Anovaginal distance and obstetric anal sphincter injury: a prospective observational study

Birth and Regulation of head Extension to Guide Manual perineal Assistance (BREGMA) study: a prospective cohort study

BACKGROUND

The exact positioning of the dominant hand at the time of manual perineal protection (MPP) is not clearly specified. The main aim of this work was to identify the place on the perineum where pressure needs to be applied to achieve optimal forward fetal head displacement away from the anal sphincters using the bregma to posterior fourchette distance (BFD) and the perineal body length (PBL).

METHODS

This was a two-center prospective cohort study. Term cephalic singleton nulliparous women having spontaneous vaginal delivery were considered eligible for recruitment into the study. Once crowning was diagnosed and just prior the initiation of manual perineal protection (MPP) or cutting an episiotomy, the BFD and PBL were measured using a standardized measurement protocol.

RESULTS AND DISCUSSION

A total of 100 women (50 women in each center) were recruited into the study. The overall mean BFD was 2.8 ± 0.5 cm. The overall mean PBL was 4.4 ± 0.8 cm. There were no statistically significant differences between the measurements taken in both units regarding BFD or PBL (p = 0.81 and 0.10 respectively). There was a weak correlation between both measurements. Based on our measured parameters, it seems that the most effective point to apply perineal pressure to displace the head away from the anus is approximately 1 - 1.5 cm anterior to the anal margin.

CONCLUSION

Measurements generated by this study will form the bases of future biomechanical studies to confirm their validity.

Subclassification of second-degree tears at delivery: creation and reported outcomes

BACKGROUND

Perineal tears at delivery are common. The current WHO classification system compacts all the varying extents of second-degree tears into one code. Some tears lead to long-term injuries. The correct identification and classification of disease is necessary for correct clinical management as well as for research. Regulatory standards govern care practices. This article describes the process of creating and testing new subclassifications for second-degree tears at delivery.

METHODS

The development and implementation of new subclassifications of second-degree perineal tears after delivery in Sweden are described. The new classification was tested for incidence and relevance via the national perineal laceration register (PLR) in 11,203 women with prospectively recorded second degree tears.

RESULTS

Second-degree tears after delivery are subdivided into four subgroups according to the anovaginal distance and the extent in length and depth of the largest perineal/vaginal tear, which can be combined with uni-or bilateral levator ani avulsion. Women with larger second-degree tears were more likely than women with smaller tears to report complications after eight weeks (OR 1.41 CI 1.21-1.64, p < 0.001) and one year (OR 1.27, CI 1.1-1.46, p < 0.001).

CONCLUSION

Detailed subclassifications of perineal and vaginal tears are implemented in the Swedish ICD-10 coding system and Swedish national registers. The outcomes after second-degree tears differ according to their extent, which corroborates the classification rationale. These subclassifications can be used in studies of preventive measures, treatment and patient-reported outcomes and experiences taking into account the extent of second-degree perineal tears at delivery.

TRIAL REGISTRATION

Data regarding women were prospectively collected from the National perineal laceration register (PLR) from January 1, 2021, to December 31, 2022.

2D-transperineal ultrasound in delivery room: Contribution in assessing labor progress, predicting outcome of labor and recognizing obstetric anal sphincter injuries (OASIS). A systematic review

AIMS

Ultrasound is used in the delivery room to assess fetal head position, engagement during labor, and anal sphincter injuries in the immediate postpartum period. The transperineal approach allows for direct visualization of the structures of interest without altering anatomical landmarks. Various ultrasound measurements during labor have been described in the literature, and their use varies widely across maternity units. Our objective was to conduct a systematic review of the literature on relevant ultrasound parameters for the management of labor and delivery.

MATERIAL AND METHODS

We reviewed articles indexed in MEDLINE from 1990 to 2022, selecting those that evaluated transperineal ultrasound during labor for term singleton fetuses in cephalic presentation.

RESULTS

We identified 124 articles out of 394 references, including 4 randomized controlled trials, 108 prospective studies, 6 cross-sectional studies, and 6 retrospective studies. The Angle of Progression (AOP) is better documented and appears more reliable than the Head-Perineum Distance (HPD) for diagnosing engagement, monitoring labor, and predicting its outcome. The HPD is easier to perform but shows inconsistencies in the literature. The Head Progression Distance (HPrD) shows good performance but requires further studies before routine use, as does Head-Symphysis Distance (HSD). Recent studies show a growing interest in ultrasound biofeedback of fetal head progression to improve pushing efforts as well as screening for Obstetrical Anal Sphincter Injuries (OASIS).

CONCLUSIONS

Transperineal ultrasound is a minimally invasive technique that can be used routinely in the delivery room. It can aid in monitoring labor, predicting the mode of delivery, and may serve as valuable biofeedback to optimize pushing during expulsion.

Antenatal Anovaginal Distance, a Potential Indicator of Perineal Damage during Pregnancy

BACKGROUND/OBJECTIVES

Perineal injuries, including episiotomies and spontaneous tears, are common complications during childbirth, often leading to significant discomfort and prolonged recovery for women. This retrospective observational cohort study aimed to explore the relationship between antenatal anovaginal distance (AVD) and the incidence of perineal injuries in a cohort of pregnant women evaluated for pelvic floor health at 28 to 32 weeks of gestation.

METHODS

Conducted at the University Hospital of Padua over 18 months, the study included 416 women who underwent vaginal delivery at term. Based on AVD, the study participants were divided into two groups: AVD-N group, which included 252 patients with AVD ≥ 2 cm, and the AVD-R group, which included 164 with AVD < 2 cm. The results of the pelvic floor assessment and those related to childbirth were then examined in relation to AVD (reduced vs. normal).

RESULTS

The study found that women with reduced AVD were more likely to experience perineal injuries. Specifically, the incidence of episiotomy and severe perineal tears (3rd and 4th degree) was significantly higher in the reduced AVD group (p < 0.05). Furthermore, a lower AVD was associated with increased perineal muscle hypertonicity and a higher likelihood of operative delivery with episiotomy. Logistic regression analysis confirmed that reduced AVD was an independent risk factor for perineal injuries, regardless of other maternal or neonatal characteristics.

CONCLUSIONS

These results suggest that AVD measurement during pregnancy may help identify women at higher risk of perineal trauma, enabling more personalized obstetric care to mitigate these outcomes.

Occurrence and risk factors for second-degree perineal tears: A prospective cohort study using a detailed classification system

BACKGROUND

The amount of tissue trauma within second-degree perineal tears varies widely. Therefore, subcategorization of second-degree tears and a better understanding of their occurrence and risk factors are needed. The aim of this study was to assess the occurrence of perineal tears when second-degree tears were subcategorized. Furthermore, we aimed to assess the association between variables related to perineal anatomy and other potential risk factors, with second-degree tear subcategories.

METHODS

This prospective cohort study included 880 primiparous and multiparous women giving birth to one child vaginally. Perineal tears were categorized using the classification system recommended by the Royal College of Obstetricians and Gynaecologists. In addition, second-degree tears were subcategorized as 2A, 2B, or 2C according to the percentage of damage to the perineal body. Selected variables related to perineal anatomy were as follows: length of genital hiatus; perineal body length; and previous perineal trauma. Risk factors for second-degree tear subcategories were analyzed using a multinominal regression model.

RESULTS

Perineal tears occurred as follows: first-degree: 35.6% (n = 313), 2A: 16.3% (n = 143), 2B: 9.1% (n = 80), 2C: 6.6% (n = 58), and third- or fourth-degree: 1.6% (n = 14). In total, 169/880 participants underwent an episiotomy. When episiotomies were excluded, the risk for 2B, or 2C tears increased with smaller genital hiatus, larger perineal body, previous perineal trauma, primiparity, higher gestational age, instrumental vaginal delivery and fetal presentation other than occiput anterior.

CONCLUSION

The occurrence of second-degree tear subcategories was 16.3% for 2A tears, 9.1% for 2B tears, and 6.6% for 2C tears. Factors related to perineal anatomy increased the odds for experiencing a second-degree tear in a more severe subcategory.

Sonographic postpartum anal sphincter defects and the association with pelvic floor pain and dyspareunia

INTRODUCTION

Pelvic floor pain and dyspareunia are both important entities of postpartum pelvic pain, often concomitant and associated with perineal tears during vaginal delivery. The association between postpartum sonographic anal sphincter defects, pelvic floor pain, and dyspareunia has not been fully established. We aimed to determine the prevalence of postpartum anal sphincter defects using three-dimensional endoanal ultrasonography (3D-EAUS) and evaluate their association with symptoms of pelvic floor pain and dyspareunia.

MATERIAL AND METHODS

This prospective cohort study followed 239 primiparas from birth to 12 months post delivery. Anal sphincters were assessed with 3D-EAUS 3 months postpartum, and self-reported pelvic floor function data were obtained using a web-based questionnaire distributed 1 year after delivery. Descriptive statistics were compared between the patients with and without sonographic defects, and the association between sonographic sphincter defects and outcomes were analyzed using logistic regression.

RESULTS

At 3 months postpartum, 48/239 (20%) patients had anal sphincter defects on 3D-EAUS, of which 43 (18%) were not clinically diagnosed with obstetric anal sphincter injury at the time of delivery. Patients with sonographic defects had higher fetal weight than those without defects, and a perineum <2 cm before the suture was a risk factor for defects (odds ratio [OR], 6.9). Patients with sonographic defects had a higher frequency of dyspareunia (OR, 2.4), and pelvic floor pain (OR, 2.3) than those without defects.

CONCLUSIONS

Our results suggest an association between postpartum sonographic anal sphincter defects, pelvic floor pain, and dyspareunia. A perineal height <2 cm, measured by bidigital palpation immediately postdelivery, was a risk factor for sonographic anal sphincter defect. We suggest offering pelvic floor sonography around 3 months postpartum to high- risk women to optimize diagnosis and treatment of perineal tears and include perineum <2 cm prior to primary repair as a proposed indication for postpartum follow-up sonography.

The effect of organizational belonging and profession on clinicians' attitudes toward supporting vaginal birth and interprofessional teamwork-a cross-sectional study

INTRODUCTION

The aim of this study was to investigate the effect of organizational belonging and profession on clinicians' attitudes toward supporting vaginal birth and interprofessional teamwork in Swedish maternity care.

MATERIAL AND METHODS

The study used a cross-sectional design, with a web-based survey sent to midwives, physicians and nurse assistants at five labor wards in Sweden. The survey consisted of two validated scales: the Swedish version of the Labor Culture Survey (S-LCS), measuring attitudes toward supporting vaginal birth, and the Assessment of Collaborative Environments (ACE-15), measuring attitudes toward interprofessional teamwork. Two-way ANOVA was conducted to assess the main effect of and interaction effect between organizational belonging and profession for the different subscales of the S-LCS and the ACE-15, together with Tukey's honest significant difference post-hoc analysis and partial eta squared to determine effect size. The relation between the subscales was assessed using the Pearson's correlation analysis.

RESULTS

A total of 539 midwives, physicians and nurse assistants completed the survey. Organizational belonging significantly influenced attitudes toward supporting vaginal birth and interprofessional teamwork, with the largest effect for Positive team culture (F = 38.88, effect size = 0.25, p < 0.001). The effect of profession was strongest for the subscale Best practices (F = 59.43, effect size = 0.20, p < 0.001), with midwives being more supportive of strategies proposed to support vaginal birth than physicians and nurse assistants. A significant interaction effect was found for four of the subscales of the S-LCS, with the strongest effect for items reflecting the Unpredictability of vaginal birth (F = 4.49, effect size = 0.07, p < 0.001). Labor ward culture (unit microculture) specifically related to supporting vaginal birth was strongly correlated to interprofessional teamwork (r = 0.598, p < 0.001).

CONCLUSIONS

In the current study, both organizational belonging and profession influenced attitudes toward supporting vaginal birth and interprofessional teamwork. Positive team culture was positively correlated to an organizational culture supportive of vaginal birth. Interventions to support vaginal births should include efforts to strengthen teamwork between professions, as well as considering women's values, preferences and informed choices.

One Plus One Equals Two-will that do? A trial protocol for a Swedish multicentre randomised controlled trial to evaluate a clinical practice to reduce severe perineal trauma {1}

Background

Severe perineal trauma sustained during childbirth is a serious complication since it can lead to both short- and long-term consequences for women. Some of the methods used to prevent perineal injuries have been evaluated in clinical trials, but there are still gaps in the evidence. A new clinical practice has been introduced, adopted by more than half of the maternity wards in Sweden with the aim of reducing severe perineal trauma. This procedure involves two midwives assisting the woman during the second stage of labour.

Methods/design

In this multicentre randomised controlled trial, 2946 women will be randomised to be assisted by one or two midwives during the second stage of labour. Women age 18–47, who plan for their first vaginal birth, with a singleton pregnancy in cephalic presentation, will be asked to participate when admitted to the maternity ward. Five maternity wards comprising 19,500 births/year in different parts of Sweden will participate in this study. The sample size is powered to demonstrate a 50% reduction (from 4.1–2.0%) in primary outcome, which is the prevalence of severe perineal trauma (3rd and 4th degree). Secondary outcomes will include maternal and neonatal outcomes, women’s experiences, midwives’ experiences of the intervention, incontinence, and pelvic floor symptoms. The primary analysis is intention to treat. Questionnaires will be sent to the women at 1 month and 1 year after the birth to assess women’s experiences, pain, incontinence, pelvic floor symptoms, sexual function, and mental health.

Discussion

It is important for care during labour and birth to be evidence based. There is a strong desire among midwives to reduce the risk of severe perineal trauma. This may lead to new strategies and practices being implemented into practice without scientific evidence. The intervention might have negative side effects or unintended consequences. On the other hand, there is a possibility of the intervention improving care for women.

Trial registration {2a}

ClinicalTrials.gov NCT03770962. Registered on 10 December 2018