Risk factors for severe perineal lacerations during childbirth

Adjusting models to better predict obstetric anal sphincter injury (OASIS) in forceps-assisted vaginal deliveries: A retrospective cross-sectional trial

OBJECTIVE

Obesity and maternal age are increasing among pregnant patients. The understood effect of body mass index (BMI), advanced maternal age (AMA), and second stage of labor on obstetric anal sphincter injury (OASIS) at delivery is varied. The objective of this study was to assess whether incorporating BMI, second stage of labor length, and AMA into a model for predicting OASIS among forceps-assisted vaginal deliveries (FAVD) had a higher predictivity value compared to models without these additions.

METHOD

This was an IRB-approved retrospective cohort study of singleton gestations who underwent a FAVD between 2017 and 2021. The primary outcome was prediction of OASIS via established models versus models including the addition of new predictive factors.

RESULTS

A total of 979 patients met inclusionary criteria and were included in the final analysis. 20.4% of patients had an OASIS laceration, 11.3% of neonates had NICU admissions, 23.7% had a composite all neonatal outcome, and 8% had a composite subgaleal/cephalohematoma outcome. Comparisons of known factors that predict OASIS (nulliparity, race, episiotomy status) to known factors with additional predictors (BMI, AMA, and length of second stage in labor) were explored. After comparing each model's AUC to one another (a total of 3 comparisons made), there was no statistically significant difference between the models (all P > 0.62).

CONCLUSION

Including BMI, AMA, and second stage of labor length does not improve the predictivity of OASIS in patients with successful FAVD. These factors should not impact a provider's decision to perform a FAVD when solely considering increased odds of OASIS.

Obstetric Anal Sphincter Injury Care Bundle: A Quality Improvement Initiative

INTRODUCTION AND HYPOTHESIS

The objective was to implement an evidence-based peri-partum care bundle for women sustaining obstetric anal sphincter injuries and to evaluate compliance with recommendations for antibiotics use, repair in the operating room, and follow-up before and after implementation.

METHODS

This project was reviewed by the Institutional Review Board and determined to be exempt. A clinical care bundle containing education and standardized orders in the electronic medical record was implemented. Characteristics of pre- (October 2017 to September 2019) and post-intervention (October 2019 to August 2021) cohorts were compared and compliance with recommendations for antibiotics use, surgical repair location, and follow-up were evaluated. Chi-squared, Fisher's exact, ANOVA F, and Kruskal-Wallis tests were performed, as indicated. Significance level was p < 0.05.

RESULTS

A total of 185 cases were identified. Seventy-five percent of women were nulliparous. Mean gestational age was 39 weeks. Pre- and post-intervention groups did not differ in age, BMI, race, parity, gestational age, comorbidities, birthweight, or delivery type. Ninety-eight cases were identified pre-implementation. Eighty-six (88%) had third-degree lacerations. Post-implementation, 87 cases were identified. Seventy (80%) had third-degree lacerations (p = 0.17). Recommended antibiotic-type use improved from 35% pre-implementation to 93% post-implementation (p < 0.001). Repair in the operating room was similar pre-implementation and post-implementation (16.0% vs 12.6%, p = 0.48). Post-partum follow-up within 2 weeks improved from 16.3% pre-implementation to 52.8% post-implementation and mean time to follow-up was shorter post-implementation than pre-implementation (18 vs 33 days; both p < 0.001).

CONCLUSIONS

Implementation of an evidence-based peri-partum care bundle resulted in standardization of care in accordance with established recommendations. Compliance with recommendations for surgical repair in the operating room remained unchanged.

Trends and determinants of the use of episiotomy in a prospective population-based registry from central India

BACKGROUND

Findings from research and recommendations from the World Health Organization favor restrictive use of episiotomy, but whether this guidance is being followed in India, and factors associated with its use, are not known. This study sought to document trends in use of episiotomy over a five-year period (2014-2018); to examine its relationship to maternal, pregnancy, and health-system characteristics; and to investigate its association with other obstetric interventions.

METHODS

We conducted a secondary analysis of data collected by the Maternal Newborn Health Registry, a prospective population-based pregnancy registry established in Central India (Nagpur, Eastern Maharashtra). We examined type of birth and use of episiotomy in vaginal deliveries from 2014 to 2018, as well as maternal and birth characteristics, health systems factors, and concurrent obstetric interventions associations with its use with multivariable Poisson regression models.

RESULTS

During the five-year interval, the rate of episiotomy in vaginal birth rose from 13 to 31% despite a decline in assisted vaginal birth. Associations with episiotomy were found for the following factors: prior birth, multiple gestations, seven or more years of maternal education, higher gestational age, higher birthweight, delivery by an obstetrician (as compared to midwife or general physician), and birth in hospital (as compared to clinic or health center). After adjusting for these factors, year over year rise in episiotomy was significant with an adjusted incidence rate ratio (AIRR) of 1.10 [95% confidence interval (CI) 1.08-1.12; p = 0.002]. We found an association between episiotomy and several other obstetric interventions, with the strongest relationship for maternal treatment with antibiotics (AIRR 4.23, 95% CI 3.12-5.73; p = 0.001).

CONCLUSIONS

Episiotomy in this population-based sample from central India steadily rose from 2014 to 2018. This increase over time was observed even after adjusting for patient characteristics, obstetric risk factors, and health system features, such as specialty of the birthing provider. Our findings have important implications for maternal-child health and respectful maternity care given that most women prefer to avoid episiotomy; they also highlight a potential target for antibiotic stewardship as part of global efforts to combat antimicrobial resistance.

TRIAL REGISTRATION

The study was registered at ClinicalTrials.gov under reference number NCT01073475.

Severe perineal lacerations in induction of labor versus expectant management: A systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

This study aimed to evaluate if induction of labor (IOL) is associated with an increased risk of severe perineal laceration.

DATA SOURCES

A systematic search was conducted in MEDLINE, Ovid, Scopus, ClinicalTrials.gov, Cochrane Central Register of Controlled Trials, and CINHAL using a combination of keywords and text words related to "induction of labor," "severe perineal laceration," "third-degree laceration," "fourth-degree laceration," and "OASIS" from inception of each database until January 2023.

STUDY ELIGIBILITY CRITERIA

We included all randomized controlled trials (RCTs) comparing IOL to expectant management of a singleton, cephalic pregnancy at term gestation that reported rates of severe perineal laceration.

STUDY APPRAISAL AND SYNTHESIS AND METHODS

The primary outcome of interest was severe perineal laceration, defined as 3rd- or 4th-degree perineal lacerations. We conducted meta-analyses using the random effects model of DerSimonian and Laird to determine the relative risks (RR) or mean differences with 95% confidence intervals (CIs). Bias was assessed using guidelines established by Cochrane Handbook for Systematic Reviews of Interventions.

RESULTS

A total of 11,187 unique records were screened and ultimately eight RCTs were included, involving 13,297 patients. There was no statistically significant difference in the incidence of severe perineal lacerations between the IOL and expectant management groups (209/6655 [3.1%] vs 202/6641 [3.0%]; RR 1.03, 95% CI 0.85, 1.26). There was a statistically significant decrease in the rate of cesarean birth (1090/6655 [16.4%] vs 1230/6641 [18.5%], RR 0.89, 95% CI 0.82, 0.95) and fetal macrosomia (734/2696 [27.2%] vs 964/2703 [35.7%]; RR 0.67: 95% CI 0.50, 0.90) in the IOL group.

CONCLUSION

There is no significant difference in the risk of severe perineal lacerations between IOL and expectant management in this meta-analysis of RCTs. Furthermore, there is a lower rate of cesarean births in the IOL group, indicating more successful vaginal deliveries with similar rates of severe perineal lacerations. Patients should be counseled that in addition to the known benefits of induction, there is no increased risk of severe perineal lacerations.

In vivo measurement of the elastic properties of pelvic floor muscles in pregnancy using shear wave elastography

OBJECTIVE

We aimed to investigate changes in the elastic properties of levator ani muscle (LAM) and external anal sphincter (EAS) during pregnancy using shear wave elastography (SWE). Our secondary objective was to examine the association between the elastic properties of pelvic floor muscles (PFM) and perineal tears at childbirth.

METHODS

This was a prospective monocentric study, including nulliparous women. Three visits were planned (14-18, 24-28, and 34-38 weeks) with a SWE assessment of the LAM and EAS at rest and during Valsalva maneuver. Then, we collected data about the delivery's characteristics. Assessments were performed using an Aixplorer V12® device (SL 18-5 linear probe) using a transperineal approach, reporting the shear modulus in kPa. We looked for changes in PFM's elastic properties during pregnancy using one-way ANOVA for repeated measures. We compared the mean shear modulus in late pregnancy for each muscle and condition between women with an intact perineum at delivery and those with a perineal tear using Student's t test.

RESULTS

Forty-seven women were considered. Forty-five women had vaginal delivery of which 38 (84.4%) had perineal tears. We did not report any significant changes in the elastic properties of PFM during pregnancy. Women with an intact perineum at delivery had a stiffer EAS at Valsalva maneuver in late pregnancy (27.0 kPa vs. 18.2 kPa; p < 0.005).

CONCLUSIONS

There were no significant changes in the elastic properties of the PFM in pregnancy. Stiffer EAS in late pregnancy appears to be associated with a lower incidence of perineal tears.

Midwives' approach to the prevention and repair of obstetric perineal trauma in Spain

AIM

Different clinical practice guidelines include recommendations on how to prevent and repair obstetric perineal trauma, as well as the use of episiotomy. To evaluate the variability in midwives' professional practices for preventing and repairing perineal trauma, as well as the professional factors that may be associated with the restrictive use of episiotomy.

DESIGN

Observational cross-sectional study.

METHODS

Three hundred five midwives completed an anonymous questionnaire developed by the authors and distributed across various midwifery scientific societies. The main outcomes measured were the frequencies of adopting specific practices related to perineal injury prevention and repair, episiotomy technique and restrictive episiotomy use (<10%). Odds ratios (OR) and adjusted odds ratios (aOR) with 95% confidence intervals were estimated.

RESULTS

Intrapartum perineal massage was not normally used by 253 (83%) of midwives, and 186 (61%) applied compresses soaked in warm water to the perineum. Regarding episiotomy, there was a great deal of variability, noting that 129 (42.3%) adopted a restrictive use of this procedure, 125 (41%) performed it between 10% and 20%, while 51 midwives (16.7%) performed it in more than 20% of cases. In addition, 165 (54.1%) midwives followed an incision angle of 60º. Concerning tears, 155 (50.8%) usually sutured first-degree tears and 273 (89.5%) always sutured second-degree tears. Midwives attending home births (aOR = 6.5; 95% CI: 2.69-15.69), working at a teaching hospital (aOR = 3.69; 95% CI: 1.39-9.84), and the ones who recently completed their professional training (aOR = 3.58; 95% CI: 1.46-8.79) were significantly more likely to adopt a restrictive use of episiotomy.

CONCLUSIONS

There is a significant variability in Spanish midwives' practices for preventing and repairing perineal tears. Moreover, the restrictive use of episiotomy is associated with midwives attending home births, working in teaching hospitals and having recent professional training.

PATIENT OR PUBLIC CONTRIBUTION

No patient or public contribution.

Vacuum-assisted delivery outcomes: is advanced maternal age a factor?

PURPOSE

This study evaluated age-related maternal outcomes of vacuum-assisted vaginal deliveries (VAD).

METHODS

This retrospective cohort study included all nulliparous women with singleton VAD in one academic institution. Study group parturients were maternal age ≥ 35 years and controls < 35. Power analysis revealed that 225 women/group would be sufficient to detect a difference in the rate of third- and fourth-degree perineal tears (primary maternal outcome) and umbilical cord pH < 7.15 (primary neonatal outcome). Secondary outcomes were maternal blood loss, Apgar scores, cup detachment, and subgaleal hematoma. Outcomes were compared between groups.

RESULTS

From 2014 to 2019, 13,967 nulliparas delivered at our institution. Overall, 8810 (63.1%) underwent normal vaginal delivery, 2432 (17.4%) instrumental, and 2725 (19.5%) cesarean. Among 11,242 vaginal deliveries, 10,116 (90%) involved women < 35, including 2067 (20.5%) successful VAD vs. 1126 (10%) women ≥ 35 years with 348 (30.9%) successful VAD (p < 0.001). Rates of third- and fourth-degree perineal lacerations were 6 (1.7%) with advanced maternal age and 57 (2.8%) among controls (p = 0.259). Cord pH < 7.15 was similar: 23 (6.6%) study group and 156 (7.5%) controls (p = 0.739).

CONCLUSION

Advanced maternal age and VAD are not associated with higher risk for adverse outcomes. Older, nulliparous women are more likely to undergo vacuum delivery than younger parturients.

The prevention of perineal trauma during vaginal birth

Perineal trauma after vaginal birth is common, with approximately 9 of 10 women being affected. Second-degree perineal tears are twice as likely to occur in primiparous births, with a incidence of 40%. The incidence of obstetrical anal sphincter injury is approximately 3%, with a significantly higher rate in primiparous than in multiparous women (6% vs 2%). Obstetrical anal sphincter injury is a significant risk factor for the development of anal incontinence, with approximately 10% of women developing symptoms within a year following vaginal birth. Obstetrical anal sphincter injuries have significant medicolegal implications and contribute greatly to healthcare costs. For example, in 2013 and 2014, the economic burden of obstetrical anal sphincter injuries in the United Kingdom ranged between £3.7 million (with assisted vaginal birth) and £9.8 million (with spontaneous vaginal birth). In the United States, complications associated with trauma to the perineum incurred costs of approximately $83 million between 2007 and 2011. It is therefore crucial to focus on improvements in clinical care to reduce this risk and minimize the development of perineal trauma, particularly obstetrical anal sphincter injuries. Identification of risk factors allows modification of obstetrical practice with the aim of reducing the rate of perineal trauma and its attendant associated morbidity. Risk factors associated with second-degree perineal trauma include increased fetal birthweight, operative vaginal birth, prolonged second stage of labor, maternal birth position, and advanced maternal age. With obstetrical anal sphincter injury, risk factors include induction of labor, augmentation of labor, epidural, increased fetal birthweight, fetal malposition (occiput posterior), midline episiotomy, operative vaginal birth, Asian ethnicity, and primiparity. Obstetrical practice can be modified both antenatally and intrapartum. The evidence suggests that in the antenatal period, perineal massage can be commenced in the third trimester of pregnancy to increase muscle elasticity and allow stretching of the perineum during birth, thereby reducing the risk of tearing or need for episiotomy. With regard to the intrapartum period, there is a growing body of evidence from the United Kingdom, Norway, and Denmark suggesting that the implementation of quality improvement initiatives including the training of clinicians in manual perineal protection and mediolateral episiotomy can reduce the incidence of obstetrical anal sphincter injury. With episiotomy, the International Federation of Gynecology and Obstetrics recommends restrictive rather than routine use of episiotomy. This is particularly the case with unassisted vaginal births. However, there is a role for episiotomy, specifically mediolateral or lateral, with assisted vaginal births. This is specifically the case with nulliparous vacuum and forceps births, given that the use of mediolateral or lateral episiotomy has been shown to significantly reduce the incidence of obstetrical anal sphincter injury in these groups by 43% and 68%, respectively. However, the complications associated with episiotomy including perineal pain, dyspareunia, and sexual dysfunction should be acknowledged. Despite considerable research, interventions for reducing the risk of perineal trauma remain a subject of controversy. In this review article, we present the available data on the prevention of perineal trauma by describing the risk factors associated with perineal trauma and interventions that can be implemented to prevent perineal trauma, in particular obstetrical anal sphincter injury.

Family medicine physician identification of obstetric lacerations: a US national survey

INTRODUCTION AND HYPOTHESIS

We evaluated family medicine obstetric providers' identification and categorization of vaginal delivery lacerations in the USA. We hypothesized that there would be inaccuracy in family medicine physicians' identification of vaginal delivery injuries, similar to our previous studies of midwives and obstetricians (OBs).

METHODS

We included clinically active physicians who attended deliveries within 2 years and evaluated their identification and categorization of delivery lacerations using descriptive text and visual images. We asked about their education on this topic and how they document lacerations in the labor and delivery record.

RESULTS

We analyzed 250 completed responses (70% of opened surveys). Fifty-five percent of respondents characterized their obstetric laceration training as "good" or "excellent" and half previously had education on obstetric lacerations. The median accuracy overall for the classification and identification of perineal lacerations was 78% (IQR 56-91%). Respondents frequently mischaracterized nonperineal lacerations. Few respondents (36%) reported using the third-degree injury subclassification system. In adjusted analysis, the highest scoring respondents were board certified in family medicine, with fewer years in practice, and a higher obstetric volume.

CONCLUSIONS

Obstetric laceration diagnoses may be inaccurate, which could influence perinatal quality and patient outcomes. We found gaps in knowledge similar to previous reports on midwives and obstetricians in the USA. These data suggest a need for increased education and training on obstetric injuries, perhaps especially for physicians with less obstetric activity. Improved categorization and identification of vaginal delivery trauma can impact management and improve women's postpartum care and long-term pelvic floor outcomes.

A systematic review and a meta-analysis on the incidence of obstetric anal sphincter injuries during vaginal delivery

AIM

The incidence of obstetric anal sphincter injuries (OASIS) has increased in the past two decades despite improved awareness of the risk factors. This study aimed to define the incidence of OASIS in women with different features (instrumental delivery or other variables).

METHODS

A systematic review was conducted on articles reporting the incidence of OASIS. This review aims to examine the association of instrumentation and OASIS by performing a formal systematic review of the published literature. Databases used for the research were MEDLINE, Embase, CINAHL and 'Maternity and infant care' databases.

RESULTS

Two independent reviewers screened the selected articles. 2326 duplicates were removed from the total of 4907 articles. The remaining 2581 articles were screened for title and abstract. 1913 articles were excluded due to irrelevance. The remaining 300 were screened as full text. Primiparity associated with the use of forceps were the features associated with the highest incidence of OASIS in the selected articles (19.4%). OASIS in all women had an overall incidence of 3.8%. The incidence of OASIS in all women by geographical region was the highest (6.5%) in North America.

CONCLUSIONS

There are various factors that impact on the incidence of OASIS and the combination of some of these, such as the use of forceps in primiparas, resulted in the highest incidence of OASIS. The lack of international consensus is limiting the improvements that can be done to reduce OASIS rates and improve best clinical practice.

Pregnancy, parturition and postpartum considerations among patients with vulvar lichen sclerosus: A retrospective cross-sectional online survey

OBJECTIVE

Characterise VLS and obstetric considerations among women during pregnancy, parturition and postpartum.

DESIGN

Retrospective cross-sectional online survey, 2022.

SETTING

International, English-speakers.

POPULATION

Self-identified individuals aged 18-50 diagnosed with VLS with symptom onset prior to pregnancy.

METHODS

Participants recruited from social media support groups and accounts, completed a 47-question survey including yes/no, multiple answer, and free-text responses. Data were analysed with frequency, means and the Chi-square test.

MAIN OUTCOME MEASURES

VLS symptom severity, mode of delivery, perineal laceration, source and sufficiency of information provided about VLS and obstetrics, anxiety about delivery, and postpartum depression.

RESULTS

Of 204 responses, 134 met inclusion criteria, encompassing 206 pregnancies. Mean respondent age was 35 years (SD 6) and mean age of VLS symptom onset, diagnosis and birth, was 22 (SD 8), 29 (SD 7) and 31 (SD 4) years, respectively. Symptoms decreased in 44% (n = 91) of pregnancies and increased during the postpartum period in 60% (n = 123). In all, 67% (n = 137) of pregnancies resulted in vaginal birth and 33% (n = 69) in caesarean birth. Anxiety for delivery due to VLS symptoms was reported by 50% (n = 103); 31% (n = 63) experienced postpartum depression. Of respondents previously diagnosed with VLS, 60% (n = 69) used topical steroids prior to pregnancy, 40% (n = 45) were treated during pregnancy and 65% (n = 75) postpartum. In all, 94% (n = 116) reported receiving an insufficient amount of information on the topic.

CONCLUSION

In this online survey, we found reported symptom severity remained unchanged or decreased during pregnancy, but increased postpartum. Use of topical corticosteroids decreased during pregnancy compared with before and after pregnancy. Half of the respondents reported anxiety regarding VLS and delivery.

Differences in rates of severe perineal trauma between midwife-led and obstetrician-led care in the Netherlands: A nationwide cohort study

Objective

To investigate trends and rates of severe perineal trauma (SPT), also known as obstetric anal sphincter injury (OASI), between midwife-led and obstetrician-led care in the Netherlands, and factors associated with SPT.

Methods

This nationwide cohort study included registry data from 2000 to 2019 (n = 2,169,950) of spontaneous vaginal births of term, live, cephalic, single infants, without a (previous) caesarean section or assisted vaginal birth.First, trends of SPT and episiotomy were shown. Second, differences in SPT rates between midwife- and obstetrician-led care were assessed. Third, associations of care factors with SPT were examined. Multivariable logistic regression analyses were used to determine which factors were important in the associations. All outcomes were stratified for parity.

Results

Over time, the SPT incidence increased mainly in midwife-led care and episiotomy rates decreased. Compared to midwife-led care, SPT rates were lower in obstetrician-led care among primiparous women (aOR 0.78; 99 % CI 0.74-0.81) and comparable among multiparous women (aOR 1.04; 99 % CI 0.99-1.10). Among women without epidural analgesia, these differences were smaller for primiparous women (aOR 0.88; 99 % CI 0.84-0.92), but the SPT rate was higher in obstetrician-led care among multiparous women (aOR 1.09; 99 % CI 1.03-1.15). Among women without shoulder dystocia, induction, augmentation, and pain medication, SPT rates were comparable among primiparous women, but higher among multiparous women in obstetrician-led care. In midwife-led care, SPT occurred more often among hospital versus home births. In obstetrician-led care, lower SPT incidences were found among births with epidural analgesia and for multiparous women with induction or augmentation.

Conclusions

Iinduction, augmentation, and epidural analgesia in obstetrician-led care may be an explanatory factor for the higher incidence of SPT among primiparous women in midwife-led care. More research is needed to explain differences in SPT rates and to understand how SPT can be prevented, while maintaining a high intact perineum rate.

Does transperineal ultrasound predict the risk of perineal trauma in women with term pregnancy? A prospective observational study

PURPOSE

This study was conducted to evaluate the prevalence of perineal trauma during childbirth and to assess the correlations of the pelvic floor dimensions and fetal head station with obstetric trauma in a prospectively recruited cohort of women.

METHODS

The study included women with a gestational age of at least 37 weeks, who were carrying a single fetus in a cephalic presentation. Transperineal ultrasound (TPU) was performed prior to the onset of labor or labor induction. The purpose was to measure the anteroposterior diameter (APD) of the levator ani muscle (LAM) and the angle of progression, at both rest and maximum Valsalva maneuver. The head-perineum distance was assessed only at rest.

RESULTS

A total of 296 women were included. Of the 253 women who delivered vaginally, 19% (48/253) experienced no perineal trauma, 18.2% (46/253) received an episiotomy during childbirth, 34.4% (87/253) sustained a first-degree laceration, 25.3% (64/253) had a second-degree laceration, and 3.2% had a third- or fourth-degree laceration (8/253). Women with episiotomy had a significantly shorter median APD under Valsalva than women without perineal trauma. Furthermore, women with LAM coactivation (identified by a negative difference between the APD at Valsalva and the APD at rest) were approximately three times more likely to undergo an operative vaginal delivery and over five times more likely to sustain a third- or fourth-degree tear during childbirth than women who exhibited normal relaxation of the LAM during the Valsalva maneuver.

CONCLUSION

TPU may predict the risk of perineal trauma in women with term pregnancy during childbirth.

The infection, cervical and perineal lacerations in relation to postpartum hemorrhage following vaginal delivery induced by Cook balloon catheter

OBJECTIVE

To identify whether infection, cervical laceration and perineal laceration are associated with postpartum hemorrhage in the setting of vaginal delivery induced by Cook balloon catheter.

MATERIALS AND METHODS

The retrospective study included 362 women who gave birth vaginally at or beyond 37 weeks of gestation with a diagnosis of postpartum hemorrhage between February 2021 to May 2022, of which including 216 women with induction of labor (Cook balloon catheter followed by oxytocin or oxytocin) and 146 women with spontaneous delivery. Risk factors for postpartum hemorrhage were collected and compared.

RESULTS

362 women were divided into three groups, group 1 with spontaneous delivery, group 2 with oxytocin, group 3 with Cook balloon catheter followed by oxytocin. There was no significant difference in incidence of infection within three groups (P > 0.05). The rate of cervical laceration and perineal laceration was significantly higher in group 3 compared with groups 2 and 1 (P < 0.05); Multivariate logistic regression analysis found that compared with group 1, either group 3 or group 2 was associated with increased risks of cervical laceration and perineal laceration (P < 0.05), and compared with group 2, group 3 was not associated with increased risks of cervical laceration and perineal laceration (P > 0.05).

CONCLUSION

Infection, cervical laceration and perineal laceration are identified not to be independent risk factors for postpartum hemorrhage for women undergoing labor with Cook balloon catheter; Cervical laceration and perineal laceration increase the risk of postpartum hemorrhage in women with labor induction.

Childbirth-related episiotomy and tear in relation to risk of postpartum depression: a retrospective cohort study on Omani mothers

AIMS/BACKGROUND

Studies on the association between perineal trauma (episiotomy and tear) and the risk of postpartum depression in Omani mothers are scarce. This study aimed to screen women for the risk of postpartum depression and associated maternal adverse outcomes (episiotomy and tear) in newly delivered Omani mothers.

DESIGN/METHODS

Mothers were screened for postpartum depression using only the Edinburgh Postnatal Depression Scale (EPDS), with cut-offs of 1-12 indicating low risk and 13-30 indicating high risk. Data on birth outcomes were collected retrospectively from the medical records. Descriptive analyses, group comparisons, and linear regression analyses were conducted.

RESULTS

Of the 262 participating mothers (total sample, i.e. mothers with and without depression), 19.0% had an episiotomy, 29.0% had tears, and 52.0% had an intact perineum after their childbirth. The total EPDS score was significantly higher among mothers with episiotomy (10.4, SD = 5.4) compared to those with tears (8.1, SD = 4.8) and those with intact perineum (9.4, SD = 4.9) (p-value <0.05). Lower levels of depression (-2.23 points on average) were significantly (p-value <0.05) associated with higher levels of perineum status (coded as 1 = episiotomy, 2 = other). Mothers who had a tear or episiotomy had on average 1.24 points higher EPDS scores compared to mothers with an intact perineum, although not significant (p-value >0.05).

CONCLUSIONS

Policymakers and clinicians are recommended to consider following up mothers with adverse birth outcomes to outline the risk of developing postpartum depression, at the same time as they routinely screen all mothers for risk of postpartum depression during their postpartum visits.

Flat Magnetic Stimulation for Urge Urinary Incontinence

Background and Objectives: Strategies for overactive bladder syndrome (OAB) management involve, among others, strengthening the bladder outlet to suppress urgency and neuromodulating the sacral roots. Magnetic stimulation (MS) is a technology that involves an extracorporeal device that is able to provide an electromagnetic field specifically designed to interact with pelvic floor neuromuscular tissue. The resulting tissue electrical activity induces contraction of the pelvic muscle and neuromodulation of the S2-S4 sacral roots. Flat Magnetic Stimulation (FMS) is a relevant advancement involving homogeneous electromagnetic fields, which are able to optimize the effect on the entire pelvic area. However, the benefits of this new technology for OAB syndrome are poorly known. Consequently, the aim of our study is to analyze the outcomes and quality of life (QoL) impact of FMS with Dr. Arnold (DEKA, Calenzano, Italy) in women suffering from OAB syndrome associated with urinary incontinence. Materials and Methods: This prospective study included patients with OAB, urge urinary incontinence, and no ongoing OAB treatments. At baseline (T0), the Incontinence Impact Questionnaire (IIQ-7), the Female Sexual Function Index (FSFI-19), and the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form (ICIQ-UI SF) were collected. Patients underwent 8 FMS sessions of 25 min each in one month. At the termination of the therapy (T1), women repeated the ICIQ-UI SF, FSFI-19, and IIQ-7 tools. Moreover, the Patient Global Impression of Improvement (PGI-I) questionnaire was collected to evaluate the cure rate. Results: Our study enrolled a total of 57 consecutive patients. Most women had at least one second- or third-line treatment before FMS, while the remaining naive patients had contraindications to pharmacological treatments. No women reported adverse effects during the treatment. After the treatment, we observed a decrease in the IIQ-7 (p < 0.001) and ICIQ-UI SF scores (p < 0.001) and an improvement in sexual function (p < 0.001) evaluated with FSFI-19. According to PGI-I scores, 42 (73.7%) women referred to some kind of improvement, scoring ≤ 3 points. Specifically, 8.7% of patients considered themselves very much improved, 29.8% much improved, 35.1% minimally improved, and 26.3% found no changes. FMS was effective in treating OAB symptoms without any adverse effects. The mechanism is supposed to be related to suppressing the initiation of micturition. This makes FMS a promising device for treating naive and refractory urge urinary incontinence. Conclusions: The new FMS represents a promising non-pharmacological option for the treatment of naive and refractory OAB.

The association of maternal obesity and obstetric anal sphincter injuries at time of vaginal delivery

BACKGROUND

The risk of third- and fourth-degree perineal laceration after vaginal delivery in patients with obesity is relatively understudied and has mixed findings in existing literature.

OBJECTIVE

This study aimed to examine the association of maternal obesity and obstetric anal sphincter injuries at vaginal delivery.

STUDY DESIGN

The Healthcare Cost and Utilization Project's National Inpatient Sample was retrospectively queried to examine 7,385,341 vaginal deliveries from January 2017 to December 2019. The exposure assignment was obesity status. The main outcomes were third- and fourth-degree perineal lacerations after vaginal delivery. Statistical analysis examining the exposure-outcome association included (1) inverse probability of treatment weighting with log-Poisson regression generalized linear model to account for prepregnant and pregnant confounders for the exposure and (2) multinomial regression model to account for delivery factors in the inverse probability of treatment weighting cohort. The secondary outcomes included (1) the temporal trends of fourth-degree laceration and its associated factors at cohort level and (2) risk factor patterns for fourth-degree laceration by constructing a classification tree model.

RESULTS

In the inverse probability of treatment weighting cohort, patients with obesity were less likely to have fourth-degree lacerations and third-degree lacerations than patients without obesity (fourth-degree laceration: 2.3 vs 3.9 per 1000 vaginal deliveries, respectively; adjusted odds ratio, 0.62; 95% confidence interval, 0.56-0.69; third-degree laceration: 15.6 vs 20.1 per 1000 vaginal deliveries, respectively; adjusted odds ratio, 0.79; 95% confidence interval, 0.76-0.82). In contrast, in patients with obesity vs those without obesity, forceps delivery (54.7 vs 3.3 per 1000 vaginal deliveries, respectively; adjusted odds ratio, 17.73; 95% confidence interval, 16.17-19.44), vacuum-assisted delivery (19.8 vs 2.9 per 1000 vaginal deliveries, respectively; adjusted odds ratio, 5.18; 95% confidence interval, 4.85-5.53), episiotomy (19.2 vs 2.8 per 1000 vaginal deliveries, respectively; adjusted odds ratio, 3.95; 95% confidence interval, 3.71-4.20), and shoulder dystocia (17.8 vs 3.4 per 1000 vaginal deliveries, respectively; adjusted odds ratio, 2.60; 95% confidence interval, 2.29-2.94) were associated with more than a 2-fold increased risk of fourth-degree perineal laceration. Among the group with obesity, patients who had forceps delivery and shoulder dystocia had the highest incidence of fourth-degree laceration (105.3 per 1000 vaginal deliveries). Among the group without obesity, patients who had forceps delivery, shoulder dystocia, and macrosomia had the highest incidence of fourth-degree laceration (294.1 per 1000 vaginal deliveries). The incidence of fourth-degree perineal laceration decreased by 11.9% over time (P trend=.004); moreover, forceps delivery, vacuum-assisted delivery, and episiotomy decreased by 3.8%, 7.6%, and 29.5%, respectively (all, P trend<.05).

CONCLUSION

This national-level analysis suggests that patients with obesity are less likely to have obstetric anal sphincter injuries at the time of vaginal delivery. Furthermore, this analysis confirms other known risk factors for fourth-degree laceration, such as forceps delivery, vacuum-assisted delivery, episiotomy, and shoulder dystocia. However, we noted a decreasing trend in fourth-degree lacerations, which may be due to evolving obstetrical practices.

Risk factors associated with third- and fourth-degree perineal lacerations in singleton vaginal deliveries: a comprehensive United States population analysis 2016-2020

OBJECTIVES

Perineal lacerations are a common complication of vaginal birth, affecting approximately 85 % of patients. Third-and fourth-degree perineal lacerations (3/4PL) remain a significant cause of physical and emotional distress. We aimed to perform an extensive assessment of potential risk factors for 3/4PL based on a comprehensive and current US population database.

METHODS

Retrospective population-based cohort analysis based on the US Centers for Disease Control and Prevention Natality Live Birth online database between 2016-2020. Baseline characteristics were compared between women with 3/4PL and without 3/4PL by using Pearson's Chi-squared test with statistical significance set at p<0.05. Bonferroni correction was used to account for multiple comparisons. Multivariable logistic regression was performed to evaluate the association between a variety of potential risk factors and the risk of 3/4P.

RESULTS

Asians/Pacific Islanders had the highest risk of 3/4PL (2.6 %, aOR 1.74). Gestational hypertension and preeclampsia were associated with increased risk of 3/4PL (aOR 1.28 and 1.34, respectively), as were both pre-gestational and gestational diabetes (aOR 1.28 and 1.46, respectively). Chorioamnionitis was associated almost double the risk (aOR 1.86). Birth weight was a major risk factor (aOR 7.42 for greater than 4,000 g), as was nulliparity (aOR 9.89).

CONCLUSIONS

We identified several maternal, fetal, and pregnancy conditions that are associated with an increased risk for 3/4PL. As expected, nulliparity and increased birth weight were associated with the highest risk. Moreover, pregestational and gestational diabetes, hypertensive disorders of pregnancy, Asian/Pacific Islander race, and chorioamnionitis were identified as novel risk factors.

In vivo assessment of the elastic properties of the external anal sphincter in term pregnant women using shear wave elastography

INTRODUCTION AND HYPOTHESIS

The objective was to assess the intraobserver intersession and interobserver intrasession reliability of shear wave elastography applied to the external anal sphincter in term pregnant women.

METHODS

This prospective study involved nulliparous pregnant women at 37 weeks or more with two visits (V1: one observer; V2 two observers) planned within a 12-h to 7-day interval. Measurements were performed using an Aixplorer V12® device with an SL 18-5 linear probe using a transperineal approach, allowing a measurement of the shear modulus (SM) in kPa. Measures were performed at rest, Valsalva maneuver, and maximal contraction. Reliability was assessed using the intraclass correlation coefficient (ICC). The study was approved by an ethics committee (ID RCB: 2020-A00764-65).

RESULTS

A total of 37 women were included. Intraobserver reliability was excellent at rest (ICC = 0.91 [0.84-0.95) and good during the Valsalva maneuver (ICC = 0.83 [0.72-0.90]) and contraction (ICC = 0.85 [0.75-0.91]). Interobserver reliability was good at rest (ICC = 0.79 [0.66-0.87]) and during Valsalva (ICC = 0.84 [0.73-0.90]), but moderate during contraction (ICC = 0.70 [0.53-0.82]).

CONCLUSIONS

Shear wave elastography is a reliable tool for assessing the elastic properties of the external anal sphincter in term pregnant women.

Incidence of obstetric anal sphincter injuries following breech compared to cephalic vaginal births

INTRODUCTION

Obstetric anal sphincter injuries (OASIs) at the time of childbirth can lead to serious consequences including anal incontinence, dyspareunia, pain and rectovaginal fistula. These types of lesions and their incidence have been well studied after cephalic presentation deliveries, but no publications have specifically addressed this issue in the context of vaginal breech delivery. The goal of our study was to evaluate the incidence of OASIs following breech deliveries and compare it with cephalic presentation births.

METHODS

This was a retrospective cohort study involving 670 women. Of these, 224 and 446 had a vaginal birth of a fetus in the breech (breech group) and cephalic (cephalic group) presentations respectively. Both groups were matched for birthweight (± 200 g), date of delivery (± 2 years) and vaginal parity. Main outcome of interest was to evaluate the incidence of OASIs following breech vaginal birth compared to cephalic vaginal births. Secondary endpoints were the incidence of intact perineum or first-degree tear, second-degree perineal tear and rates of episiotomies in each group.

RESULTS

There was no statistically significant difference in OASIs incidence between the breech and cephalic groups (0.9% vs. 1.1%; RR 0.802 (0.157; 4.101); p = 0.31). There were more episiotomies in the breech group (12.5% vs. 5.4%, p = 0.0012) and the rate of intact or first-degree perineum was similar in both groups (74.1% vs. 75.3%, p = 0.7291). A sub-analysis excluding patients with episiotomy and history of OASIs did not show any statistically significant difference either.

CONCLUSION

We did not demonstrate a significant difference in the incidence of obstetric anal sphincter injuries between women who had a breech vaginal birth compared to cephalic.

Is there still an indication for episiotomy? Results from a French national database analysis

OBJECTIVE

To assess the link between mediolateral episiotomy and the occurrence of obstetrical anal sphincter injury (OASIS).

METHODS

Data were collected from the national database (PMSI; Programme de Médicalisation des Systèmes d'Information). Women between 18 and 50 years old, undergoing a vaginal delivery in France in 2018 were included. The main outcome was factors associated with a higher adjusted OASIS rate after a vaginal delivery.

RESULTS

Of 623 003 women with a vaginal delivery, 239 949 were primiparous (38.5%), 62 310 experienced mediolateral episiotomy (10.0%) and 7077 had a third- or fourth-degree perineal tear (1.14%). Risk factors for OASIS were primiparity (adjusted odds ratio [OR] 2.97), shoulder dystocia (aOR 2.57), instrumental delivery (aOR 2.81), gestational diabetes (aOR 1.20), and post-term delivery (aOR 1.53). Mediolateral episiotomy increased the occurrence of OASIS for women without an instrumental delivery, either for parous (OR 1.32, 95% confidence interval [CI] 1.07-1.62) or primiparous (OR 1.26, 95% CI 1.13-1.39) women. In contrast, episiotomy among primiparous women with episiotomy and a vacuum or forceps delivery significantly decreased the risk for OASIS (OR 0.62, 95% CI 0.56-0.67).

CONCLUSIONS

The practice of routine episiotomy should be discouraged. Selective mediolateral episiotomy should be considered with extreme caution and mainly for primiparous women during instrumental vaginal delivery. Further randomized trial may confirm such results.

Mode of delivery and birth outcomes in relation to the duration of the passive second stage of labour: A retrospective cohort study of nulliparous women

OBJECTIVE

To investigate the mode of delivery and birth outcomes in relation to the duration of the passive second stage of labour in nulliparous women.

METHODS AND FINDINGS

A retrospective cohort study of all nulliparous women (n = 1131) at two delivery units in Sweden. Maternal and obstetric data were obtained from electronic medical records during 2019. The passive second stage was defined as the complete dilation of the cervix until the start of the active second stage. The duration of the passive second stage was categorized into three groups: 0 to 119 min (0 to <2 h), 120-239 min (2- <4h) and ≥240 min (≥4h). Differences between the groups were examined using t-test and Chi2-tests and regression analyses were used to analyse adjusted odds ratio with 95% confidence intervals. The primary outcome was mode of delivery in relation to the duration of the passive second stage and the secondary outcomes covered a series of adverse maternal and neonatal birth outcomes. The rates of instrumental and caesarean deliveries increased as the duration of the passive second stage increased. A ≥4-hour duration of the passive second stage was associated with a nine-times increased risk of caesarean section, and a four-times risk of instrumental delivery compared to a duration of <2 hours in the adjusted analyses. No differences were found in the maternal birth outcomes. The risk of a 5-minute Apgar score <7 was increased in the 2-<4h group. A longer passive second stage was not associated with an increased risk of negative birth experience.

CONCLUSIONS

Our study demonstrates an increased risk of operative delivery for a longer duration (>2h) of the passive second stage in nulliparous women, although most of the women gave birth by spontaneous vaginal delivery even after ≥4 hours. There was no evidence of an increased risk of adverse maternal outcomes in a longer duration of the passive second stage but there were indications of increased adverse neonatal outcomes. Assessment of fetal well-being is important when the duration of the passive phase is prolonged.

Time trends in episiotomy and severe perineal tears in Portugal: a nationwide register-based study

INTRODUCTION

Rates of episiotomy and severe perineal tears (SPT) are indicators of the quality of obstetric care. Time-trends in the reported occurrence of episiotomy and SPT can contribute to understand both, changes in care and in the frequency of risk factors. Therefore, we aimed to estimate time trends in the frequency of SPT in Portugal and its relationship with episiotomy.

METHODS

We conducted a nationwide register-based study using data from the national inpatient database of all Portuguese public hospitals between 2000 and 2015. Time-trend analysis using joinpoint regression models was performed to identify trends (joinpoints) and compare time changes in the prevalence of SPT and risk factors expressed as annual percentage changes (APC) with 95% Confidence Intervals (95% CI). Poisson regression models were fitted to estimate whether time-trends in SPT rates were explained by changes in risk factors and to assess the association between episiotomy and SPT. Adjusted relative risk (aRR) and their respective 95% CI were obtained.

RESULTS

From 908,999 singleton vaginal deliveries, 20.6% were instrumental deliveries, 76.7% with episiotomy and 0.56% were complicated by SPT. Among women with non-instrumental deliveries and no episiotomy SPT decreased from 2009 onwards (1.3% to 0.7%), whereas SPT kept increasing in women with episiotomy for both non-instrumental (0.1% in 2000 to 0.4% in 2015) and instrumental deliveries (0.7% in 2005 to 2.3% in 2015). Time-trends in potential risk factors did not explain the observed increase in SPT. Episiotomy was associated with a decrease in SPT with adjusted RR varying between 2000 and 2015 from 0.18 (95%CI:0.13-0.25) to 0.59 (95%CI:0.44-0.79) for non-instrumental deliveries and from 0.45 (95%CI:0.25-0.81) to 0.50 (95%CI:0.40-0.72) for instrumental deliveries.

CONCLUSIONS

Our findings suggest that episiotomy rate could safely further decrease as the main factor driving SPT rates seems to be an increase in awareness and reporting of SPT particularly among women who underwent an episiotomy.

Maternal characteristics as indications for routine induction of labor: A nationwide retrospective cohort study

BACKGROUND

Maternal characteristics, such as parity and age, are increasingly considered indications for routine induction of labor of otherwise healthy women to prevent fetal and neonatal mortality. To fully balance the risks and benefits of induction of labor, we examined the association of additional relevant maternal characteristics and gestational age with fetal and neonatal mortality.

METHODS

We conducted a nationwide retrospective cohort study among a healthy Dutch population consisting of all singleton pregnancies in midwife-led care after 37 weeks of gestation in the period 2000-2018. We examined the association of maternal ethnicity, age, parity, and socioeconomic status with fetal and neonatal mortality, stratified by gestational age. The association of single characteristics was examined using descriptive statistics, and univariable and multivariable logistics regression analyses. The associations of multiple characteristics were examined using inter-categorical analyses and using interaction terms in the multivariable logistic regression analyses.

RESULTS

The results showed that ethnicity, age, parity, socioeconomic status, and gestational age did not act as single determinant of fetal and neonatal mortality. The probability of fetal and neonatal mortality differed among subgroups of women depending on which determinants were considered and the number of determinants included.

CONCLUSIONS

Decision-making about induction of labor to prevent fetal and neonatal mortality based on a single determinant may lead to overuse or underuse of IOL. A value-based health care strategy, addressing social inequity, and investing in better screening and diagnostic methods that employ an individualized and multi-determinant approach may be more effective at preventing fetal and neonatal mortality.

Obstetric Perineal Tears in Pregnant Adolescents and the Influencing Factors

STUDY OBJECTIVE

The incidence and risk factors of obstetric perineal tear occurrence in vaginal delivery of adolescent pregnant patients are not well established. We aimed to describe the incidence of obstetric perineal tears in adolescents and the maternal obstetric risk factors associated with this situation.

DESIGN

Retrospective cohort study SETTING: Department of Obstetrics and Gynecology, Tepecik Education and Research Hospital, Izmir, Turkey PARTICIPANTS: Adolescent pregnant patients (≤19 years) who delivered vaginally in our institution between January 2014 and January 2021 INTERVENTIONS AND MAIN OUTCOME MEASURES: The main outcome measures were the incidence of perineal tears, the degree of perineal tears, and the risk factors associated with severe perineal tears in adolescents. Severe perineal tears include third- and fourth-degree lacerations. A third-degree tear is defined as partial or complete disruption of the anal sphincter muscles, and a fourth-degree tear is defined as lacerations involving the rectal mucosa.

RESULTS

A total of 3441 adolescents who had a vaginal delivery were included in the study. The rate of severe perineal tear was 5.8% (200/3441). Risk factors associated with obstetric laceration in adolescents in multivariate analysis were nulliparity (OR = 1.72; 95% CI, 1.14-2.41; P = 0.007), high birth weight (OR = 4.1; 95% CI, 2.71-6.21; P < 0.001), and labor induction (OR = 1.36; 95% CI, 1.01-1.85; P = 0.02). Spontaneous onset of labor and previous delivery reduced the risk of severe perineal tear in adolescent pregnant patients (respectively, OR = 0.68; 95% CI, 0.51-0.94; P = 0.02 and OR = 0.51; 95% CI, 0.33-0.79; P = 0.007).

CONCLUSIONS

In adolescents, the risk of severe perineal tear was associated with nulliparity, birth weight, and labor induction. The only possible modifiable risk factor was labor induction.

The influence of the fundal pressure manoeuvre at delivery on the anal sphincter injury diagnosed with endoanal ultrasonography

OBJECTIVES

The fundal pressure manoeuvre (FPM) is a procedure where the fundus of the uterus is pushed through the abdominal wall by the midwifes and doctors to shorten the terminal phase of the second stage vaginal delivery. Nowadays its use is controversial and associated with many adverse effects. The aim of the study was to evaluate benefits and adverse maternal outcomes after FPM. The correlation of the FPM with episiotomy was evaluated. The role of the FPM on pelvic floor dysfunction such as anal incontinence due to anal sphincter injury was assessed.

STUDY DESIGN

The retrospective study was conducted between 2017 and 2021. The women who came to the postpartum examination to Gynaecology department for various reasons and gave vaginal birth to a singleton were included in the study. The women who had instrumental delivery were excluded. Minimal sample size was calculated with calculator.net and set on 45. Two groups were formed one with fundal pressure and one without, 96 and 90 patients respectively. The maternal, fetal, and obstetric factors that could be associated with the application of FPM were examined. The endoanal ultrasound examination was performed on all women included in the study.

RESULTS

The study did not show that FPM would lead to a more frequent occurrence of anal sphincter injury (p = 0.73), effect its location (p = 0.77) and depth (p = 0.97), however the test group tended to have longer ruptures compared to control group (p = 0.1). No statistically significant differences in episiotomies between control and test group (p = 0.075) were shown. Endoanal ultrasound showed discrepancy between clinically stated and ultrasonographical diagnoses of anal sphincter injuries. In 61,3% of patients with anal sphincter injury after FPM, reported one of the anal incontinence problems of varying degrees six months after delivery.

CONCLUSION

Given that the study proved that FPM is not correlated to the anal sphincter injury it can be used safely. The FPM should be performed carefully and only if necessary to safely finish the labour or in combination with instrumental delivery.

Is there an Association between Vaginal Birth after Cesarean Prediction and Obstetric Anal Sphincter Injury?

OBJECTIVE

This study aimed to estimate whether there is an association between the predicted probability of vaginal birth after cesarean delivery (VBAC) and the occurrence of obstetric anal sphincter injuries (OASIS).

STUDY DESIGN

This was a single-site retrospective cohort study of all women with a singleton vaginal birth after a previous cesarean section between January 2011 and December 2016. Women were divided into four ordinal groupings by the predicted probability of achieving vaginal birth after cesarean using the Maternal-Fetal Medicine Units Network VBAC calculator (less than 41%, 40.1-60%, 60.1-80%, and greater than 80%). The primary outcome was OASIS, defined as a 3rd or 4th degree perineal laceration. Bivariable and multivariable analyses were used to examine the association between predicted VBAC probability and OASIS.

RESULTS

In total, 1,411 women met inclusion criteria and 73 (5.2%) sustained OASIS. The median predicted probability of VBAC was lower in women with OASIS compared with those without OASIS (60% [interquartile range {IQR}: 48-70%] vs. 66% (IQR: 52-80%), p = 0.02]. On bivariable and multivariable logistic regression, predicted probability of VBAC was associated with increased odds of OASIS (less than 41% probability: adjusted odds ratio [aOR]: 3.18, 95% confidence interval [CI]: 0.90-11.21; 41-60% probability: aOR: 3.76, 95% CI: 1.34-10.57; 61-80% probability aOR: 3.47, 95% CI: 1.25-9.69) relative to women with a predicted probability of VBAC of greater than 80%.

CONCLUSION

Having a lower predicted probability of VBAC is associated with an increased risk of OASIS at the time of a VBAC relative to those with greater than 80% predicted probability. Incorporation of this aspect of maternal morbidity may inform risk-stratification at the time of trial of labor after cesarean, as well as the choice of performing an operative vaginal delivery.

KEY POINTS

· Predicted probability of VBAC is associated with OASIS.. · Low predicted probability of VBAC is associated with increased odds of OASIS.. · Forceps delivery was associated with the highest odds of OASIS..

French guidelines for restrictive episiotomy during instrumental delivery were not followed by an increase in obstetric anal sphincter injury

The objective was to assess the influence of the French guidelines in favor of a restrictive use of episiotomy on both episiotomy and obstetric anal sphincter injury (OASI) rates during instrumental delivery. It was aulticenter study involving 193 maternities between 2000 and 2016. We included women with a singleton pregnancy, with cephalic presentation at 34 weeks of gestation or more who underwent an instrumental delivery. The study period was divided into three phases: 2000-2005 (reference) 2006-2011, and 2012-2016. We calculated the adjusted relative risk (aRR) of episiotomy and OASI and investigated for changes in episiotomy and OASI rates over time by using Prais-Winsten regression. We considered 96,035 deliveries. The episiotomy's risk was lower in 2006-2011 (69.4%) and 2012-2016 (59.1%) compared to 2000-2005 (81.2%), respectively: aRR 0.93 [0.92-0.95] and 0.89 [0.87-0.90]. The OASI's risk was higher in 2006-2011 (2.5%) and 2012-2016 (3.1%) compared to 2000-2005, respectively: aRR 1.30 [1.10-1.53]) and 1.57 [1.33-1.85]. However, Prais-Winsten regression showed no difference in the OASI rate during the study period. We observed a massive decrease in episiotomy use and a moderate increase in crude OASI's rate but multivariate analysis failed to report an association between these outcomes.

Investigating the Effects of Different Sizes of Silicone Rubber Vacuum Extractors during the Course of Delivery on the Fetal Head: A Finite Element Analysis Study

During certain clinical situations, some parturients require instruments for operative vaginal delivery, and various designs of vacuum extractors may affect the fetal head. To investigate the biomechanical effects of divergent sizes of silicone rubber vacuum extractors, we employed finite element analysis in this study. First, we constructed computer models for different vacuum extractor sizes (diameters: 40 mm, 50 mm, 60 mm, and 70 mm), flat surface, hemispherical ball, and fetal head shape. A hemispherical ball was the main design for the vacuum extractor model, and the material used for the vacuum extractor was silicone rubber. Next, the settings of 1 mm vacuum extractor displacement and vacuum cap pressure of 60 cmHg were applied. The main observation markers of this study were the respective von Mises stresses on the vacuum extractor and skull by the reaction force on the fixed end. The concluded results revealed that vacuum extractors with larger diameters lead to greater reaction force, stress, and strain on fetal heads. Therefore, this study's biomechanical analytic consequences suggest that clinicians avoid selecting larger vacuum extractors during operative instrumental delivery so that fetal heads will experience less external force, deformation, and resultant complications. It could also provide a practical reference for obstetricians for instrumental vaginal delivery with the vacuum extractor made of silicone rubber.

A Search for Novel Risk Factors for Obstetric Anal Sphincter Injury

OBJECTIVE

The objective of this study is to evaluate factors associated with obstetric anal sphincter injury and identify modifiable risks.

METHODS

A retrospective case-control study was performed in women who gave birth at our institution between May 2008 and December 2012. Patients who had a third- or fourth-degree lacerations were compared with those who did not. Parity, stretch marks, age, body mass index, tobacco use, fetal weight, operative delivery, labor, and second stage duration were compared between groups. Multivariate direct logistic regression was conducted on all patients who had complete data to calculate the adjusted odds ratio.

RESULTS

We identified 299 patients with third- or fourth-degree lacerations and 8,459 patients without third- or fourth-degree lacerations during the time frame. Duration of second stage between 1 hour and 2 hours (P < 0.0001), duration of second stage greater than 2 hours (P < 0.0001), midline or unknown type episiotomy (P < 0.0001), mediolateral episiotomy (P < 0.0001), vacuum delivery (P < 0.0001), forceps delivery (P < 0.0001), fetal weight greater than 4,000 g (P < 0.0001), and antepartum stress urinary incontinence (P < 0.006) were associated with a significant increase in high-risk lacerations. This study did not find a statistically significant association between parity and these lacerations.

CONCLUSIONS

We, as others, found that episiotomy and operative delivery were modifiable risks of obstetrical care. Furthermore, even a short second stage of labor (1-2 hours) was associated with significant risk of injury.

Mediolateral episiotomy and risk of obstetric anal sphincter injuries and adverse neonatal outcomes during operative vaginal delivery in nulliparous women: a propensity-score analysis

Background

The potential protective effect of mediolateral episiotomy for obstetrical anal sphincter injuries (OASIs) remains controversial during operative vaginal delivery because of the difficulties to take into account the risk factors and clinical conditions at delivery; in addition, little is known about the potential benefits of mediolateral episiotomy on neonatal outcomes.

The objectives were to investigate the associations between mediolateral episiotomy and both OASIs and neonatal outcomes, using propensity scores.

Methods

We performed a retrospective population-based observational study from a perinatal registry that includes all births in a French region between 2010 and 2017. All nulliparous women with singleton pregnancy delivering by operative vaginal deliveries at 37 weeks gestational age or later were included. Inverse-probability-of-treatment weighting with propensity scores was used to minimize indication bias. OASIs was defined as third and fourth-degree tears according to Royal College of Obstetricians and Gynecologists. Two neonatal outcomes were studied: condition at birth (5-min Apgar score less than 7 and/or umbilical artery pH less than 7.10), and admission to neonatal intensive care unit.

Results

The study population consisted of 7589 women; 2880 (38.0%) received mediolateral episiotomy. After applying propensity scores, episiotomy was associated with a lower rate of OASIs in forceps/spatula delivery (2.3 vs 6.8%, Risk Ratio (RR) 0.38, 95% Confidence Interval (CI) 0.28–0.52) and in vacuum delivery (1.3 vs 3.4%, RR 0.27, 95% CI 0.20–0.38) as compared with no episiotomy. Mediolateral episiotomy was associated with better condition at birth in case of forceps/spatula delivery (4.5 vs 8.8%, RR 0.56, 95% CI 0.39–0.81). In cases of fetal distress (40.7%), mediolateral episiotomy was associated with better condition of infant at birth in women who delivered by forceps/spatula (4.2 vs 13.5%, RR 0.52, 95% CI 0.31–0.89). No association was found with neonatal unit admission (RR 0.93, 95% CI 0.50–1.74).

Conclusions

Use of mediolateral episiotomy was associated with a lower rate of OASIs during operative vaginal delivery, and in infants it was associated with better condition at birth following forceps/spatula delivery.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04396-6.

Can sonographic fetal head circumference measurement help predict Obstetric Anal Sphincter Injury?

OBJECTIVE

Obstetric Anal Sphincter Injuries (OASIS) occur in 2 to 19% of vaginal deliveries in the United States. Neonatal parameters such as birthweight above 4000g or neonatal head circumference above 37 cm are known risk factors for OASIS. We hypothesized that sonographic fetal Head Circumference (sfHC) size assessed by ultrasound antenatally could help predict OASIS.

METHODS

This study is a retrospective cohort study between 2005 and 2016. Antenatal ultrasound Head Circumference (sfHC) assessment, maternal demographics, and labor and delivery data were abstracted and compared in women with and without OASIS.

RESULTS

Of 2057 pregnant women that had sfHC assessment, 121 (5.8%) had OASIS. In the unadjusted analysis, sfHC above the 90^th percentile was associated with OASIS OR 1.12 (1.02-1.23) p=0.015. When adjusted for gestational age at delivery, maternal age, race, prolonged 2^nd stage, BMI, infant gender, and intrapartum oxytocin use, sfHC above the 90^th percentile remained significantly associated with OASIS (OR=1.13, 95% CI 1.00-1.27, p=0.050).

CONCLUSION

In our cohort, sfHC above the 90^th percentile was associated with a greater risk of OASIS. As OASIS significantly impacts short and long-term health outcomes such as perineal pain, dyspareunia, urinary and fecal incontinence, sfHC could be an additional antenatal marker to help clinicians counsel pregnant women about the risk of OASIS.

A nationwide cross-sectional survey of episiotomy practice in China

Background

A restrictive use of episiotomy was recommended by the obstetric society in China, but limited information on the epidemiology and the effects of restrictive use of episiotomy on maternal and fetal outcomes have been published.

Methods

The China Labor and Delivery Survey is a cross-sectional investigation with a cluster random sampling scheme in 2015-2016 with the aim to describe detailed epidemiology of labor and delivery in China. We calculated the episiotomy rate by parity using the survey data. Associated factors of episiotomy were selected using mixed models with a random effect for the hospital-level clustering. Logistic regression models were fitted to examine the effects of mediolateral episiotomy on maternal and neonatal outcomes among the propensity score-matched women.

Findings

The episiotomy rate among vaginal births was 41·7% [95% confidence interval (CI): 40·1% - 43·2%] in nulliparae and 21·5% (95% CI: 19·4% - 23·5%) in multiparae in China. Associated factors of episiotomy included prepregnancy BMI, maternal diseases, and obstetric factors. More than half of episiotomies in nulliparae and one-fourth in multiparae had no indications. Mediolateral episiotomy without indicators increased the risk of 3^rd or 4^th degree perineal laceration [odds ratio (OR) =2·64, 95% CI: 1·08-6·48)] in nulliparae without neonatal benefits.

Interpretation

Episiotomy was performed more than medically necessary in China. Mediolateral episiotomy without indications more than doubled the risk of 3^rd and 4^th degree perineal laceration in nulliparae without neonatal benefits.

Funding

National Natural Science Foundation of China and Shanghai Health Commission Programme.

Classification and evaluation of episiotomy practices from 2004 to 2020 and association with OASIS

OBJECTIVE

To apply a new classification based on 7 clinically relevant subgroups to accurately describe episiotomy practices and evaluate the association between episiotomy and obstetrical anal sphincter injuries (OASIS) rates according to the classification's subgroups.

METHODS

Observational retrospective cohort study based on a population comprising 39487 women from 01/01/2004 to 31/12/2020 in a level III university maternity unit. The primary outcome was the overall episiotomy rate in the institution, its trend over the time as well as in each subgroup of obstetric population classification. Secondary outcome was the rate of OASIS third and fourth degree, its association with episiotomy practice.

RESULTS

The episiotomy rate decreased significantly from 43,2% to 20% in the total population. The overall OASIS rate was 0,34%, it remained significantly the same during the study period, although the association between OASIS and episiotomy was significant only in group 2 (Nulliparous with instrumental delivery) with a decrease of OASIS rate if using episiotomy (OR 0.5; 95% CI[0,3-0,8]).

CONCLUSION

The episiotomy rate can be decreased without exposing women to an increased risk of OASIS. It encourages restrictive practice of episiotomy, but episiotomy should be considered in case of nulliparous women with instrumental delivery.

Risk of obstetric anal sphincter injury among women who birth vaginally after a prior caesarean section: A state-wide cohort study

OBJECTIVE

Vaginal birth after caesarean (VBAC) has been suggested to be associated with an increased risk of obstetric anal sphincter injury (compared with primiparous women who birth vaginally). However, prior studies have been small, or used outdated methodology. We set out to validate whether the risk of obstetric anal sphincter injury among women having their first VBAC is greater than that among primiparous women having a vaginal birth.

DESIGN

State-wide retrospective cohort study.

SETTING

Victoria, Australia.

POPULATION

All births (455,000) between 2009-2014.

METHODS

The risk of severe perineal injury between first vaginal birth and first vaginal birth after previous caesarean section was compared, after adjustment for potential confounding variables. Covariates were examined using logistic regression for categorical data and Wilcoxon rank-sum test for continuous data. Missing data were handled using multiple imputation; the analysis was performed using regression adjustment and Stata v16 multiple imputation and teffects suites.

RESULTS

Women having a VBAC (n=5,429) were significantly more likely than primiparous women (n=123,353) to sustain a 3^rd or 4^th degree tear during vaginal birth (7.1 vs 5.7%, p<0.001). After adjustment for mode of birth, body mass index, maternal age, infant birthweight, episiotomy and epidural, there was a 21% increased risk of severe perineal injury (relative risk 1.21 (95%CI 1.07 - 1.38)).

CONCLUSIONS

Women having their first vaginal birth after caesarean section have a significant increased risk of sustaining a 3^rd or 4^th degree tear, compared with primiparous women having a vaginal birth. Patient counselling and professional guidelines should reflect this increased risk.

Pregnancy in adolescence in Brazil: associated factors with maternal age

Abstract Objectives: describing maternal characteristics, risk behavior, obstetric data, prenatal care and childbirth in adolescent mothers in Brazil (age groups: 12-16 years and 17-19 years). Methods: hospital-based cross-sectional study substantiated by Nascer no Brasil”, (Born in Brazil) data. The study encompassed puerperal adolescent mothers from all regions in the country, and their newborns. Chi-square test was used to compare adolescents in the 12-16 years old age group and those in the 17-19 years old age group. Results: pregnant women in the 12-16 years old age group mostly lived in the Northeast of Brazil (p=0.014); most of them did not have a partner (p<0.001), unplanned pregnancy (p<0.001), they had inadequate schooling for their age (p=0.033), had less than six prenatal consultations (p=0.021), were subjected to episiotomy (p=0.042) and accounted for the largest number of premature babies (p=0.014). Conclusions: puerperal women in the 12-16 years old age group presented vulnerability in their socioeconomic conditions, inadequate assistance at the prenatal and childbirth care, as well as their babies showed neonatal complications that pointed towards these adolescent mothers’ need of multidisciplinary care.

Temporal trends in obstetric anal sphincter injury from the first vaginal delivery in Austria, Canada, Norway, and Sweden

INTRODUCTION

Obstetric anal sphincter injuries (OASI) are severe complications that can cause considerable short- and long-term morbidity. Austria, Canada, Norway, and Sweden have similar socio-economic characteristics, and all four countries have access to national birth registers. In this study, we hypothesized that the incidence of OASI should be very similar for different obstetric scenarios in these four countries. Therefore, the aim was to compare the incidence of OASI in these four countries in primiparous women, with spontaneous or instrumental delivery (vacuum or forceps), and in women with a first vaginal birth after cesarean section (VBAC).

MATERIAL AND METHODS

Aggregated data on 1 933 930 vaginally delivered primiparous women and women with VBAC were retrieved from the birth registers gathered in Austria, Canada, Norway, and Sweden. The annual rate of OASI (ICD-10 codes O70.2-O70.3) was presented as the percentage of women with a spontaneous delivery, vacuum or forceps delivery, and a VBAC during the period 2004-2016.

RESULTS

The incidence of OASI varied considerably between countries and over time. Canada and Sweden had the highest rates, and Austria and Norway the lowest. In Norway, the rate of OASI decreased consistently for all types of deliveries after introducing a perineal protection program in 2004 (p < 0.001). During vacuum delivery, the incidence of OASI varied between countries from 4.1% to 15.5% across the study period. In Canada and Norway, the rate of OASI after a forceps delivery was similar in 2004 at ~20% and with differing trajectories to 24.3% (β 0.49) and 6.2% (β -1.15) (trend, all p < 0.001) in 2016.

CONCLUSIONS

This comparative register study suggests that there may be considerable potential for lowering the incidence of OASI. The perineal protection program implemented by Norway has been successful. Each country should critically, without prejudice, analyze their current clinical practices and rate of OASI and consider the best preventive strategy.

Predicting obstetrical anal sphincter injuries in patients who undergo vaginal birth after cesarean delivery

BACKGROUND

Women with a history of previous cesarean delivery must weigh the numerous potential risks and benefits of elective repeat cesarean delivery or trial of labor after cesarean delivery. Notably, 1 important risk of vaginal delivery is obstetrical anal sphincter injuries. Furthermore, the rate of obstetrical anal sphincter injuries is high among women undergoing vaginal birth after cesarean delivery. However, the risk of obstetrical anal sphincter injuries is not routinely included in the trial of labor after cesarean delivery counseling, and there is no tool available to risk stratify obstetrical anal sphincter injuries among women undergoing vaginal birth after cesarean delivery.

OBJECTIVE

This study aimed to develop and validate a predictive model to estimate the risk of obstetrical anal sphincter injuries in the setting of vaginal birth after cesarean delivery population to improve antenatal counseling of patients regarding risks of trial of labor after cesarean delivery.

STUDY DESIGN

This study was a secondary subgroup analysis of the Maternal-Fetal Medicine Units Network Trial of Labor After Cesarean Delivery prospective cohort (1999-2002). We identified women within the Maternal-Fetal Medicine Units Network cohort with 1 previous cesarean delivery followed by a term vaginal birth after cesarean delivery. This Maternal-Fetal Medicine Units Network Vaginal Birth After Cesarean Delivery cohort was stratified into 2 groups based on the presence of obstetrical anal sphincter injuries, and baseline characteristics were compared with bivariate analysis. Significant covariates in bivariate testing were included in a backward stepwise logistic regression model to identify independent risk factors for obstetrical anal sphincter injuries and generate a predictive model for obstetrical anal sphincter injuries in the setting of vaginal birth after cesarean delivery. Internal validation was performed using bootstrapped bias-corrected estimates of model concordance indices, Brier scores, Hosmer-Lemeshow chi-squared values, and calibration plots. External validation was performed using data from a single-site retrospective cohort of women with a singleton vaginal birth after cesarean delivery from January 2011 to December 2016.

RESULTS

In this study, 10,697 women in the Maternal-Fetal Medicine Units Network Trial of Labor After Cesarean Delivery cohort met the inclusion criteria, and 669 women (6.3%) experienced obstetrical anal sphincter injuries. In the model, factors independently associated with obstetrical anal sphincter injuries included use of forceps (adjusted odds ratio, 5.08; 95% confidence interval, 4.10-6.31) and vacuum assistance (adjusted odds ratio, 2.64; 95% confidence interval, 2.02-3.44), along with increasing maternal age (adjusted odds ratio, 1.05; 95% confidence interval, 1.04-1.07 per year), body mass index (adjusted odds ratio, 0.99; 95% confidence interval, 0.97-1.00 per unit kg/m²), previous vaginal delivery (adjusted odds ratio, 0.19; 95% confidence interval, 0.15-0.23), and tobacco use during pregnancy (adjusted odds ratio, 0.59; 95% confidence interval, 0.43-0.82). Internal validation demonstrated appropriate discrimination (concordance index, 0.790; 95% confidence interval, 0.771-0.808) and calibration (Brier score, 0.047). External validation used data from 1266 women who delivered at a tertiary healthcare system, with appropriate model discrimination (concordance index, 0.791; 95% confidence interval, 0.735-0.846) and calibration (Brier score, 0.046). The model can be accessed at oasisriskscore.xyz.

CONCLUSION

Our model provided a robust, validated estimate of the probability of obstetrical anal sphincter injuries during vaginal birth after cesarean delivery using known antenatal risk factors and 1 modifiable intrapartum risk factor and can be used to counsel patients regarding risks of trial of labor after cesarean delivery compared with risks of elective repeat cesarean delivery.

How can we improve our practices in obstetric anal sphincter injury prevention, diagnosis, and management of symptomatic women?

Obstetric anal sphincter injury (OASI) is strongly associated with a major negative impact on women's health. Due to the consequences of an undiagnosed and therefore unrepaired OASI, it is essential to prevent or at least diagnose OASI at childbirth. We need to promote training of professionals to improve OASI screening at childbirth. High-risk situations such as operative delivery must be identified and preventive strategies such as the choice of a less traumatic instrument (vacuum) and mediolateral episiotomy should be considered. For a woman with OASI and/or symptoms, postnatal consultation with a specialist on pelvic floor disorders is essential to correctly orient her toward an adequate care pathway and to eventually identify occult or underestimated OASI. More data are required on therapeutic approaches for symptomatic women, primarily including physical therapy, sacral neuromodulation, delayed sphincter repair and palliative devices.

A core outcome set development for a French national prospective study about the effect of mediolateral episiotomy on obstetric anal sphincter injury during operative vaginal delivery (INSTRUMODA)

BACKGROUND

We aimed at developing a core outcome and variables of interest set to investigate the effects of mediolateral episiotomy on Obstetric Anal Sphincter Injury (OASI) during and after operative delivery in nulliparous women in a large-scale one-year observational French study including 15,000 women (INSTRUMODA).

METHODS

A list of outcomes and variables of interest was suggested to obstetricians participating in the INSTRUMODA study using online questionnaires divided into 7 categories: the woman's history and course of pregnancy, course of labor, modalities of operative delivery, episiotomy characteristics, immediate maternal morbidity, one-year maternal morbidity, immediate neonatal morbidity. We used a three-round DELPHI method to reach a consensus. In the first round, outcomes and variables considered as essential by 70% or more of obstetricians were included in the corpus whereas they were excluded when 70% rated them as "not important". In the second round, non-consensual outcomes and variables were reassessed and excluded or definitively included if considered as "not important" or essential by 50% or more of the obstetricians. During the first round, obstetricians were invited to suggest new outcomes and/or variables that were then assessed in the second and third round. We used the same method to develop a core outcome and variables of interest set in a population of women in the community recruited via an association of patients. At the end of the procedure the core outcome and variables of interest sets were merged to provide the final core outcome set for the INSTRUMODA study.

RESULTS

Fifty-three obstetricians and 16 women filled out questionnaires. After the 3 rounds of Delphi procedure in each population, 74 outcomes and variables were consensually reported by obstetricians and 92 by women in the community. By mixing these two consensual corpora we reported a final consensual list of 114 variables of interest and outcomes for both obstetricians and women.

CONCLUSION

We established a core outcome and variables of interest set among obstetricians and women in the community to investigate the association between mediolateral episiotomy and OASI during operative delivery.

TRIAL REGISTRATION

The INSTRUMODA study was registered on https://clinicaltrials.gov on June 25, 2020 ( NCT04446780 ).

Severe Perineal Trauma in a Brazilian Southeastern Tertiary Hospital: A Retrospective Cohort Study

OBJECTIVE

This study aimed to investigate the prevalence of severe perineal trauma (obstetric and anal sphincter injury [OASIS]) in a tertiary high-risk pregnancy facility and the associated factors.

METHODS

A retrospective electronic chart review on perineal lacerations was performed from the period of April 2017 to February 2019. Obstetric and anal sphincter injury was diagnosed by a rectal examination. Primary outcome was the prevalence of OASIS (third- and fourth-degree perineal tear). Independent variables were maternal, intrapartum, and neonatal characteristics. Univariate and multivariate analyses with logistic regression models were performed. A P value lower than 0.05 was considered significant.

RESULTS

The prevalence of OASIS (third/fourth-degree laceration) was 1.51% (43/2846) in our population. Our population was mostly white (66.3%) and mostly primiparous (52.1%). By comparison, the prevalence of first/second-degree laceration was 43% (1223/2846). Selective episiotomy occurred in 18.73% (517/2761) of patients, and it was not associated with OASIS (P = 0.211). Advanced maternal age (P = 0.196), higher number of vaginal examinations (P = 0.169), fetal presentation (P = 0.533), and duration of second stage (P = 0.757) were not associated with OASIS. Univariate analysis has found that forceps delivery (odds ratio [OR], 3.68 [1.74-7.79]; P = 0.001), neonatal macrossomy (OR, 3.42 [1.02-11.43]; P = 0.045), and larger head circumference (OR, 1.15 [1.02-1.32]; P = 0.026) were risk factors for OASIS, whereas higher gravidity reduced the risk (OR, 0.61 [0.42-0.91] for OASIS. However, after multivariate analysis, only head circumference (OR, 1.86 [1.10-3.14]; P = 0.020) remained as a risk factor.

CONCLUSIONS

Larger neonatal head circumference increased in 86% the risk for severe perineal trauma in this cohort of women.

Management and consequences of obstetrical anal sphincter injuries: Review

Obstetrical anal sphincter injuries (OASI), formerly referred to as "complete" or "incomplete" perineal tears, are a frequent complication of childbirth. They can lead to intestinal consequences (anal incontinence, ano-genital fistula) or sexual consequences (dyspareunia, genital pain). The complexity of management of OASI lies in the multi-factorial nature of these consequences but also in the frequently lengthy interval before their appearance, often long after childbirth. Indeed, while 2.4% of women in childbirth develop OASI, up to 61% of them will present with anal incontinence15 to 25 years after childbirth. Immediate or delayed repair of the sphincter and perineum within a few hours of injury is therefore the rule, but there is no consensus on longer-term management. The patient must be educated on preventive actions (avoidance of pushing or straining, regularization of stool transit, muscle strengthening, etc.). Early detection of anal incontinence leads to prompt management, which is more effective. This review aims to synthesize the information necessary to provide clear and up-to-date patient information on OASI (risk factors and prevalence), the management of OASI, and the management of eventual complications in the setting of dedicated specialty consultations. Dedicated "post-OASI" consultations by a specialist in ano-perineal pathologies could therefore become a first step in the development of care for women, particularly by removing the "shameful" nature of the symptoms.

Risks and Associations of Third- and Fourth-Degree Lacerations: An Urban Single Center Experience

OBJECTIVE

Obstetric anal sphincter injuries (OASIs) are severe tears involving the external and internal anal sphincters. We aimed to document the incidence of OASIs within a racially and ethnically diverse institution to elucidate which maternal, fetal, and parturition factors may be associated with OASIs in minority subgroups.

METHODS

This was a retrospective unmatched case-control study of reproductive aged women who delivered between January 1, 2014, and December 31, 2017, at our institution. Data for maternal, fetal, and parturition factors were gathered through chart review. We also investigated the expertise level of the surgeon performing repairs and complications that developed in the postpartum period. Logistic regression analysis was used to compare women with third- and fourth-degree lacerations against the control group of women with first-degree, second-degree, or no lacerations.

RESULTS

Of the 23,362 deliveries between January 1, 2014, and December 31, 2017, the incidence of OASIs was 1%. Of our patients, 38% self-identified as Hispanic, 32% as Black, 13% as White, and 3.5% as Asian. Risk for OASIs was significantly increased in nulliparity, Pitocin use, operative deliveries, episiotomy, and prolonged second stage of labor. Black race and obesity were protective for OASIs. There was no significant difference in complication rates based on type of repair nor the provider level of training.

CONCLUSIONS

The incidence of OASIs at our institution is similar to current published literature. Our study population is unique in its overrepresentation of minority groups, offering insight into potentially distinctive risk and protective factors associated with OASIs.

Comparison of maternal and neonatal outcomes after forceps or spatulas-assisted delivery

OBJECTIVE

The aim of this study was to compare the perinatal outcomes associated with spatulas or forceps assisted delivery.

STUDY DESIGN

This is a bicentric retrospective cohort study including all assisted deliveries in cephalic presentation after 37 weeks of gestation, performed on singleton pregnancy with forceps and with spatulas in two tertiary centers. The main outcome was the rate of episiotomy. Secondary outcomes included obstetric anal sphincter injuries (OASIS), maternal outcomes and neonatal parameters.

RESULTS

Out of 37 002 deliveries, the overall rate of assisted delivery was 11.4 %, and 1 041 (2.8 %) assisted deliveries with forceps and 2 462 (6.7 %) spatulas deliveries were included. The rate of episiotomy was 90.3 % after forceps-assisted delivery and 70.9 % for spatulas (p < 0.001). The rate of OASIS was 7.2 % and 5.6 % respectively (p = 0.06). A slight but significant decrease in neonatal trauma after spatulas was observed.

CONCLUSION

In this retrospective cohort study, the episiotomy rate was higher with forceps assisted deliveries than with spatulas. Both instruments have low neonatal morbidity and are similar regarding OASIS.

The role of mediolateral episiotomy during vacuum-assisted vaginal delivery with soft cup devices

PURPOSE

This study evaluated whether episiotomy during vacuum-assisted delivery leads to fewer third- and fourth-degree tears.

METHODS

This was a retrospective cohort study of all nulliparas who underwent a singleton, soft cup, vacuum-assisted vaginal delivery in one institution, from January 2014 to August 2019. Failed vacuum deliveries were excluded. Based on power analysis calculation, a sample size of 500 women in each group was sufficient to detect an advantage of episiotomy, if present. Primary outcome was third- or fourth-degree perineal tear. Secondary outcomes were other maternal complications, and low neonatal cord pH and Apgar scores. Outcomes were compared between women with and without episiotomy.

RESULTS

During the study period, 2370 nulliparas had a vacuum-assisted vaginal delivery using soft vacuum cup and met the study inclusion criteria. Episiotomy was performed in 1868 (79%) women, and 502 (21%) delivered without episiotomy. Background characteristics were similar in both groups. There were no significant differences in the rates of third and fourth grade perineal lacerations between the two groups. Episiotomy was associated with higher rate of postpartum hemorrhage (p < 0.01) CONCLUSIONS: Using selective episiotomy for patients delivering vaginally with the assistance of soft cap vacuum does not increase third- or fourth-degree perineal tears.

Temporal trends in the incidence of and associations between the risk factors for obstetrical anal sphincter injuries

BACKGROUND

Obstetrical anal sphincter injuries are an important complication of vaginal deliveries that may result in short- and long-term pelvic floor morbidity and a diminished quality of life in young, healthy women. The prevalence of obstetrical anal sphincter injuries ranges from 0.1% to 8.7%. Over recent years, there seems to be a trend of increasing occurrence of obstetrical anal sphincter injuries worldwide. It is unclear why the rates are rising. Previous studies have examined the effect of different risk factors on the prevalence of obstetrical anal sphincter injuries. The change in the incidence of some risk factors for obstetrical anal sphincter injuries can partially explain the overall increase in obstetrical anal sphincter injuries. There is no previous study that explored the impact of the changes of individual risk factors over time on the risk for obstetrical anal sphincter injuries.

OBJECTIVE

The main aim of this study was to examine the temporal trends in the prevalence and odds ratio of the major risk factors known to be associated with obstetrical anal sphincter injuries in the period from 1988 to 2016.

STUDY DESIGN

This was a retrospective cohort study that included all women who underwent vaginal deliveries between 1988 and 2016 at a tertiary university medical center. The time intervals were divided into 4 periods (1988-1997, 1998-2007, 2008-2016, and the total time from 1988 to 2016) and the incidence of each risk factor was calculated for each time period. Correlation models and regression analysis were performed to examine the association between obstetrical anal sphincter injuries and the different risk factors over time. Furthermore, the trends in the odds ratios of the important risk factors over the time periods were evaluated using a multivariate regression analysis in which the primiparous women were separated from the multiparous women.

RESULTS

During the study period, there were 295,668 vaginal deliveries. Of these, 591 women were diagnosed with obstetrical anal sphincter injuries (0.2%). The significant risk factors for obstetrical anal sphincter injuries (P<.05) in the multivariable analysis were the following: primiparity, vaginal birth after cesarean delivery, vacuum extraction, and a birthweight of >4 kg. There was a significant (P<.05) increase in the incidence over the study period for the following risk factors: primiparity, vaginal birth after cesarean delivery, and vacuum extraction. No change was found in the incidence of the risk factor of a birthweight of >4 kg. In addition, we found a strengthening of the association between vaginal birth after cesarean delivery and macrosomia with obstetrical anal sphincter injuries, as opposed to a decline in the relative contribution of vacuum extraction to the overall risk for obstetrical anal sphincter injuries. Moreover, we found that obstetrical anal sphincter injuries among primiparous women increased 7-fold over the study period but was unchanged among multiparous women.

CONCLUSION

We have shown significant (P<.05) temporal trends in the incidence and odds ratio of some of the known risk factors for obstetrical anal sphincter injuries. A better understanding of the changes in the incidence and specific contribution of important risk factors for obstetrical anal sphincter injuries may explain, in part, the worldwide increase in the prevalence of this important and detrimental complication of vaginal birth.

The association between vacuum-assisted vaginal delivery and anal sphincter injury

INTRODUCTION

Vacuum-assisted vaginal delivery (VAVD) is considered a major risk factor for obstetric anal sphincter injuries (OASIS). However, it is difficult to estimate its true contribution to the occurrence of OASIS, as its performance may be confounded by other determinants. Therefore, we aimed to evaluate the association of VAVD with OASIS among primiparous women compared to SVD.

METHODS

A retrospective cohort study including all primiparous women who vaginally delivered a cephalic singleton gestation during the years 2011 to 2020. As VAVDs were not performed before 34 gestational weeks, we capped the cohort at this gestational age. Women were allocated into two groups: VAVDs and spontaneous vaginal deliveries (SVD). We compared women with OASIS to those without and performed a multivariate analysis including factors that were found significant in the univariate analysis. We further divided the whole cohort into different subcategories. The primary outcome was the rate of OASIS in VAVD compared to SVD.

RESULTS

Overall, 23,272 primiparous vaginal deliveries were available for evaluation. Of these, 3595 delivered by VAVD and 19,677 delivered spontaneously. OASIS occurred in 421 (1.8%) of the deliveries. OASIS were more common in VAVDs than in SVDs [83 (2.3%) vs. 338 (1.7%), respectively, OR (95% CI) 1.35 (1.06-1.72), p = 0.01]. After multivariate regression analysis, OASIS were not found to be independently associated with the mode of delivery [aOR 1.21 (95% CI) 0.88-1.68, P = 0.23]. In a categorical analysis of OASIS rates by risk factors and mode of delivery, VAVD was not associated with an increase in OASIS among women giving birth to neonates weighing > 3500 g compared to SVD [OR (95% CI) 1.02 (0.65-1.62), P = 0.90].

CONCLUSION

Among primiparous women VAVD did not increase the risk of OASIS compared to SVD.