), 4000-4999 g (aOR=1.64; 95% CI=1.25 to 2.14) and ≥4500 g (aOR=2.10; 95% CI=1.17 to 3.76), were independently associated with neonatal admission or mortality. Among babies admitted (n=1038), 18% received intensive care. Nine babies died, six following neonatal admission. Sepsis (52%) and respiratory distress (42%) were the most common discharge diagnoses.

CONCLUSIONS

The results of this study are in line with other evidence on risk factors for neonatal admission, and reassuring in terms of the quality and safety of care in AMUs.

Prolonged second stage effect on pelvic floor dysfunction: a follow up survey to a randomized controlled trial

BACKGROUND

Pelvic floor dysfunction is a group of disorders that can significantly impact quality of life due to persistent urinary and anal incontinence. Data evaluating the effect of prolonged second stage of labor and postpartum pelvic floor dysfunction is heterogenous and limited.

OBJECTIVE

To evaluate whether extending the length of labor in nulliparous women with prolonged second stage affects the presence of self-reported pelvic floor dysfunction after a randomized controlled trial of prolonged second stage.

STUDY DESIGN

We conducted a planned follow up survey to our randomized controlled trial of prolonged second stage of labor using the Pelvic Floor Distress Inventory-20 (PFDI-20). The primary outcome was the PFDI-20 summary score. Secondary outcomes included urinary and fecal incontinence, prolapse, and patient satisfaction. Women surveyed were nulliparous patients with epidural anesthesia, previously enrolled in a randomized controlled trial that assigned them to extended labor, at least 1 additional hour in the second stage if they were undelivered after three hours, or to usual labor, defined as expedited delivery after three hours in the second stage. Women were surveyed at 12 - 36 months postpartum.

RESULTS

Thirty-four of the seventy-eight women responded to the survey (43.6%). 17 women (50.0%) were from the extended labor group and 17 from the usual labor group (50.0%). Maternal demographic data were not significantly different between groups. The PFDI-20 summary score was 13.8 ± 23.3 in the extended labor group and 13.1 ± 20.9 in the usual labor group (p = 0.9). The Pelvic Organ Prolapse Distress Inventory-6 was 1.2 ± 2.9 in the extended labor group and 2.7 ± 6.4 in the usual labor group (p = 0.4). The Colorectal-Anal Distress Inventory-8 was 0.8 ± 2.8 in the extended labor group and 2.1 ± 4.0 in the usual labor group (p = 0.6). The Urinary Distress Inventory-6 was 11.8 ± 21.1 in the extended labor group and 8.3 ± 14.5 in the usual labor group (p = 0.6). Maternal and neonatal outcomes, as well as patient satisfaction, were not statistically significantly different between groups.

CONCLUSION

Extending the length of labor in nulliparas with singleton gestations, epidural anesthesia, and prolonged second stage did not have an impact on PFDI-20 scores at 12-36 months postpartum. However, our study was underpowered to detect small, but potentially clinically important, differences.

CLINICAL TRIAL NUMBER

NCT02101515 (Study Registration Date March 28, 2014) https://clinicaltrials.gov/ct2/show/NCT02101515.

Transperineal ultrasound of fetal head progression in prolonged labor: women’s acceptance and ability to predict the mode of delivery

Background

Digital transvaginal examination of fetal head progression is subjective evaluation with many limitations. Using ultrasound (US) in the assessment of labor progression in prolonged labor is the current trend to predict the mode of delivery. The study intends to evaluate the women’s acceptance to the transperineal ultrasound (TPUS) compared with digital transvaginal examination, and its ability to predict the mode of delivery in prolonged labor. We included 28 pregnant ladies in a prolonged active phase of first or second stages of labor and followed them till delivery. TPUS was used to measure the fetal head–perineum distance (FHPD) and the angle of fetal head descent.

Results

Of the 28 participants, 53.5% of them delivered vaginally and 46.5% by Cesarean section (CS). All pregnant ladies described the TPUS as more convenient and less painful than digital vaginal examination. Cervical dilatation was negatively correlated with FHPD, and positively correlated with angle of fetal head descent. Both FHPD and angle of fetal head descent had a strong significant negative correlation. Using a cutoff value of 115° for the angle of fetal head descent, the positive predictive value (PPV) of vaginal delivery was 87%; using a cutoff value of 4.2 cm for FHPD, the PPV for vaginal delivery was 85%.

Conclusion

TPUS is more convenient, more accepted, and less painful than digital vaginal examination. Angle of head descent and FHPD are reliable predictors of the mode of delivery in prolonged labor.

Risks associated with cesarean delivery during prolonged second stage of labor

BACKGROUND

Data regarding maternal and fetal morbidities are limited to surgical morbidity per each additional hour in the second stage of labor.

OBJECTIVE

This study aimed to quantify perinatal morbidities associated with cesarean delivery by duration of the second stage of labor.

STUDY DESIGN

Our work is a retrospective cohort study of cesarean deliveries during the second stage of labor using the Consortium on Safe Labor database. All term, singleton pregnancies in cephalic presentation were included. Women with stillbirth or contraindications to vaginal delivery were excluded. Groups were divided by duration of the second stage of labor: ≤3 hours, 3-4 hours, 4-5 hours, 5-6 hours, and >6 hours. The primary outcome was a composite of maternal morbidities. The secondary outcomes were a composite of neonatal morbidities and individual maternal and neonatal morbidities. Baseline demographic and clinical characteristics were compared among groups. Univariate and multivariate analyses were performed.

RESULTS

We included 6273 women in total. In addition, 3652 women (58.2%) went through the second stage for ≤3 hours, 854 (13.6%) for 3 to 4 hours, 618 (9.9%) for 4 to 5 hours, 397 (6.3%) for 5 to 6 hours, and 752 (12.0%) for >6 hours. Neither the maternal nor neonatal morbidity composite outcomes were statistically different among the groups. Extended maternal length of stay (>5 days), increased birthweight, and lower rates of general anesthesia were associated with an increased duration of the second stage of labor. Chorioamnionitis, wound complications, postpartum hemorrhage, and thrombosis did not increase over time.

CONCLUSION

Women should be counseled regarding the duration of the second stage of labor, which should include a discussion of the risks associated with a cesarean delivery with a prolonged second stage of labor. However, these risks may not be as high as anticipated.

Relationship Between Prolonged Second Stage of Labor and Short-Term Neonatal Morbidity: A Systematic Review and Meta-Analysis

To evaluate the association between prolonged second stage of labor and the risk of adverse neonatal outcomes with a systematic review and meta-analysis. PubMed, Scopus and EMBASE were searched using the search strategy "Labor Stage, Second" AND (length OR duration OR prolonged OR abnormal OR excessive). Observational studies that examine the relationship between prolonged second stage of labor and neonatal outcomes were selected. Prolonged second stage of labor was defined as 4 h or more in nulliparous women and 3 h or more in multiparous women. The main neonatal outcomes were 5 min Apgar score <7, admission to the Neonatal Intensive Care Unit, neonatal sepsis and neonatal death. Data collection and quality assessment were carried out independently by the three reviewers. Twelve studies were selected including 266,479 women. In nulliparous women, a second stage duration greater than 4 h increased the risk of 5 min Apgar score <7, admission to the Neonatal Intensive Care Unit and neonatal sepsis and intubation. In multiparous women, a second stage of labor greater than 3 h was related to 5 min Apgar score <7, admission to the Neonatal Intensive Care Unit, meconium staining and composite neonatal morbidity. Prolonged second stage of labor increased the risk of 5 min Apgar score <7 and admission to the Neonatal Intensive Care Unit in nulliparous and multiparous women, without increasing the risk of neonatal death. This review demonstrates that prolonged second stage of labor increases the risk of neonatal complications in nulliparous and multiparous women.

Maternal and neonatal outcomes following a prolonged second stage of labor: A meta-analysis of observational studies

Several articles investigated the impact of prolonged second stage of labor on maternal and neonatal outcomes; however, strict consensus is still lacking. The purpose of the present meta-analysis is to investigate risk factors that contribute to the pathophysiology of prolonged labor as well as effect sizes of maternal and neonatal morbidity. We searched Medline, Scopus, Clinicaltrials.gov, EMBASE, Cochrane Central Register of Controlled Trials CENTRAL and Google Scholar database. Observational studies (prospective and retrospective) were considered eligible for inclusion in the present meta-analysis. To minimize the possibility of article losses we avoided language, country and date restrictions. Meta-analysis was performed with the RevMan 5.3 and secondary analysis with Rstudio. Overall, 13 studies were included in the present systematic review that comprised 337.845 parturient. Prolonged second stage was associated with higher odds of postpartum hemorrhage, chorioamnionitis, endometritis, postpartum fever and obstetric anal sphincter injury. Persistent occiput posterior position and shoulder dystocia were also more prevalent compared to women with normal duration of the second stage. The need for admission to the neonatal intensive care unit was higher as well as the risk of developing neonatal sepsis. On the other hand, the odds of perinatal death were comparable among cases with prolonged and normal duration of the second stage. The results of the present meta-analysis clearly indicate that deliveries following a prolonged second stage of labor are at increased risk of maternal and neonatal complications. The presented effect estimates can be used in current clinical practice during patient counseling.

Augmentation of labor with oxytocin and its association with delivery outcomes: A large-scale cohort study in 12 public hospitals in Nepal

INTRODUCTION

The use of oxytocin to augment labor is increasing in many low-resource settings; however, little is known about the effects of such use in contexts where resources for intrapartum monitoring are scarce. In this study, we sought to assess the association between augmentation of labor with oxytocin and delivery outcomes.

MATERIAL AND METHODS

We conducted a cohort study in 12 public hospitals in Nepal, including all deliveries with and without augmentation of labor with oxytocin, but excluding elective cesarean sections, women with missing information on augmentation of labor, and women without fetal heart rate on admission. Bivariate and multivariate logistic regression calculating the crude and adjusted risk ratio (aRR) with corresponding 95% CI were performed, comparing (a) intrapartum stillbirth and first-day mortality (primary outcome); and (b) intrapartum monitoring, mode of delivery, postpartum hemorrhage, bag-and-mask ventilation of the newborn, Apgar score, and neonatal death before discharge (secondary outcomes) among women with and without oxytocin-augmented labor.

RESULTS

The total cohort consisted of 78 931 women, of whom 28 915 (37%) had labor augmented with oxytocin and 50 016 (63%) did not have labor augmented with oxytocin. Women with augmentation of labor had no increased risk of intrapartum stillbirth and first-day mortality (aRR 1.24, 95% CI 0.65-2.4), but decreased risks of suboptimal partograph use (aRR 0.71, 95% CI 0.68-0.74), suboptimal fetal heart rate monitoring (aRR 0.50, 95% CI 0.48-0.53), and emergency cesarean section (aRR 0.62, 95% CI 0.59-0.66), and increased risks of bag-and-mask ventilation (aRR 2.1, 95% CI 1.8-2.5), Apgar score <7 at 5 minutes (aRR 1.65, 95% CI 1.49-1.86), and neonatal death (aRR 1.93, 95% CI 1.46-2.56).

CONCLUSIONS

Although augmentation of labor with oxytocin might be associated with beneficial effects, such as improved monitoring and a decreased risk of cesarean section, its use may lead to an increased risk of adverse perinatal outcomes. We urge for a cautious use of oxytocin to augment labor in low-resource contexts, and call for evidence-based guidelines on augmentation of labor in low-resource settings.

Key indicators influencing management of prolonged second stage labour by midwives in freestanding birth centres: Results from an ethnographic interview study

PROBLEMS

Complications for newborns and postpartum clients in the hospital are more frequent after a prolonged second stage of labour. Midwives in community settings have little research to guide management in their settings.

AIM

We explored how US birth centre midwives identify onset of second stage of labour and determine when to transfer clients to the hospital for prolonged second stage.

METHODS

Ethnographic interviews of midwives with at least 2 years' experience in birth centres and participant observation of birth centre care.

FINDINGS

We interviewed 21 midwives (18 CNMs, 3 CPMs/equivalent) from 18 birth centres in 11 US states, 45% with hospital practice privileges. Midwives relied on and engaged in embodied practice in evaluating each labour and making decisions concerning management of labour. Midwives considered time a useful but limited measure as a guiding factor in management. Though ideas of time and progress do play an important role in the decision-making process of midwives, their usefulness is limited due to the continual, multifactorial, and multisensory nature of the assessment. Relationship with the transfer hospital structured midwives' decision-making about transfers.

DISCUSSION & CONCLUSION

These findings can inform future robust multivariate evaluation of factors, including but not limited to time, in guidelines for management of second stage of labour. Optimal management may require formal consideration of more than just time and parity. Our findings also suggest the need for evaluation of how structural issues involving hospital privileges for midwives and relationships between birth centre and hospital staff affect the well-being of childbearing families.

The second stage of labor

The second stage of labor, from full cervical dilatation to complete birth of the baby or babies, constitutes the time of greatest risk for the baby. Birth attendants at all levels require training in the skills necessary to overcome difficulties that may arise unexpectedly during the second stage, particularly poor progress, shoulder dystocia, and breech birth. The mother should receive emotional support and encouragement to bear down instinctively when she feels the urge to do so, in the position she feels enables her to push most effectively, but not the supine position. The baby's heart rate should be monitored after every second contraction. Recent guidelines such as those of the World Health Organization(WHO) recommend allowing 2-3 h for the second stage of labor. Uterine fundal pressure has not been shown to be effective, and may be dangerous. Choosing between cesarean section and assisted vaginal birth to overcome delayed second stage requires relevant skill and experience.

Maternal risk factors for adverse outcome in asphyxiated newborns treated with hypothermia: parity and labor duration matter

Introduction: Perinatal asphyxia remains a frequent cause of neonatal mortality and long-term neurodevelopmental sequelae, despite the introduction of therapeutic hypothermia. Specific maternal characteristics may predispose asphyxiated newborns treated with hypothermia to worse outcome.Objective: To investigate the possible association between specific maternal factors and adverse outcome in asphyxiated newborns treated with hypothermia.Methods: We conducted a retrospective review of our database of 215 asphyxiated newborns treated with hypothermia from 2008 to 2015. We collected maternal characteristics including parity and labor duration, and we defined adverse outcome as death and/or brain injury. We compared the maternal characteristics between the asphyxiated newborns who developed adverse outcome and those who did not.Results: Asphyxiated newborns born to nulliparous mothers had a significantly higher risk of adverse outcome (61%), compared to asphyxiated newborns born from primiparous (19%) and multiparous (20%) mothers (p = .002). Labor duration was longer in nulliparous mothers (p = .04). Among mothers who delivered vaginally, labor duration was significantly longer in newborns developing adverse outcome (p = .04). In multivariable analysis, parity was confirmed as an independent predictor of adverse outcome in all newborns, but labor duration showed a borderline non-significant association with adverse outcome (p = .051) only in newborns born vaginally. Labor duration beyond 12 h of life was associated with maximal sensitivity and specificity in detecting asphyxiated newborns at an increased risk of adverse outcome despite hypothermia treatment (AUC 0.62, p = .044).Conclusions: Newborns with evidence of perinatal asphyxia, born to nulliparous mothers, and especially to those in whom the duration of labor has been prolonged, might be at higher risk of death or brain injury despite the use of therapeutic hypothermia.

Prediction of spontaneous vaginal delivery in nulliparous women with a prolonged second stage of labor: the value of intrapartum ultrasound

BACKGROUND

A limited number of studies have addressed the role of intrapartum ultrasound in the prediction of the mode of delivery in women with prolonged second stage of labor.

OBJECTIVE

The objective of the study was to evaluate the role of transabdominal and transperineal sonographic findings in the prediction of spontaneous vaginal delivery among nulliparous women with prolonged second stage of labor.

STUDY DESIGN

This was a 2-center prospective study conducted at 2 tertiary maternity units. Nulliparous women with a prolonged active second stage of labor, as defined by active pushing lasting more than 120 minutes, were eligible for inclusion. Transabdominal ultrasound to evaluate the fetal head position and transperineal ultrasound for the measurement of the midline angle, the head-perineum distance, and the head-symphysis distance were performed in between uterine contractions and maternal pushes. At transperineal ultrasound the angle of progression was measured at rest and at the peak of maternal pushing effort. The delta angle of progression was defined as the difference between the angle of progression measured during active pushing at the peak of maternal effort and the angle of progression at rest. The sonographic findings of women who had spontaneous vaginal delivery vs those who required obstetric intervention, either vacuum extraction or cesarean delivery, were evaluated and compared.

RESULTS

Overall, 109 were women included. Spontaneous vaginal delivery and obstetric intervention were recorded in 40 (36.7%) and 69 (63.3%) patients, respectively. Spontaneous vaginal delivery was associated with a higher rate of occiput anterior position (90% vs 53.2%, P < .0001), lower head-perineum distance and head-symphysis distance (33.2 ± 7.8 mm vs 40.1 ± 9.5 mm, P = .001, and 13.1 ± 4.6 mm vs 19.5 ± 8.4 mm, P < .001, respectively), narrower midline angle (29.6° ± 15.3° vs 54.2° ± 23.6°, P < .001) and wider angle of progression at the acme of the pushing effort (153.3° ± 19.8° vs 141.8° ± 25.7°, P = .02) and delta-angle of progression (17.3° ± 12.9° vs 12.5° ± 11.0°, P = .04). At logistic regression analysis, only the midline angle and the head-symphysis distance proved to be independent predictors of spontaneous vaginal delivery. More specifically, the area under the curve for the prediction of spontaneous vaginal delivery was 0.80, 95% confidence interval (0.69-0.92), P < .001, and 0.74, 95% confidence interval (0.65-0.83), P = .002, for the midline angle and for the head-symphysis distance, respectively.

CONCLUSION

Transabdominal and transperineal intrapartum ultrasound parameters can predict the likelihood of spontaneous vaginal delivery in nulliparous women with prolonged second stage of labor.

Relationship between the Duration of the Second Stage of Labour and Neonatal Morbidity

(1) Background: To assess the relationship between the duration of the second stage of labour and the neonatal morbidity risk; (2) Methods: An observational, analytical, retrospective cohort study was performed at the "Mancha-Centro" Hospital (Spain) during the 2013⁻2016 period. Data were collected from 3863 women who gave a vaginal birth. The studied neonatal morbidity variables were umbilical cord arterial pH, 5-min Apgar score, need for advanced neonatal resuscitation, and a composite neonatal morbidity variable on which the multivariate analysis was done. A univariate analysis was used for the potential risk factors and a multivariate analysis with binary logistic regression to control for possible confounding factors; (3) Results: The univariate analysis showed a statistically significant relationship between the duration of the second stage of labour and a high risk of advanced neonatal resuscitation and composite neonatal morbidity in multiparous women. However, after performing the multivariate analysis for the variable "composite neonatal morbidity", we observed no relationship with the duration of the second stage of labour in either nulliparous or multiparous women; (4) Conclusions: The duration of the second stage of labour was not related to an increased risk of neonatal morbidity in our study population.

Operator experience affects the risk of obstetric anal sphincter injury in vacuum extraction deliveries

INTRODUCTION

Delivery by vacuum extraction is a major risk factor for obstetric anal sphincter injury. The aim of this study was to assess risk factors for obstetric anal sphincter injury in vacuum extraction in nulliparous women, specifically operator-related factors. A secondary aim was to assess other complications of vacuum extraction that are dependent on operator experience.

MATERIAL AND METHODS

A historical cohort study of nulliparous women with a live single fetus ≥34 weeks, delivered by vacuum extraction at a teaching hospital in Sweden in 1 year (2013), using data from medical records. Risk of obstetric anal sphincter injury was assessed for obstetricians (reference), gynecologists, and residents, and adjusted for maternal, fetal, procedure-related, and operator-related covariates using unconditional logistic regression. Results are presented as prevalence and crude and adjusted odds ratio (aOR) with 95% CI.

RESULTS

In total, 323 nulliparous women delivered by vacuum extraction were included. Obstetric anal sphincter injury occurred in 57 (17.6%) women. Fifteen (11.5%) obstetric anal sphincter injuries occurred in vacuum extractions performed by obstetricians, 10 (13.5%) by gynecologists (aOR 1.84, 95% CI 0.72-4.70), and 32 (26.9%) by residents (aOR 5.13, 95% CI 2.20-11.95). Maternal height ≤155 cm (aOR 4.63, 95% CI 1.35-15.9) and conversion to forceps (aOR 19.4, 95% CI 1.50-252) increased the risk of obstetric anal sphincter injury. Operator gender, night shift work, or being a frequent operator did not affect the risk of obstetric anal sphincter injury. Postpartum hemorrhage and fetal complications did not differ between operator categories.

CONCLUSIONS

The adjusted risk of obstetric anal sphincter injury in nulliparous women was five times higher in vacuum extractions performed by residents compared with those performed by obstetricians. Vacuum extractions performed by gynecologists did not carry an increased risk of obstetric anal sphincter injury. Experience in years of training, rather than frequency of the procedure, seemed to have the highest impact on reducing obstetric anal sphincter injury in vacuum extractions, which indicates a need for increased training and supervision.

Effect of Immediate vs Delayed Pushing on Rates of Spontaneous Vaginal Delivery Among Nulliparous Women Receiving Neuraxial Analgesia: A Randomized Clinical Trial

IMPORTANCE

It is unclear whether the timing of second stage pushing efforts affects spontaneous vaginal delivery rates and reduces morbidities.

OBJECTIVE

To evaluate whether immediate or delayed pushing results in higher rates of spontaneous vaginal delivery and lower rates of maternal and neonatal morbidities.

DESIGN, SETTING, AND PARTICIPANTS

Pragmatic randomized clinical trial of nulliparous women at or beyond 37 weeks' gestation admitted for spontaneous or induced labor with neuraxial analgesia between May 2014 and December 2017 at 6 US medical centers. The interim analysis suggested futility for the primary outcome and recruitment was terminated with 2414 of 3184 planned participants. Follow-up ended January 4, 2018.

INTERVENTIONS

Randomization occurred when participants reached complete cervical dilation. Immediate group participants (n = 1200) began pushing immediately. Delayed group participants (n = 1204) were instructed to wait 60 minutes.

MAIN OUTCOMES AND MEASURES

The primary outcome was spontaneous vaginal delivery. Secondary outcomes included total duration of the second stage, duration of active pushing, operative vaginal delivery, cesarean delivery, postpartum hemorrhage, chorioamnionitis, endometritis, perineal lacerations (≥second degree), and a composite outcome of neonatal morbidity that included neonatal death and 9 other adverse outcomes.

RESULTS

Among 2414 women randomized (mean age, 26.5 years), 2404 (99.6%) completed the trial. The rate of spontaneous vaginal delivery was 85.9% in the immediate group vs 86.5% in the delayed group, and was not significantly different (absolute difference, -0.6% [95% CI, -3.4% to 2.1%]; relative risk, 0.99 [95% CI, 0.96 to 1.03]). There was no significant difference in 5 of the 9 prespecified secondary outcomes reported, including the composite outcome of neonatal morbidity (7.3% for the immediate group vs 8.9% for the delayed group; between-group difference, -1.6% [95% CI, -3.8% to 0.5%]) and perineal lacerations (45.9% vs 46.4%, respectively; between-group difference, -0.4% [95% CI, -4.4% to 3.6%]). The immediate group had significantly shorter mean duration of the second stage compared with the delayed group (102.4 vs 134.2 minutes, respectively; mean difference, -31.8 minutes [95% CI, -36.7 to -26.9], P < .001), despite a significantly longer mean duration of active pushing (83.7 vs 74.5 minutes; mean difference, 9.2 minutes [95% CI, 5.8 to 12.6], P < .001), lower rates of chorioamnionitis (6.7% vs 9.1%; between-group difference, -2.5% [95% CI, -4.6% to -0.3%], P = .005), and fewer postpartum hemorrhages (2.3% vs 4.0%; between-group difference, -1.7% [95% CI, -3.1% to -0.4%], P = .03).

CONCLUSIONS AND RELEVANCE

Among nulliparous women receiving neuraxial anesthesia, the timing of second stage pushing efforts did not affect the rate of spontaneous vaginal delivery. These findings may help inform decisions about the preferred timing of second stage pushing efforts, when considered with other maternal and neonatal outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02137200.

Associations between improved care during the second stage of labour and maternal and neonatal health outcomes in a rural hospital in Bangladesh

OBJECTIVE

To evaluate the efficacy of care in the second stage of labour with a package of interventions that included (1) maintaining the birthing position according to the woman's choice, (2) adopting a spontaneous pushing technique and (3) using a support person, to reduce maternal and neonatal complications.

DESIGN

Used the data collected from two cohorts- before and after an initiative to improve care during the second stage of labour.

SETTING

A rural hospital in Bangladesh where 90-100 deliveries are conducted monthly and cesarean section provision is not available.

PARTICIPANTS

One thousand and fifty-one singleton pregnancies who attended the hospital for giving birth in the first stage of labour before full dilatation of the cervix and with cephalic presentation.

MEASUREMENTS AND FINDINGS

Data were collected through a structured checklist and questionnaire completed by research assistants; and also retrieved from hospital case record files, and the ongoing demographic surveillance system database. Coverage of adopting the upright or lateral position in the post-intervention period increased to 76% from about 1% in the pre-intervention period, and the spontaneous pushing technique increased to 97% from 77% in the same period. The odds of combined maternal and neonatal complications decreased by 46% between pre- and post-intervention periods (odds ratio: 0.54, 95% confidence interval: 0.43-0.70). Frequency of episiotomy (from 43% to 29%, P < 0.001), cervical tear (3.8% to 1.5%, P = 0.02), and median blood loss (200 ml to 150 ml; P < 0.001) were reduced significantly in the same period. No significant associations were observed in perineal tear or birth asphyxia occurrences.

KEY CONCLUSIONS AND IMPLICATIONS FOR PRACTICE

The study suggests that there is a beneficial effect of care during the second stage of labour with a package of interventions in reducing maternal and neonatal complications, particularly in reducing the frequency of episiotomy, cervical tear, and blood loss during delivery. The preferred choice of posture during giving birth, adopting a spontaneous pushing technique and continuous presence of support person during the second stage of labour may be encouraged for better health outcomes.

Factors associated with obstetric anal sphincter injuries in midwife-led birth: A cross sectional study

INTRODUCTION

Obstetric anal sphincter injurie (OASI) in vaginal births are a serious complication, and are associated with maternal morbidity. Focus on modifiable factors in midwives clinical skills and competences contributing to prevent the occurrence of OASI are essential. The objective of this study was to investigate the association between OASI and factors related to midwife-led birth such as manual support of perineum, active delivery of baby's shoulders, maternal birth position, and pushing and breathing techniques in second stage of labour.

METHODS

A prospective cross sectional study including primiparous (n = 129) and multiparous (n = 628) women in midwife-led non-instrumental deliveries with OASI (n = 96) or intact perineum (n = 661). Data were collected in a university hospital in Norway with two different birth settings: an alongside midwife-led unit with approximately 1500 births per year and an obstetrical unit with approximately 3500 births per year. In midwife-led births, there were a total of 2.6% OASI and 18.9% intact perineum.

RESULTS

The sample consisted of 757 women, 12.7% suffered OASI and 87.3% of participating women had an intact perineum. This selected sample compares the most serious outcome (OASI), and the optimal outcome (intact perineum).In primiparous women, 61 women suffered OASI and 68 women had intact perineum, while for multipara women, 35 women suffered OASI and 593 women had intact perineum. There was an increased risk of OASI if women actively pushed when the head was crowning compared to breathing the head out (adjusted OR: 3.10; 95% CI: 1.75 to 5.47). The maternal birth position associated with the lowest risk of OASI was kneeling position (adjusted OR: 0.15; 95% CI: 0.03 to 0.70), supine maternal birth position (adjusted OR: 2.52; 95% CI: 1.04 to 4.90) and oxytocin augmentation more than 30 min in second stage (OR: 1.93; 95% CI: 1.68 to 15.63) were associated with an increased risk of OASI, when adjusting for maternal, foetal, and obstetric factors.

CONCLUSION

Our study suggests that actively pushing when the baby's head is crowning, a supine maternal birth position and oxytocin augmentation more than 30 min in second stage, were associated with increased risk of OASI when compared to intact perineum. A kneeling maternal birth position was associated with a decreased risk of OASI.

Odon device for instrumental vaginal deliveries: results of a medical device pilot clinical study

Background

A prolonged and complicated second stage of labour is associated with serious perinatal complications. The Odon device is an innovation intended to perform instrumental vaginal delivery presently under development. We present an evaluation of the feasibility and safety of delivery with early prototypes of this device from an early terminated clinical study.

Methods

Hospital-based, multi-phased, open-label, pilot clinical study with no control group in tertiary hospitals in Argentina and South Africa. Multiparous and nulliparous women, with uncomplicated singleton pregnancies, were enrolled during the third trimester of pregnancy. Delivery with Odon device was attempted under non-emergency conditions during the second stage of labour. The feasibility outcome was delivery with the Odon device defined as successful expulsion of the fetal head after one-time application of the device.

Results

Of the 49 women enrolled, the Odon device was inserted successfully in 46 (93%), and successful Odon device delivery as defined above was achieved in 35 (71%) women. Vaginal, first and second degree perineal tears occurred in 29 (59%) women. Four women had cervical tears. No third or fourth degree perineal tears were observed. All neonates were born alive and vigorous. No adverse maternal or infant outcomes were observed at 6-weeks follow-up for all dyads, and at 1 year for the first 30 dyads.

Conclusions

Delivery using the Odon device is feasible. Observed genital tears could be due to the device or the process of delivery and assessment bias. Evaluating the effectiveness and safety of the further developed prototype of the BD Odon Device™ will require a randomized-controlled trial.

Trial registration

ANZCTR ACTRN12613000141741 Registered 06 February 2013. Retrospectively registered.

Viscous effects in pelvic floor muscles during childbirth: A numerical study

During vaginal delivery, women sustain stretching of their pelvic floor, risking tissue injury and adverse outcomes. Realistic numerical simulations of childbirth can help in the understanding of the pelvic floor mechanics and on the prevention of related disorders. In previous studies, biomechanical finite element simulations of a vaginal delivery have been performed disregarding the viscous effects present on all biological soft tissues. The inclusion of the viscoelastic behaviour is fundamental, since it allows to investigate rate-dependent responses. The present work uses a viscohyperelastic constitutive model to evaluate how the childbirth duration affects the efforts sustained by the pelvic floor during delivery. It was concluded that viscoelasticity adds a stiffness component that leads to higher forces comparing with the elastic response. Viscous solutions are rate dependent, and precipitous labours could be associated to higher efforts, while lower reaction forces were denoted for normal and prolonged labours, respectively. The existence of resting stages during labour demonstrated the capability of the tissue to relax and recover some of the initial properties, which helped to lower the forces and stresses involved. The present work represents a step further in achieving a robust non-invasive procedure, allowing to estimate how obstetrical factors influence labour and its outcomes.

Relationship between duration of second stage of labour and postpartum anaemia

AIM

To assess the relationship between the duration of the second stage of labour and postpartum anaemia during vaginal birth.

METHODS

An observational, analytical retrospective cohort study was performed at the "Mancha-Centro Hospital" (Spain) during the 2013-2016 period. Data were collected from 3437 women who had a vaginal birth. Postpartum anaemia was defined as a haemoglobin level below 11g/dL at 24h postpartum. A univariate analysis was used for potential risk factors and a multivariate analysis with binary logistic regression to control for possible confounding factors.

FINDINGS

The incidence of postpartum anaemia was 42.0%. The risk of postpartum anaemia did not increase in nulliparous women whose duration of the second stage of labour exceeded 4h. Compared with multiparous women who delivered between 0 and 3h, multiparous women with a duration of the second stage of labour beyond 3h were at higher risk of postpartum anaemia (OR=2.43 [1.30-4.52]).

CONCLUSION

The duration of the second stage of labour beyond 4h is safe for postpartum anaemia in nulliparous women. However in multiparous women, monitoring should increase if the second stage of labour exceeds 3h given the increased risk of postpartum anaemia.

A pilot randomised controlled trial exploring the effects of antenatal reflexology on labour outcomes

OBJECTIVE

to investigate the effects of antenatal reflexology on labour outcomes.

DESIGN

secondary analysis of a pilot three-armed randomised controlled trial conducted between July 2012 and September 2013.

SETTING

a large UK inner city hospital maternity department.

PARTICIPANTS

ninety primiparous women with a singleton pregnancy experiencing low back and / or pelvic girdle pain.

INTERVENTIONS

six weekly 30-minute reflexology treatments compared to sham (footbath) treatments or usual antenatal care only.

MEASUREMENTS

labour outcome data including labour onset, duration of the second stage of labour, epidural and Entonox usage, and mode of delivery. Participant feedback was collected prior to each treatment.

FINDINGS

labour outcomes were collected for 61 women (95.3%) who completed the study. The second stage of labour duration data, available for 42 women (62.5%) who had vaginal births, showed a mean reduction of 44minutes in the reflexology group (73.56minutes; SD= 53.78) compared to the usual care (117.92minutes; SD=56.15) (p<0.05) and footbath groups (117.4minutes; SD=68.54) (p=0.08). No adverse effects were reported.

KEY CONCLUSIONS

in this trial antenatal reflexology reduced labour duration for primiparous women who had experienced low back and/ or pelvic girdle pain during their pregnancy, compared with usual care and footbaths.

IMPLICATIONS FOR PRACTICE

reflexology is suitable for use during pregnancy, is safe and enjoyable and may reduce labour duration. Midwives may wish to recommend reflexology to promote normal childbirth and facilitate women centred care.

TRIAL REGISTRATION

this trial was listed with the International Standard Randomised Controlled Trial Number Register (ISRCTN26607527).

Duration of labor and the risk of severe postpartum hemorrhage: A case-control study

Objective

Our main objective was to investigate the association between duration of active labor and severe postpartum hemorrhage. We examined the effect of the total duration of active labor, the effect of each stage of active labor, and the gradient effect of duration of labor on severe postpartum hemorrhage.

Methods

A case-control study was generated from a source population of all women admitted for delivery at Oslo University Hospital and Drammen Hospital in Buskerud municipality during the time period January 1, 2008 to December 31, 2011. The study population included all cases of severe postpartum hemorrhage (n = 859) and a random sample of controls (n = 1755). Severe postpartum hemorrhage was defined as postpartum blood loss ≥1500 mL or need for blood transfusion. Prolonged labor was defined as duration of active labor >12 hours according to the definition of the World Health Organization. We used logistic multivariable regression in the analysis.

Results

We observed a significantly longer mean duration of labor in women who experienced severe postpartum hemorrhage compared to controls (5.4 versus 3.8 hours, p<0.001). Women with severe postpartum hemorrhage also had a longer duration of all stages of active labor compared to controls. The association between the duration of active labor and severe postpartum changed from a linear dose-response association to a threshold association after adjusting for augmentation with oxytocin, induction of labor, primiparity, and fever during labor. Compared to controls, women with severe postpartum hemorrhage were more likely to have a prolonged labor >12 hours (adjusted odds ratio = 2.44, 95% confidence interval: 1.69–3.53, p< 0.001).

Conclusion

Prolonged active labor (duration >12 hours) was associated with severe postpartum hemorrhage. Increased vigilance seems required when the labor is prolonged to reduce the risk of severe postpartum hemorrhage.

[Risks factors of cesarean delivery after 3hours of delayed pushing]

OBJECTIVES

Identify the factors associated with caesarean delivery for unengaged fetal head beyond 3hours of passive second stage of labor, among primiparous patients.

METHODS

A case-control study conducted in level III universitary center between October 2012 and September 2015. Only primiparous at term, with a singleton, cephalic fetus and a passive second stage of labor prolonged over 3hours before pushing were included. During the second stage of labor, patients who had caesarean for abnormal fetal heart rate were excluded. Risk factors of cesarean were analyzed with univariate analysis and after statistical adjustment using multivariate logistic regression.

RESULTS

The mean passive second stage duration was significantly longer among patients who had a caesarean (3h37±21min vs 3h13±19min [P=0,0001]). After multivariate logistic regression, factors associated with a risk of caesarean were body mass index higher than 30kg/m² (OR=25.9 [3.1-215.9]). fetal macrosomia suspected by 3rd trimester ultrasound (OR=4.4 [1.2-16.4]), induction by prostaglandins (OR=5.7 [2.1-15.5]), a stagnation of cervical dilatation during the 1st stage (OR=[1.3-6.8]), and fetal occiput posterior position beyond 3hours (OR=30.7 [3.3-280.9]).

CONCLUSIONS

Risk of caesarean delivery for unengaged fetal head beyond 3hours of passive second stage of labor is associated with maternal, fetal and obstetrical factors. Those factors might be taken into account before accept or not a 3rd hour at full cervical dilation.

Durations of second stage of labor and pushing, and adverse neonatal outcomes: a population-based cohort study

OBJECTIVE

The associations between duration of second stage of labor, pushing time and risk of adverse neonatal outcomes are not fully established. Therefore, we aimed to examine such relationships.

STUDY DESIGN

A population-based cohort study including 42 539 nulliparous women with singleton infants born in cephalic presentation at ⩾37 gestational weeks, using the Stockholm-Gotland Obstetric Cohort, Sweden, and the Swedish Neonatal Quality Register, 2008 to 2013. Poisson regression was used to analyze estimated adjusted relative risks (RRs), with 95% confidence intervals (CIs). Outcome measures were umbilical artery acidosis (pH <7.05 and base excess <-12), birth asphyxia-related complications (including any of the following conditions: hypoxic ischemic encephalopathy, hypothermia treatment, neonatal seizures, meconium aspiration syndrome or advanced resuscitation after birth) and admission to neonatal intensive care unit (NICU).

RESULTS

Overall rates of umbilical artery acidosis, birth asphyxia-related complications and admission to NICU were 1.08, 0.63 and 6.42%, respectively. Rate of birth asphyxia-related complications gradually increased with duration of second stage: from 0.42% at <1 h to 1.29% at ≥4 h (adjusted RR 2.46 (95% CI 1.66 to 3.66)). For admission to NICU, corresponding rates were 4.97 and 9.45%, and adjusted RR (95% CI) was 1.80 (95% CI 1.58 to 2.04). Compared with duration of pushing <15 min, a duration of pushing ⩾60 min increased rates of acidosis from 0.57 to 1.69% (adjusted RR 2.55 (95% CI 1.51 to 4.30)).

CONCLUSION

Prolonged durations of second stage of labor and pushing are associated with increased RRs of adverse neonatal outcomes. Clinical assessment of fetal well-being is essential when durations of second stage and pushing increases.

Duration of Second Stage of Labour at Term and Pushing Time: Risk Factors for Postpartum Haemorrhage

BACKGROUND

Prolonged labour is associated with increased risk of postpartum haemorrhage (PPH), but the role of active pushing time and the relation with management during labour remains poorly understood.

METHODS

A population-based cohort study from electronic medical record data in the Stockholm-Gotland Region, Sweden. We included 57 267 primiparous women with singleton, term gestation, livebirths delivered vaginally in cephalic presentation in 2008-14. We performed multivariable Poisson regression to estimate the association between length of second stage, pushing time, and PPH (estimated blood loss >500 mL during delivery), adjusting for maternal, delivery, and fetal characteristics as potential confounders.

RESULTS

The incidence of PPH was 28.9%. The risk of PPH increased with each passing hour of second stage: compared with a second stage <1 h, the adjusted relative risk (RR) for PPH were for 1 to <2 h 1.10 (95% confidence interval (CI) 1.07, 1.14); for 2 to <3 h 1.15 (95% CI 1.10, 1.20); for 3 to <4 h 1.28 (95% CI 1.22, 1.33); and for ≥4 h 1.40 (95% CI 1.33, 1.46). PPH also increased with pushing time exceeding 30 min. Compared to pushing time between 15 and 29 min, the RR for PPH were for <15 min 0.98 (95% CI 0.94, 1.03); for 30-44 min 1.08 (95% CI 1.04, 1.12); for 45-59 min 1.11 (95% CI 1.06, 1.16); and for ≥60 min 1.20 (95% CI 1.15, 1.25).

CONCLUSIONS

Increased length of second stage and pushing time during labour are both associated with increased risk of PPH.

Duration of second stage of labor and instrumental delivery as risk factors for severe perineal lacerations: population-based study

Background

We sought to investigate the impact of the duration of second stage of labor on risk of severe perineal lacerations (third and fourth degree).

Methods

This population based cohort study was conducted in the Stockholm/Gotland region, Sweden, 2008–2014. Study population included 52 211 primiparous women undergoing vaginal delivery with cephalic presentation at term. Unconditional logistic regression analysis was used to calculate crude and adjusted odds ratios (OR), using 95% confidence intervals (CI). Main exposure was duration of second stage of labor, and main outcome was risks of severe perineal lacerations (third and fourth degree).

Results

Risk of severe perineal lacerations increased with duration of second stage of labor. Compared with a second stage of labor of 1 h or less, women with a second stage of more than 2 h had an increased risk (aOR 1.42; 95% CI 1.28–1.58). Compared with non-instrumental vaginal deliveries, the risk was elevated among instrumental vaginal deliveries (aOR 2.24; 95% CI 2.07–2.42). The risk of perineal laceration increased with duration of second stage of labor until less than 3 h in both instrumental and non-instrumental vaginal deliveries, but after 3 h, the ORs did not further increase. After adjustments for potential confounders, macrosomia (birth weight > 4 500 g) and occiput posterior fetal position were risk factors of severe perineal lacerations.

Conclusions

The risk of severe perineal laceration increases with duration until the third hour of second stage of labor. Instrumental delivery is the most significant risk factor for severe lacerations, followed by duration of second stage of labor, fetal size and occiput posterior fetal position.

Risk factors for serious morbidity in term nonanomalous neonates

OBJECTIVE

The purpose of this study was to identify ante- and intrapartum risk factors for serious morbidity in term nonanomalous neonates.

STUDY DESIGN

We analyzed the first 5000 subjects within an ongoing prospective cohort study of consecutive term births from 2010-2012. The primary outcome was a composite of serious neonatal morbidity defined as ≥1 cases of hypoxic ischemic encephalopathy, meconium aspiration with pulmonary hypertension, requirement of hypothermia therapy, respiratory distress syndrome, seizures, sepsis or suspected sepsis, or death. We calculated odds ratios for the composite morbidity that is associated with ante- and intrapartum factors. Multivariable logistic regression was used to estimate adjusted odds ratios.

RESULTS

Of 5000 term nonanomalous births, 393 had the composite morbidity. Significant risk factors for morbidity were nulliparity, presence of meconium, first stage of labor >95th percentile, second stage of labor >95th percentile, pregestational diabetes mellitus, chronic hypertension, obesity, maternal intrapartum fever, and cesarean delivery. In contrast, induction of labor and gestational age ≥41 weeks were not associated with significant morbidity.

CONCLUSION

We identified several significant risk factors for serious morbidity in term nonanomalous neonates. Clinicians may use these risk factors to help anticipate the potential need for additional neonatal support at delivery.