Pregnancy outcomes by mode of delivery among breech births

Effect of mode of delivery on perinatal outcome in severe preterm birth: systematic review and meta-analysis

OBJECTIVE

To review the evidence on the effect of mode of delivery on perinatal outcome of fetuses born before 32 weeks' gestation.

METHODS

MEDLINE, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), the ClinicalTrials.gov registry and gray literature sources were searched, starting from the year 2000 to reflect contemporary practice in perinatal care. Non-randomized or randomized studies that included singleton fetuses without chromosomal abnormality or major congenital defect delivered vaginally or via Cesarean section were eligible for inclusion in the analysis. Primary outcomes were neonatal death, defined as death in the first 28 days of age, and survival to discharge. Secondary outcomes were other adverse perinatal events. The ROBINS-I tool was used to assess the risk of bias. The overall quality of evidence for the outcomes was assessed according to GRADE. Summary odds ratios (ORs) with 95% CIs were calculated, and random-effects models were used for data synthesis. Subgroup analysis was performed for delivery before 28 weeks, delivery between 28 and 32 weeks and according to fetal presentation at delivery.

RESULTS

A total of 27 retrospective studies (22 887 neonates) were included in the systematic review and meta-analysis, all of which reported on singleton pregnancies. Among cases born before 28 weeks, vaginal delivery significantly increased the risk of neonatal death of fetuses with any type of presentation (n = 1496) (OR 1.87 (95% CI, 1.05-3.35); I2  = 65%, very low quality of evidence) and of fetuses with breech presentation (n = 733) (OR 3.55 (95% CI, 2.42-5.21); I2  = 21%, moderate quality of evidence). The odds of survival to discharge were significantly decreased among fetuses with breech presentation delivered before 28 weeks (n = 646) (OR 0.36 (95% CI, 0.24-0.54); I2  = 21%, low quality of evidence). Among breech fetuses born between 28 and 32 weeks, vaginal delivery increased the odds of perinatal death (intrapartum and neonatal) (n = 1581) (OR 3.06 (95% CI, 1.47-6.35); I2  = 0%, high quality of evidence). In non-cephalic fetuses born between 24 and 32 weeks, vaginal delivery decreased the odds of survival to discharge (n = 1030) (OR 0.28 (95% CI, 0.19-0.40); I2  = 0%, moderate quality of evidence). No significant effect on mortality of mode of delivery was observed in cephalic fetuses at any gestational age.

CONCLUSIONS

This systematic review and meta-analysis suggests that vaginal delivery in severe preterm birth is associated with an increased risk of neonatal and perinatal death in breech fetuses, while no significant association was observed for cephalic fetuses. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

What to do when it is breech? A state-of-the-art review on management of breech presentation

Any non-cephalic presentation in a fetus is regarded as malpresentation. The most common malpresentation, breech, contributes to 3%-5% of term pregnancies and is a leading indication for cesarean delivery. Identification of risk factors and a proper physical examination are beneficial; however, ultrasound is the gold standard for the diagnosis of malpresentations. External cephalic version (ECV) refers to a procedure aimed to convert a non-cephalic presenting fetus to cephalic presentation. This procedure is performed manually through the mother’s abdomen by a trained health care provider, to reduce the likelihood of a cesarean section. Studies have reported a version success rate of above 50% by ECV. The main objective of this review is to present a broad perspective on fetal malpresentation, ECV, and delivery of a breech fetus. The focus is to elaborate all clinical scenarios of breech and to provide an evidence-based clinical approach for them. After discussing breech prevalence, risk factors, diagnosis, and management, an updated review of ECV is presented. Moreover, ECV indications/contraindications, alternatives, clinical techniques on how to perform ECV and breech vaginal delivery, and obstetrical considerations for the delivery of malpresentations are thoroughly discussed.

Neonatal outcome in vaginal breech labor at 32 + 0-36 + 0 weeks of gestation: a nationwide, population-based record linkage study

Background

In many countries, vaginal breech labor at term is an option in selected cases. However, the safety of vaginal breech labor in preterm is still unclear. Therefore our study aimed to evaluate the safety of vaginal breech labor in late preterm deliveries.

Design

A retrospective register-based study.

Setting

Maternity hospitals in Finland, 2004–2017.

Participants

The study population included 762 preterm breech deliveries at 32 + 0—36 + 6 gestational weeks according to the mode of delivery, 535 (70.2%) of them were born vaginally in breech presentation, and 227 (29.8%) were delivered by non-urgent cesarean section.

Methods

The study compared short-term neonatal adverse outcomes of singleton vaginal breech deliveries with non-urgent cesarean deliveries at 32 + 0 to 36 + 6 weeks of gestation. An odd ratio with 95% confidence intervals was calculated to estimate the relative risk of adverse outcomes.

Outcome measures

Neonatal death, an arterial umbilical pH below seven, a five-minute Apgar score below four and seven, admission to neonatal intensive care unit, neonatal intubation, neonatal antibiotic therapy, neonatal birth trauma, respiratory distress syndrome, neonatal convulsions, cerebral ischemia, hypoxic-ischemic encephalopathy, congenital hypotonia, and a composite of severe adverse outcomes.

Results

A five-minute Apgar scores below seven were increased in vaginal breech labor at 32 + 0 to 36 + 6 weeks of gestation compared to non-urgent cesarean sections (aOR 2.48, 95% CI 1.08–5.59). Neonatal antibiotic therapy, the admission to neonatal intensive care unit, and neonatal respiratory distress syndrome were decreased after vaginal breech labor compared to the outcomes of non-urgent cesarean section (neonatal antibiotic therapy aOR 0.60, 95% CI 0.40–0.89; neonatal NICU admission aOR 0.47, 95% CI 0.33–0.68; respiratory distress syndrome aOR 0.30, 95% CI 0.19–0.48).

Conclusion

Vaginal breech labor at 32 + 0—36 + 6 gestational weeks does not increase severe neonatal short-term morbidity or mortality compared to cesarean section.

Maternal and neonatal outcomes in the following delivery after previous preterm caesarean breech birth: a national cohort study

The objective of this retrospective, nationwide Finnish population-based cohort study was to determine whether there is an association between preterm caesarean breech delivery in the first pregnancy and maternal and neonatal morbidity in the subsequent pregnancy and delivery. We identified all singleton preterm breech birth in Finland from 2000 to 2017 (n = 1259) and constructed a data set of the first two deliveries for these women. We compared outcomes of the following pregnancy and delivery among women with a previous preterm caesarean breech section with the outcomes of women with one previous vaginal preterm breech birth. p Value, odds ratio, and adjusted odds ratio were calculated. Neonates of women with a previous caesarean preterm breech delivery had an increased risk for arterial umbilical cord pH below seven (1.2% versus 0%; p value .024) and a higher rate of neonatal intensive care unit admission [22.9% versus 15% adjusted OR 1.57 (1.13-2.18); p value <.001]. The women with a previous caesarean section had a higher rate of uterine rupture (2.3% versus 0%; p value .001). They were also more likely in the subsequent pregnancy to have a planned caesarean section [19.9% versus 4% adjusted OR 8.55 (4.58-15.95), an emergency caesarean section [21.5% versus 9.7% adjusted OR 2.16 (1.28-2.18)], or an instrumental vaginal delivery [9.3% versus 3.8% adjusted OR 2.38 (1.08-5.23)].IMPACT STATEMENTWhat is already known on this subject? Vaginal birth after caesarean section is generally known to be associated with a higher risk of maternal and neonatal morbidity.What do the results of this study add? The following birth after previous caesarean preterm breech section is associated with a higher rate of uterine rupture and with a higher rate neonatal admission to the neonatal intensive care unit and more often an arterial umbilical cord pH below seven regardless of the mode of the following delivery, compared to women with a subsequent delivery after a previous vaginal preterm breech birth.What are the implications of these findings for clinical practice and/or further research? Our results must be considered when counselling patients regarding their first preterm breech delivery, as the selected method of delivery also affects the outcomes of subsequent pregnancies and deliveries.

Comparison of maternal and fetal complications in pregnant women with breech presentation undergoing spontaneous or induced vaginal delivery, or cesarean delivery

OBJECTIVE

Breech presentation is the most common form of malpresentation, and associated with perinatal asphyxia and mortality, and maternal morbidity. Data associated with labor induction in breech presentation are limited. The aim of this study was to compare maternal and fetal complication rates in induced and spontaneous vaginal, and cesarean delivery with breech presentation.

MATERIALS AND METHODS

Pregnant women with breech presentation were grouped: spontaneous vaginal delivery (Group 1, n = 72) induced or augmented vaginal delivery (Group 2, n = 32), and cesarean delivery (Group 3, n = 253). Fetal complications were as follows: clavicle fracture, femur fracture, humerus fracture, brachial plexus injury, cephalic hematoma, pneumothorax, need for intensive care unit (ICU), and 5th minute APGAR <7. Maternal complications were as follows: vaginal hematoma, deep vaginal laceration, perineal injury (≥3rd degree), decline in hemoglobin level (>2 g/dL), and postpartum endometritis. Data were collected and analyzed retrospectively.

RESULTS

The highest fetal complication rate was in Group 2, and the lowest in Group 3 (p = 0.001). Clavicle fracture was significantly less in Group 3 compared with the other groups (p = 0.024). The rate of lower APGAR scores at the 5th minute was similar in all groups. Maternal complications were significantly higher in Group 2 compared with the other groups (p = 0.001). Fetal complications were 5.66-fold higher in Group 1 than in Group 3 (p = 0.002). Fetal and maternal complications were 9.48-fold and 7.48-fold higher, respectively, in Group 2 than in Group 3 (p < 0.001).

CONCLUSION

This study is the first in literature to have investigated and analyzed neonatal complications in breech delivery according to different delivery modes including induced vaginal delivery. Due to possible complications, the risks and benefits of a specific type of delivery should be considered in breech presentation.

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.

Impact of the mode of delivery on maternal and neonatal outcome in spontaneous-onset breech labor at 32+0-36+6 weeks of gestation: A retrospective cohort study

OBJECTIVE

To compare neonatal and maternal outcomes in spontaneously onset preterm breech deliveries after trial of labor (BTOL) and intended cesarean section (BCS), and between BTOL and vertex control deliveries, in singleton fetuses at 32⁺⁰-36⁺⁶ weeks of gestation.

STUDY DESIGN

Retrospective single center cohort study in a Finnish University Hospital including all spontaneous-onset preterm breech deliveries with 32 completed gestational weeks in 2003-2015. The study population comprised a total of 176 preterm breech and 103 vertex control deliveries, matched by gestational age and whether the mother had given birth vaginally before or not. Infants with severe malformations and antepartum fetal distress were excluded. Subgroup analyses were made in two cohorts according to gestational age. Main outcome measures were maternal and neonatal mortality and morbidity, low cord pH and Apgar score.

RESULTS

No mortality was observed, and severe morbidity was rare. No difference in incidence of low cord pH or five-minute Apgar score was observed between the groups. Apgar scores at the age of one minute were comparable in the breech groups but more often low in the BTOL group compared to the vertex control group. 16.5% of neonates in the BTOL group, 23.3% in the BCS group and 7.8% in the vertex group needed intensive care. In logistic regression analysis, lower gestational age and being small for gestational age were associated with the need for neonatal intensive care. Being allowed a trial of labor was not associated with the need for neonatal intensive care. Maternal morbidity was similar across the groups, but median blood loss was more pronounced in the BCS group compared to the BTOL group.

CONCLUSION

In breech deliveries at 32⁺⁰-36⁺⁶ gestational weeks, trial of labor did not increase neonatal morbidity compared to intended cesarean delivery. Infants born after a trial of labor in breech presentation display low one-minute Apgar score and need intensive care more often compared to vertex controls.

Comparison of cesarean versus vaginal delivery of extremely preterm gestations in breech presentation: retrospective cohort study

Objective: As survival increases at earlier gestational ages, the optimal mode of delivery, especially in cases of breech presentation, is of increasing importance. The objective of this study was to compare outcomes of vaginal delivery (VD) and cesarean section (CS) births for infants in breech presentation at borderline viability. Study design: A retrospective chart review of live breech births between 23 + 0 and 25 + 6 weeks gestation at a tertiary university center from 2003 to 2013 was conducted. Those delivered vaginally were compared with those delivered by CS. Stillbirths and deliveries where no resuscitation was intended were removed from the analysis. Variables were compared using a Student t-test (continuous), Mann-Whitney U test (categorical), or a Chi-squared test (count). Logistic regression analysis was performed to further evaluate the results. Results with p < .05 were considered significant. Results: One hundred seventy-six births were included, 36 VD and 140 CS. Baseline characteristics were similar between groups. Gestational age at delivery was significantly higher in CS deliveries (24.9 ± 0.6 versus 24.5 ± 0.7, p = .0007). The rate of neonatal death (23.6% versus 44.4%, p = .0127) was significantly lower in those born by CS. All other neonatal outcomes including Apgar scores at one and 5 min, cord gases, birth weight, length of stay in NICU, incidence of respiratory complications, and incidence of high-grade IVH demonstrated no significant differences. Logistic regression suggested that male sex, lower birth weight, and earlier gestational age are significantly associated with neonatal mortality. Thirty percent of uterine incisions were of the classical, high transverse or inverted-T types. The estimated blood loss was significantly higher in CS births (706.6 ± 226.4 versus 327.4 ± 174.1 mL, p < .0001), but there was no difference in the rate of blood transfusion. Conclusion: CS delivery of breech infants at borderline viability had a protective effect on neonatal mortality compared to VD depending on the regression model utilized. Infant sex, birth weight, and gestational age also contribute significantly to neonatal mortality. A prospective study of planned method of delivery is recommended to further explore this finding.

What is the safest mode of birth for extremely preterm breech singleton infants who are actively resuscitated? A systematic review and meta-analyses

BACKGROUND

The safest delivery mode of extremely preterm breech singletons is unknown.

OBJECTIVES

To determine safest delivery mode of actively resuscitated extremely preterm breech singletons.

SEARCH STRATEGY

We searched Cochrane CENTRAL, MEDLINE, EMBASE, CINAHL and ClinicalTrials.gov from January 1994 to May 2017.

SELECTION CRITERIA

We included studies comparing outcomes by delivery mode in actively resuscitated breech infants between 23⁺⁰ and 27⁺⁶ weeks.

DATA COLLECTION AND ANALYSIS

We synthesised data using random effects, generated odds ratios, 95% confidence intervals and number-needed-to-treat (NNT). Our primary outcomes were death (neonatal, before discharge, or by 6 months) and severe intraventricular haemorrhage (grades III/IV), stratified by gestational age (23⁺⁰ -24⁺⁶ , 25⁺⁰ -26⁺⁶ , 27⁺⁰ -27⁺⁶ weeks).

MAIN RESULTS

We included 15 studies with 12 335 infants. We found that caesarean section was associated with a 41% decrease in odds of death between 23⁺⁰ and 27⁺⁶ weeks [odds ratio (OR) 0.59, 95% CI 0.36-0.95, NNT 8], with the greatest decrease at 23⁺⁰ -24⁺⁶ weeks (OR 0.58, 95% CI 0.44-0.75, NNT 7). The OR at 25⁺⁰ -26⁺⁶ and 27⁺⁰ -27⁺⁶ weeks were 0.72 (95% CI 0.34-1.52) and 2.04 (95% CI 0.20-20.62), respectively. We found that caesarean section was associated with 49% decrease in odds of severe intraventricular haemorrhage between 23⁺⁰ and 27⁺⁶ weeks (OR 0.51, 95% CI 0.29-0.91, NNT 12), whereas the OR at 25⁺⁰ -26⁺⁶ and 27⁺⁰ -27⁺⁶ was 0.29 (95% CI 0.07-1.12) and 0.91 (95% CI 0.27-3.05), respectively.

CONCLUSIONS

Caesarean section was associated with reductions in the odds of death by 41% and of severe intraventricular haemorrhage by 49% in actively resuscitated breech singletons < 28 weeks of gestation. The data are mostly observational, which may be inherently biased, and scarce on other morbidities, necessitating thorough discussion between parents and clinicians.

TWEETABLE ABSTRACT

Caesarean section associated with lower odds of death and severe intraventricular haemorrhage in actively resuscitated breech singletons <28 weeks.

Maternal complications associated with stillbirth delivery: A cross-sectional analysis

This study sought to identify delivery complications associated with stillbirth labour and delivery. We conducted a retrospective chart review evaluating stillbirth demographics, pregnancy and maternal risk factors, and complications of labour and delivery. We performed bivariable analysis and multivariable logistic regression to evaluate factors associated with medical complications and variations by race. Our cohort included 543 mothers with stillbirth, of which two-thirds were African-American. We noted high rates of shoulder dystocia, clinical chorioamnionitis, postpartum haemorrhage and retained placenta in women with stillbirths. Thirty-three women (6%) experienced at least one serious maternal complication. Complication rates did not vary by maternal race. Providers who perform obstetrical care should be alert to the high rate of maternal medical complications associated with labour and delivery of a stillbirth foetus.

Maternal experiences of vaginal breech delivery

BACKGROUND

The optimal mode of breech birth remains controversial. In Finland, a trial of vaginal delivery is possible if strict selection criteria are met. As clinical practice in managing vaginal breech birth differs from that in normal delivery, the birth experience may also be different. This cohort study compares the childbirth experience between term breech and vertex deliveries.

METHODS

Intended vaginal term breech births from 2008 to October 2012 were included, and for every breech delivery, a vertex control was selected. The proportions of deliveries ending in a cesarean section and of mothers who had given birth vaginally before were equal in both groups. Three hundred eight mothers were sent the childbirth experience questionnaire and 170 returned it.

RESULTS

The birth experience does not differ between breech and vertex births, except for aspects with respect to the choice of birthing position. Indications of an even more positive experience were observed in the breech group, with the exception of the choice of analgesia, but these were not statistically significant. Primiparity, emergency cesarean section, infant birth trauma and prolonged hospital stay were identified as risk factors for a negative birth experience.

CONCLUSION

The birth experience of vaginal breech birth seems to be at least as positive as the vaginal vertex birth experience.

Sonographic weight estimation in fetuses with breech presentation

PURPOSE

To assess the accuracy of weight estimation (WE) in fetuses with breech presentation and to compare it directly with a control group of fetuses in vertex presentation.

MATERIALS AND METHODS

In a retrospective cohort study, the accuracy of WE in fetuses with breech presentation (n = 244) was evaluated using eight sonographic models and was compared with a control group of fetuses in vertex presentation (n = 244). Each fetus underwent ultrasound examination with complete biometric parameters within 7 days before delivery. The accuracy of the different formulas was compared using means of percentage error (MPE), a measure that reflects systematic error; standard deviation values of MPEs, a measure for random error; medians of absolute percentage error (MAPE), which take both the systematic and random error into account and the percentage of fetal WEs falling within a 10 % range of the actual birth weight.

RESULTS

Significantly lower (more negative) MPE values were found in the breech group with the Hadlock (AC, FL) formula, whereas no significant differences were seen with any of the other equations. When compared to zero, in the breech group, a significant systematic error was found with five formulas, while in the control group a significant systematic error was found with three equations. With regard to random error and MAPE, no significant differences were found between the two groups, irrespective of the formula applied. Generally, in both groups, formulas based on three or four biometric indices were more accurate in detecting fetal weight than formulas with only one or two parameters.

CONCLUSIONS

Weight estimation in fetuses with breech presentation was as accurate as weight estimation in fetuses with vertex presentation. Using the currently available, well-established formulas should therefore also be appropriate for WE in fetuses with such malpresentations.

Caesarean section for preterm birth and, breech presentation and twin pregnancies

Caesarean section incidence is steadily rising worldwide; the major contributor to this rise is pregnancies with previous caesarean section. Hence, it is important to scrutinise carefully the indication of primary caesarean sections. Preterm births, breech presentation and twin pregnancies together complicate 12-18% of all births. The role of caesarean section in these pregnancies is controversial and lacks good evidence-based guidelines. Policy on mode of delivery in these three important obstetric groups is bound to influence overall primary caesarean section rates. In this chapter, we review the evidence on the place of caesarean delivery in these three important groups.