Hyperextension of the fetal head in breech presentation. A study with long-term follow-up

Contraindications in national guidelines for vaginal breech delivery at term: Comparison, consensus, and controversy

INTRODUCTION

The optimal mode of delivery for vaginal breech presentation remains a clinical dilemma. Planned vaginal delivery offers maternal advantages because it avoids major abdominal surgery and has no consequences for following pregnancies, while elective cesarean delivery proves advantageous for the neonate because adverse outcomes are less frequent. Patient selection for vaginal breech delivery is important based on the individual risk balance. A lack of consensus exists regarding the specific contraindications for vaginal breech delivery, largely due to limited scientific evidence. This systematic review aims to give an overview of contraindications for vaginal breech delivery, as presented in guidelines, analyze relevant literature, and offer evidence-based recommendations for the contraindications stated in the guidelines.

MATERIAL AND METHODS

To identify national guidelines PubMed, the Cochrane Central Register of Controlled Trials, EMBASE, NICE, UpToDate, and ClinicalKey were searched using two keywords: "breech presentation" and "vaginal delivery." We systematically reviewed the literature for existing evidence for contraindications for term vaginal breech delivery. The following databases were searched: PubMed (April 2024), the Cochrane Central Register of Controlled Trials, and EMBASE (1947 to 2024).

RESULTS

Our search identified eight guidelines that stated a total of 11 contraindications for vaginal breech delivery. Among these guidelines, agreement was limited, with the sole consensus in all guidelines on the contraindication of footling breech. Our comprehensive literature search yielded 43 articles discussing 14 potential contraindications. We found supportive evidence for 7 of 11 contraindications from the guidelines, with only substantial and satisfactory evidence for two contraindications.

CONCLUSIONS

The findings of this study underscore the lack of consensus among national guidelines regarding contraindications for term vaginal breech delivery. Furthermore, we found a notable lack of substantial scientific evidence to support these contraindications. In light of these findings, we suggest a reduced list of contraindications in vaginal breech deliveries.

Breech presentation management: A critical review of leading clinical practice guidelines

PROBLEM

Clinical practice guidelines are designed to guide clinicians and consumers of maternity services in clinical decision making, but recommendations are often consensus based and differ greatly between leading organisations.

BACKGROUND

Breech birth is a divisive clinical issue, however vaginal breech births continue to occur despite a globally high caesarean section rate for breech presenting fetuses. Inconsistencies are known to exist between clinical practice guidelines relating to the management of breech presentation.

AIM

The aim of this review was to critically evaluate and compare leading obstetric clinical practice guidelines related to the management of breech presenting fetuses.

METHODS

Leading obstetric guidelines were purposively obtained for review. Analysis was conducted using the International Centre for Allied Health Evidence (iCAHE) Guideline Quality Checklist and reviewing the content of each guideline.

FINDINGS

Antenatal care recommendations and indications for Caesarean Section were relatively consistent between clinical guidelines. However, several inconsistencies were found among the other recommendations in terms of birth mode counselling, intrapartum management and the basis for recommendations.

DISCUSSION

Inconsistencies noted in the clinical practice guidelines have the potential to cause issues related to valid consent and create confusion among clinicians and maternity consumers.

CONCLUSION

Clinical practice guidelines, which focus on the risks of a Vaginal Breech Birth without also discussing the risks of a Caesarean Section when a breech presentation is diagnosed, has the potential to sway clinician attitudes and impact birth mode decision-making in maternity consumers. To respect pregnant women's autonomy and fulfil the legal requirements of consent, clinicians should provide balanced counselling.

Ultrasonographic evidence of persistent hyperextension of the fetal neck: is it a true sign? A diagnostic and prognostic challenge

OBJECTIVE

The purpose of this study was to evaluate the clinical evolution, structural anomalies associated and neonatal outcomes of fetal neck hyperextension in two cases with prenatal ultrasound diagnosis in two different gestational ages.

METHODS

In 2019, two cases of fetal hyperextension came to our attention. Follow-up information was obtained from hospital medical records and obstetrical care providers.

RESULTS

Two woman were investigated in our institution for the presence of fetal abnormalities in the II and III trimester, respectively. In both cases, fetal attitude presented persistent fetal neck hyperextension. One of the two fetuses had a mild ventriculomegaly and suspected for micrognathia. Both had an amniotic fluid increase. One of two had no movement in the lower and upper limbs in ultrasound scans associated with club foot and suspected scoliosis. Both were born by cesarean section with pretty different prognosis: one healthy baby had a retarded psychomotor development and the other one died after 6 months. A precise diagnosis was possible only in one case.

CONCLUSION

The early identification of a fetus with persistent hyperextension of the fetal head should require a detailed ultrasound exam for structural abnormalities and a careful prenatal counseling due to possible postnatal outcome.

[Breech Presentation: CNGOF Guidelines for Clinical Practice - Case Selection for Trial of Labour]

OBJECTIVE

The objective of this chapter is to examine on the basis of the knowledge currently available the criteria available before labour for selecting women who would be eligible for trial of vaginal delivery.

METHODOLOGY

Bibliographical research in French and English using the Medline and Cochrane databases between 1980 and 2019 and the recommendations of international societies.

RESULTS

It is recommended to offer women who wish to attempt a vaginal delivery at term a pelvimetry to decide with them on their mode of delivery (Grade C). The pelvimetric standards used at the time of the PREMODA study were anteroposterior diameter of inlet≥105mm, a transverse diameter of inlet≥120mm, a transverse interspinous diameter≥100mm. However, since there is no evidence about which pelvic measures to use, nor any evidence to set decision-making thresholds other than those set in published studies, the selected decision-making thresholds can be adjusted according to gestational age at delivery or fetal biometrics (Professional consensus). There is no argument for recommending the practice of pelvimetry in the case of delivery before 37 weeks gestational age (Professional consensus) and in the case of breech presentation discovered at the time of beginning of labour, the absence of pelvimetry alone does not contraindicate the attempt of vaginal delivery (Professional consensus). There is insufficient data to recommend the systematic use of fetal weight estimation and/or biparietal diameter measurement as acceptance criteria for a vaginal delivery attempt. In the event of a known fetal weight estimation before birth greater than 3800g, a cesarean section is to be preferred (Professional consensus). The breech presentation is not in itself a contraindication to an attempt of vaginal delivery for a small fetus for gestational age (Professional consensus). The presentation of the non-frank breech is not in itself a contraindication to an attempt of vaginal delivery (Professional consensus). In the case of premature breech delivery, current data do not allow to recommend one delivery route over another (Professional consensus). It is recommended to check the absence of hyperextension of the fetal head by ultrasound before an attempt of vaginal delivery (Professional consensus) and to prefer a cesarean section if such a position is found (Professional consensus). It is not recommended to propose a caesarean section with the sole reason of nulliparity (Grade C). The history of cesarean section is not in itself a contraindication to an attempt of vaginal delivery in the case of fetal breech presentation (Professional consensus). Premature rupture of the membranes is not in itself a contraindication to an attempt of vaginal delivery (Professional consensus).

CONCLUSION

A number of the factors analyzed in this chapter are to be incorporated into the decision-making process in order to choose with the woman whose fetus is in breech presentation the delivery route.

Fetal cervical hyperextension in arthrogryposis

Perhaps the most dramatic position of a newborn after delivery is when there is hyperextension of the neck and spine. It will have been presented in utero and today, almost always, such babies will have been delivered by C-section. The associated anomalies are variable. The process(es) that can lead to cervical hyperextension is/are largely unknown. The outcome is variable from lethal to completely resolve. Individuals with arthrogryposis and in particular with Amyoplasia appear to have an increased frequency of neck, cervical, and spine hyperextension at birth. We present here 41 cases of arthrogryposis (mainly Amyoplasia) with fetal cervical hyperextension. The outlook is surprisingly good if spinal cord trauma does not occur. Ultrasound late in pregnancy when arthrogryposis is recognized prenatally should determine whether cervical hyperextension has developed, so that appropriate preventive measures can be taken.

Planned caesarean section decreases the risk of adverse perinatal outcome due to both labour and delivery complications in the Term Breech Trial

OBJECTIVE

To determine if the decreased risk of adverse perinatal outcome, with a policy of planned caesarean, in the Term Breech Trial, was due to a reduction of problems of labour, problems of delivery or unrelated problems.

DESIGN

Secondary analysis of data from the Term Breech Trial, a randomised controlled trial of planned caesarean versus planned vaginal birth for the singleton fetus in frank or complete breech presentation at term.

SETTING

Women were recruited from 121 centres in 26 countries.

POPULATION

Women who were enrolled in the Term Breech Trial.

METHODS

Adverse perinatal outcome was classified as due to labour, due to delivery, due to neither labour nor delivery or unexplained by an experienced obstetrician who was masked to allocation group. The risk of an adverse outcome in each category was compared according to intention to treat and also by actual method of delivery.

MAIN OUTCOME MEASURES

Adverse perinatal outcome (excluding lethal congenital anomalies) that was due to labour, due to delivery, due to neither labour nor delivery or unexplained.

RESULTS

Planned caesarean was associated with a lower risk of adverse outcome due to both labour (RR 0.14, 95% CI 0.04-0.45, P < 0.001) and delivery (RR 0.37, 95% CI 0.16-0.87, P= 0.03), compared with planned vaginal birth. Prelabour caesarean and caesarean during early labour were associated with the lowest risk and vaginal birth was associated with the highest risk of adverse outcome due to both labour (0%, 0.4% and 2.2%, respectively) and delivery (0.2%, 0% and 3.1%, respectively).

CONCLUSIONS

Planned caesarean decreases the risk of adverse perinatal outcome due to both problems of labour and problems of delivery for the singleton fetus in breech presentation at term, compared with planned vaginal birth.

Breech vaginal delivery at or near term

Three percent to 4% of term fetuses will be breech at delivery. Evidence from randomized controlled trials has found a policy of planned cesarean section to be significantly better for the singleton fetus in breech presentation at term compared to a policy of planned vaginal birth. However, some women may wish to avoid cesarean section and for others, cesarean section may not be possible. We undertook this review to identify factors associated with higher and lower risk of adverse fetal or neonatal outcome at term during vaginal breech delivery. We searched MEDLINE from 1966 to 2002 using the search terms vaginal breech delivery and breech presentation and retrieved all relevant articles. We also reviewed personal references and reference lists of articles retrieved. Women who are older or who have a fetus that is either in footling presentation, has a hyperextended head or is estimated to weigh <2500 g or >4000 g may be at higher risk of adverse fetal outcome. Prolonged labor or not having an experienced clinician at vaginal breech birth may also increase the risk. Women with a fetus in breech presentation at term should be offered the option of delivery by planned cesarean section and should be informed that this will reduce their risk of adverse fetal or neonatal outcome. Practitioners should develop and maintain skills at vaginal breech delivery for those women not wishing or not able to be delivered by cesarean section.

The prognostic significance of hyperextension of the fetal head detected antenatally with ultrasound

OBJECTIVES

The purpose of this study was to evaluate the clinical significance of hyperextension of the fetal head detected by ultrasound prior to the onset of labour.

METHODS

Over a 10-year period, we retrospectively identified all fetuses who had hyperextension of the fetal head reported on antenatal ultrasound. Hyperextension referred to persistence of the cervical spine in extreme extension, with an extension angle of at least 150 degrees persisting for the duration of the scan. Follow-up information was obtained from Hospital medical records and obstetrical care providers.

RESULTS

Follow-up was obtained on 57 of the 65 fetuses (87.7%) identified over the study period. Ten of the 57 fetuses had normal structural fetal surveys and had sonographically identified resolution prior to delivery. All 10 patients delivered at term and had newborns with normal neonatal courses. Twenty-six of 57 fetuses had no sonographic findings other than persistent hyperextension, and 19 of these 26 fetuses (73%) had normal neonatal courses. Twenty-one of 57 fetuses (37%) had structural anomalies sonographically identified in addition to hyperextension of the fetal head. All 21 of these pregnancies ended in either termination or fetal or neonatal demize.

CONCLUSIONS

Although resolution of isolated hyperextension of the fetal head is associated with a normal neonatal outcome, persistent isolated hyperextension of the fetal head can be associated with either a normal or an abnormal neonatal outcome. Fetuses with hyperextended heads and antenatally diagnosed structural anomalies have dismal outcomes. The identification of a fetus with hyperextension of the fetal head should prompt a detailed search for structural abnormalities.

Controversies: the mature breech should be delivered by elective cesarean section

The fetal hazards of vaginal breech delivery have been recognised for centuries. In recent years the increased safety of Cesarean delivery has prompted a steady rise in its use for the delivery of the term breech fetus. In many maternity units more than 90% of breech babies are delivered in this way. In contrast some obstetricians argue that with appropriate selection criteria, safe, selective, vaginal breech delivery is possible. This argument is not supported by population studies, which indicate that perinatal mortality and morbidity rates associated with attempts at vaginal breech delivery are between 1-2%.

Management of breech presentation: the 1993 Israeli census

OBJECTIVES

To investigate current attitudes to management of labor and delivery in pregnancies complicated by breech presentation.

STUDY DESIGN

A questionnaire was sent to the directors of 23 units of maternal-fetal medicine, all members of the Israel Society of Perinatal Obstetricians. The survey included 69,072 deliveries in the year 1993. Current world literature on the topics included in the survey was also reviewed.

RESULTS

The overall response rate was 83% (19/23). The overall breech presentation rate was 3.4%, and overall caesarean section rate was 11.2%. In breech presentation, the caesarean section rate was 63.6%.

CONCLUSIONS

A rational approach allows vaginal breech delivery to be practiced in almost half of carefully selected cases. These results again emphasize the longstanding need for prospective randomized studies regarding the different aspects associated with the delivery of the fetus in breech presentation.

Undiagnosed breech

OBJECTIVES

To assess the proportion of breech presentations diagnosed in labour and to compare their outcomes with those diagnosed prior to the onset of labour.

DESIGN

Retrospective casenote review.

SETTING

Mill Road Maternity Hospital, a teaching hospital in central Liverpool.

SUBJECTS

Three hundred and five singleton breech presentations delivered in the hospital between January 1988 and July 1991; 226 cases prior to the onset of labour and 79 cases diagnosed for the first time in labour.

MAIN OUTCOME MEASURES

Rates of vaginal delivery and caesarean section, birthweight, short term morbidity as assessed by trauma, signs of cerebral irritation and admission to the newborn intensive care unit (NBICU), and Apgar scores.

RESULTS

Breech presentations diagnosed for the first time in labour were more likely to deliver vaginally than those assessed and allowed to go into labour (odds ratio 1:68 95% CI 1.0-3.0). This difference was not due to demographic variables or differences in birthweight. There was no short term morbidity attributable to vaginal breech delivery.

CONCLUSION

A significant number of breech presentations are not detected until labour despite rigorous antenatal surveillance. Our results show that undiagnosed breeches may not be important as they are more likely to deliver vaginally, with no excess morbidity or mortality, compared to diagnosed breeches in labour, carefully assessed for vaginal delivery. There are, therefore, no grounds for delivering all undiagnosed breeches by caesarean section.

Breech delivery and mental handicap

Recent studies with strict management protocols for selection of cases for trial of vaginal delivery for full-term breech presentations show no significant differences in outcome brought about by the birth route. This is in clear contrast to some of the older studies which indicated considerable risk for the vaginally born breech infant. Prospective follow-up studies and carefully matched controlled studies with sophisticated neurological evaluations indicate that breech infants, regardless of mode of delivery, will score slightly less favourably than infants born in vertex presentation. This difference seems to reflect prenatal factors rather than birth injuries.

Birth trauma and brain damage

Birth trauma is a rare primary cause of perinatal death, occurring at most only once in every 1000-2000 births. As a cause of brain damage and later handicap it is often difficult to dissociate injury at birth from the concomitant effects of asphyxia, growth retardation or preterm delivery. A continuum of reproductive casualty has been postulated, but for trauma is not proven. Among children with cerebral palsy and severe mental retardation trauma may be implicated in a few cases, possibly 1-2 of 1000 deliveries. Vaginal breech delivery has been related to a higher incidence of minimal brain damage syndromes and some of this damage probably has its origin in perinatal trauma. The pregnancies where there is particular risk of birth trauma include those where the infant is large for gestational age, has intrauterine growth retardation, is delivered preterm, is vaginally delivered in breech presentation or is from multiple gestation. Particular care must be given to diagnosis and preventive measures in these cases and competent handling is required if the disaster of brain damage caused by traumatic birth is to be minimized.

Balancing the risks of planned cesarean section and trial of vaginal delivery for the mature, selected, singleton breech presentation

The experience of mature, singleton, vaginal breech delivery over the last decade in our hospital is reviewed. This constitutes the largest series of breech delivery reported for over twelve years. Unlike all but two previous reports, we analyze our results by management policy; elective cesarean section, trial of vaginal breech delivery and cesarean section as soon as the diagnosis of breech delivery was made on labor ('expedite' cesarean operations). Six intrapartum or neonatal deaths occurred among 613 patients selected for trial of vaginal delivery--a rate of one per cent. There were none following 217 elective or 69 expedite cesarean sections. A detailed review of the literature over the last decade confirms that trial of vaginal delivery is more dangerous to the fetus and results in about one perinatal death of a normally formed infant in 200 deliveries. Apgar scores were slightly lower following trial of vaginal delivery and there were more irritable or injured babies in this group. The last intrapartum or neonatal death occurred in 1981. However, the elective cesarean section rate has increased from 14 to 33 per cent over this time period. Similarly the rate of failed trial of vaginal breech delivery has increased from 15 to 31 per cent. The proportion of failed trials was highest where the fetus was large but clinicians were poor at estimating fetal weight. Decision theory is used to examine the maternal utility of trial of vaginal breech delivery versus elective cesarean section when the intrapartum cesarean rate rises to these levels. It is shown that, from the point of view of maternal mortality and morbidity in the current pregnancy, trial of vaginal delivery maybe the more dangerous maternal option. Thus a low threshold for cesarean section in labor leads to greater fetal safety at the mother's expense. It is nevertheless concluded that maternal attitude and the long-term effects of a uterine scar should be considered in the final decision.

Modern strategy for the term breech delivery--a study with a 4-year follow-up of the infants

In a comprehensive 4-year follow-up study the long-term outcomes in 709 singleton term breech born infants were evaluated. The outcome has been related to different management protocols during two consecutive study periods. In the first period (A, 1971-1974) the rate of cesarean section was 16.1% and in the second period (B, 1974-1977) 37.1%. The neonatal mortality rate was the same in both study periods (0.3%). The incidence of long-term neurodevelopmental handicaps was in period A 5.3% and in period B 2.4% at 4 years of age. Sequelae among infants in period A were in most cases labor-related, i.e. footling, extended arms or difficulty in descent of the fetal head. An antero-posterior diameter of less than 12 cm at the brim was common in these cases. In both study periods there was an increased risk of neurodevelopmental handicaps for infants with hyperextension of the head in the breech position delivered by the vaginal route. In period B the incidence of neurodevelopmental sequelae at the 4-year follow-up did not differ from that found in a group of infants born vaginally in vertex presentation. The rates of visual and auditory disorders, behaviour problems, enuresis and late speech development were not increased in the breeches neither in period A nor in period B.