Risk factors and outcomes in "well-selected" vaginal breech deliveries: a retrospective observational study

Mechanics of vaginal breech birth: Factors influencing obstetric maneuver rate, duration of active second stage of labor, and neonatal outcome

BACKGROUND

We investigated possible parameters that could predict the need for obstetric maneuvers, the duration of the active second stage of labor (i.e., the duration of active pushing), and short-term neonatal outcome in vaginal breech births.

MATERIALS AND METHODS

We performed a retrospective analysis of 268 successful singleton vaginal breech births in women without previous vaginal births from January 2015 to August 2022. Multivariable regression was used to investigate associations between maternal and fetal characteristics (including antepartum magnetic resonance (MR) pelvimetry) with obstetric maneuvers, the duration of active second stage of labor, pH values, and admission to the neonatal unit. Models for the prediction of obstetric maneuvers were built and internally validated.

RESULTS

Obstetric maneuvers were performed in a total of 130 women (48.5%). A total of 32 neonates (11.9%) had to be admitted to the neonatal unit. The intertuberous distance (ITD) (p < 0.001), epidural analgesia (p < 0.001), and birthweight (p = 0.026) were associated with the duration of active second stage of labor. ITD (p = 0.028) and birthweight (p = 0.011) were also independently associated with admission to the neonatal unit, while pH values below 7.10 dropped significantly (p = 0.0034) if ITD was ≥13 cm. Furthermore, ITD (p < 0.001) and biparietal diameter (p = 0.002) were independent predictors for obstetric maneuvers.

CONCLUSIONS

ITD is independently associated with the duration of active second stage of labor. Thus, it can predict suboptimal birth mechanics in the last stage of birth, which may lead to the need for obstetric maneuvers, lower arterial pH values, and admission to the neonatal unit. Consequently, MR pelvimetry gives additional information for practitioners and birthing people preferring a vaginal breech birth.

Retrospective Analysis of Pregnancy Outcomes Following External Cephalic Version for Breech Presentation

Objective

We explored the feasibility and safety of external cephalic version (ECV) for cases of breech presentation.

Methods

We retrospectively analyzed data from 158 singleton pregnant women with breech presentation at 36 weeks gestation, admitted to Guangzhou Hospital of Integrated Traditional and Western Medicine from January 2018 to March 2022. 42 underwent ECV, categorized as the ECV group, while 116 without ECV comprised the control group. Systematic collection and evaluation of pregnancy outcomes were conducted for both groups.

Results

Within the control group, 16 cases experienced a spontaneous transition to head presentation, among which 14 cases resulted in successful vaginal deliveries. In 2 cases, cesarean deliveries were performed due to fetal macrosomia and persistent posterior occipital presentation. Furthermore, 2 cases of breech presentation in pregnant women were successfully delivered vaginally through breech traction, necessitating an emergency procedure due to the wide opening of the uterus. Within the ECV group, 28 cases were successfully inverted to the cephalic presentation. Among them, 1 case underwent an emergency cesarean delivery due to fetal distress during cephalic delivery, 3 cases required cesarean deliveries due to abnormal labor, and 24 cases were successfully delivered vaginally. The comparative analyses showed that the cesarean section rate (18/42 vs 100/116) and non-cephalic delivery rate (14/42 vs 100/116) in the ECV group were significantly lower than those in the control group (P < 0.001). There was no statistically significant differences between the two groups with respect to the rate of newborns with Apgar score < 7 (1/42 vs 3/116), premature rupture of membrane (3/42 vs 20/116), acute fetal distress (2/42 vs 2/116), and cord prolapse (0/42 vs 1/116) (P > 0.05).

Conclusion

ECV can effectively reduce the rate of cesarean delivery and non-cephalic deliveries. However, it but requires strict adherence to indications and continuous monitoring.

Birth injury in breech delivery: a nationwide population-based cohort study in Finland

PURPOSE

Previous studies have examined the optimal mode of breech delivery extensively, but there is a scarcity of publications focusing on the birth injuries of neonates born in breech presentation. This study aimed to examine birth injury in breech deliveries.

METHODS

In this retrospective register-based nationwide cohort study, data on birth injuries in vaginal breech deliveries with singleton live births were compared to cesarean section with breech presentation and cephalic vaginal delivery between 2004 and 2017 in Finland. The data were retrieved from the National Medical Birth Register. Primary outcome variables were severe and mild birth injury. Incidences of birth injuries in different gestational ages and birthweights were calculated in different modes of delivery. Crude odds ratios of risk factors for severe birth injury were analyzed.

RESULTS

In vaginal breech delivery (n = 4344), there were 0.8% of neonates with severe birth injury and 1.5% of neonates with mild birth injury compared to 0.06% and 0.2% in breech cesarean section (n = 16,979) and 0.3% and 1.9% in cephalic vaginal delivery (n = 629,182). Brachial plexus palsy was the most common type of injury in vaginal breech delivery. Increasing gestational age and birthweight had a stronger effect on the risk for injury among cephalic vaginal deliveries than among vaginal breech deliveries.

CONCLUSION

Birth injuries were rare in vaginal breech deliveries. The incidence of severe birth injury was two times higher in vaginal breech delivery compared to cephalic vaginal delivery. Brachial plexus palsy was the most common type of injury in vaginal breech delivery.

Neonatal Birth Trauma: Analysis of Yearly Trends, Risk Factors, and Outcomes

OBJECTIVE

To evaluate the trends, proportions, risk factors, resource utilization, and outcomes of neonatal birth trauma in the US.

STUDY DESIGN

This cross-sectional study of in-hospital births used the Nationwide Inpatient Sample for 2006-2014. We divided the cases by type of birth trauma: scalp injuries and major birth trauma. Linear regression for yearly trends and logistic regression were used for risk factors and outcomes. A generalized linear model was used, with a Poisson distribution for the length of stay and a gamma distribution for total spending charges.

RESULTS

A total of 982 033 weighted records with neonatal birth trauma were found. The prevalence rate increased by 23% from (from 25.3 to 31.1 per 1000 hospital births). Scalp injuries composed 80% of all birth traumas and increased yearly from 19.87 to 26.46 per 1000 hospital births. Major birth trauma decreased from 5.44 to 4.67 per 1000 hospital births due to decreased clavicular fractures, brachial plexus injuries, and intracranial hemorrhage. There were significant differences in demographics and risk factors between the 2 groups. Compared with scalp injuries, major birth trauma was associated with higher odds of hypoxic-ischemic encephalopathy, seizures, need for mechanical ventilation, meconium aspiration, and sepsis. Length of stay was increased by 56%, and total charges were almost doubled for major birth trauma.

CONCLUSIONS

Neonatal birth trauma increased over the study period secondary to scalp injuries. Major birth trauma constitutes a significant health burden. Scalp injuries are also associated with increased morbidity and might be markers of brain injury in some cases.

Risk factors for adverse outcomes in vaginal preterm breech labor

PURPOSE

To assess the risk factors for adverse outcomes in attempted vaginal preterm breech deliveries.

METHODS

A retrospective case-control study, including 2312 preterm breech deliveries (24 + 0 to 36 + 6 gestational weeks) from 2004 to 2018 in Finland. The preterm breech fetuses with adverse outcomes born vaginally or by emergency cesarean section were compared with the fetuses without adverse outcomes with the same gestational age. A multivariable logistic regression analysis was used to calculate the risk factors for adverse outcomes (umbilical arterial pH below 7, 5-min Apgar score below 4, intrapartum stillbirth and neonatal death < 28 days of age).

RESULTS

Adverse outcome in vaginal preterm breech delivery was associated with maternal obesity (aOR 32.19, CI 2.97-348.65), smoking (aOR 2.29, CI 1.12-4.72), congenital anomalies (aOR 4.50, 1.56-12.96), preterm premature rupture of membranes (aOR 1.87, CI 1.00-3.49), oligohydramnios (28-32 weeks of gestation: aOR 6.50, CI 2.00-21.11, 33-36 weeks of gestation: aOR 19.06, CI 7.15-50.85), epidural anesthesia in vaginal birth (aOR 2.44, CI 1.19-5.01), and fetal growth below the second standard deviation (28-32 weeks of gestation: aOR 5.89, CI 1.00-34.74, 33-36 weeks of gestation: aOR 12.27, CI 2.81-53.66).

CONCLUSION

The study shows that for each subcategory of preterm birth, there are different risk factors for adverse neonatal outcomes in planned vaginal breech delivery. Due to the extraordinary increased risk of adverse outcomes, we would recommend a planned cesarean section in very preterm breech presentation (28 + 0 to 32 + 6 weeks) with severe maternal obesity, oligohydramnios, or fetal growth restriction and in moderate to late preterm breech presentation (33 + 0 to 36 + 6 weeks) with oligohydramnios or fetal growth restriction.

Revisiting the management of term breech presentation: a proposal for overcoming some of the controversies

Background

The debate surrounding the management of term breech presentation has excessively focused on the mode of delivery. Indeed, a steady decline in the rate of vaginal breech delivery has been observed over the last three decades, and the soundness of the vaginal route was seriously challenged at the beginning of the 2000s. However, associations between adverse perinatal outcomes and antenatal risk factors have been observed in foetuses that remain in the breech presentation in late gestation, confirming older data and raising the question of the role of these antenatal risk factors in adverse perinatal outcomes. Thus, aspects beyond the mode of delivery must be considered regarding the awareness and adequate management of such situations in term breech pregnancies.

Main body

In the context of the most recent meta-analysis and with the publication of large-scale epidemiologic studies from medical birth registries in countries that have not abruptly altered their criteria for individual decision-making regarding the breech delivery mode, the currently available data provide essential clues to understanding the underlying maternal-foetal conditions beyond the delivery mode that play a role in perinatal outcomes, such as foetal growth restriction and gestational diabetes mellitus. In view of such data, an accurate evaluation of these underlying conditions is necessary in cases of persistent term breech presentation. Timely breech detection, estimated foetal weight/growth curves and foetal/maternal well-being should be considered along with these possible antenatal risk factors; a thorough analysis of foetal presentation and an evaluation of the possible benefit of external cephalic version and pelvic adequacy in each specific situation of persistent breech presentation should be performed.

Conclusion

The adequate management of term breech pregnancies requires screening and the efficient identification of breech presentation at 36 weeks of gestation, followed by thorough evaluations of foetal weight, growth and mobility, while obstetric history, antenatal gestational disorders and pelvis size/conformation are considered. The management plan, including external cephalic version and follow-up based on the maternal/foetal condition and potentially associated disorders, should be organized on a case-by-case basis by a skilled team after the woman is informed and helped to make a reasoned decision regarding delivery route.

Risk factors associated with adverse perinatal outcome in planned vaginal breech labors at term: a retrospective population-based case-control study

BACKGROUND

Vaginal breech delivery is associated with adverse perinatal outcome. The aim of this study was to identify factors associated with adverse perinatal outcome in term breech pregnancies, and to provide clinicians an aid in selecting women for a trial of vaginal labor with the fetus in breech position.

METHODS

We conducted a retrospective, nationwide, Finnish population-based case-control study. All planned singleton vaginal deliveries at term with the fetus in breech position between the years 2005 and 2014 were analyzed. The study's end point was a composite set of adverse perinatal outcomes. All infants with an adverse outcome were compared to the infants with normal outcomes. A multivariate logistic regression model was used to analyze the data.

RESULTS

An adverse perinatal outcome was recorded for 73 (1.5%) infants. According to the study results fetal growth restriction (adjusted odds ratio, 2.94; 95% CI, 1.30-6.67), oligohydramnios (adjusted odds ratio, 2.94; 95% CI, 1.15-7.18), a history of cesarean section (adjusted odds ratio, 2.94; 95% CI, 1.28-6.77, gestational diabetes (adjusted odds ratio, 2.89; 95% CI, 1.54-5.40), epidural anesthesia (adjusted odds ratio, 2.20; 95% CI, 1.29-3.75) and nulliparity (adjusted odds ratio, 1.84; 95% CI, 1.10-3.08) were associated with adverse perinatal outcome.

CONCLUSIONS

Adverse perinatal outcome in planned vaginal breech labor at term is associated with fetal growth restriction, oligohydramnios, previous cesarean delivery, gestational diabetes, nulliparity and epidural anesthesia.

Obstetric and Anesthetic Approaches to External Cephalic Version

Breech presentation is the most common abnormal fetal presentation and complicates approximately 3% to 4% of all pregnancies. External cephalic version (ECV) should be recommended to women with a breech singleton pregnancy, if there is no maternal or fetal contraindication. ECV increases the chance of cephalic presentation at the onset of labor and decreases the rate of cesarean delivery by almost 40%. The success rate of ECV is approximately 60%. Review of the risks and benefits for performing an ECV and for both the timing of ECV and the number of attempts should be should be discussed with the patient.

Breech presentation at term and associated obstetric risks factors-a nationwide population based cohort study

PURPOSE

The aim of this study was to estimate whether breech presentation at term was associated with known individual obstetric risk factors for adverse fetal outcome.

METHODS

This was a retrospective, nationwide Finnish population-based cohort study. Obstetric risks in all breech and vertex singleton deliveries at term were compared between the years 2005 and 2014. A multivariable logistic regression model was used to determine significant risk factors.

RESULTS

The breech presentation rate at term for singleton pregnancies was 2.4%. The stillbirth rate in term breech presentation was significantly higher compared to cephalic presentation (0.2 vs 0.1%). The odds ratios (95% CIs) for fetal growth restriction, oligohydramnios, gestational diabetes, a history of cesarean section and congenital fetal abnormalities were 1.19 CI (1.07-1.32), 1.42 CI (1.27-1.57), 1.06 CI (1.00-1.13), 2.13 (1.98-2.29) and 2.01 CI (1.92-2.11).

CONCLUSIONS

The study showed that breech presentation at term on its own was significantly associated with antenatal stillbirth and a number of individual obstetric risk factors for adverse perinatal outcomes. The risk factors included oligohydramnios, fetal growth restriction, gestational diabetes, history of caesarean section and congenital anomalies.