Breech delivery: evaluation of the method of delivery on perinatal results and maternal morbidity

The preterm breech delivery in Zaria, Northern Nigeria

The preterm breech occurred in 31.21% of singleton breech presentations in a prospective study at Ahmadu Bello University Teaching Hospital (ABUTH), Zaria, Nigeria. The uncorrected perinatal mortality of 670.5 per 1000 deliveries was 1.7 times that for term breech presentations. Failure to book for antenatal care (50.94%), admission of cases in the second stage of labor (21.84%) and intrauterine fetal death on admission (38.64%) were associated factors of the high perinatal mortality. The mortality was extremely high in the very low birthweight fetus (less than 1500 g) delivered vaginally. Moreover, the cesarean section rate was associated with a 2.4 times higher perinatal morbidity and mortality rates than vaginal delivery.

A multicentre randomised controlled trial comparing elective and selective caesarean section for the delivery of the preterm breech infant

OBJECTIVE

To determine the optimum mode of delivery for women in preterm breech labour at a gestational age of 26 to 32 weeks.

DESIGN

A multicentre randomised controlled trial.

SETTING

Twenty-six hospitals in England, UK.

PARTICIPANTS

Women with a singleton breech fetus in spontaneous preterm labour between 26 and 32 completed weeks of gestation, with no clear indication for a caesarean section or vaginal breech delivery.

INTERVENTION

Random allocation to either "intention to delivery vaginally' or "intention to deliver by caesarean section'.

MAIN OUTCOME MEASURES

Perinatal mortality, neonatal morbidity, maternal morbidity and gestation at delivery.

RESULTS

The trial was closed after 17 months because of low recruitment, by which time substantial numbers of women had been in the eligible gestation period. Thirteen women from six hospitals were recruited. One infant, randomised to and delivered vaginally, was stillborn. Three fetal presentations were cephalic at delivery despite a diagnosis of breech presentation at trial entry. No formal statistical analysis was performed due to the small numbers.

CONCLUSIONS

No conclusions about the optimum mode of delivery for women in preterm labour with a fetus presenting by the breech can be drawn from this trial. The low accrual rate was due to clinicians' reluctance to randomise eligible women, reflecting the circumstances and nature of the trial.

Route of delivery for the breech presentation: a conundrum

OBJECTIVE

Our purpose was to determine the feasibility of resolving the controversy regarding route of delivery for breech presentation in a randomized, prospective fashion.

STUDY DESIGN

The National Institute of Child Health and Human Development-sponsored Maternal-Fetal Medicine Units Network, which is composed of 11 perinatal centers, was surveyed to determine the feasibility of a randomized clinical trial of cesarean section versus trial of labor for breech presentation. A review of the literature was performed to determine the experience of other investigators with designing and conducting an adequate prospective, randomized trial.

RESULTS

Principal investigators and faculty from seven of 11 centers within the Maternal-Fetal Medicine Units Network agreed to participate adn felt that they could adequately recruit patients for a trial in very-low-birth-weight infants. This would provide approximately 200 very-low-birth-weight fetuses in a breech presentation per year. Sample size calculations indicated that 1700 infants would be required. Investigators also had strong reservations about performing a trial of vaginal breech delivery for other gestational ages. A review of the literature indicates that other authors have encountered difficulty in attempting randomized clinical trials of this nature.

CONCLUSIONS

The Maternal-Fetal Medicine Units Network with its pool of 60,000 deliveries per year agreed that a randomized, controlled delivery route of labor in the 24- to 28-week breech presentation was not feasible in a reasonable period of time. A randomized clinical trial of larger fetuses in a breech presentation was also considered extremely difficult. These findings are similar to those of other authors who have attempted or proposed randomized clinical trials to determine the safety of planned vaginal delivery of the breech presentation at various gestational ages.

Preterm breech delivery in a developing country

OBJECTIVES

To determine if cesarean section offers any advantage over vaginal delivery for a preterm breech fetus in a developing country.

METHODS

A retrospective analysis from hospital records was done at a tertiary care center in North India. Two hundred and twenty-four preterm breech deliveries (28-36 completed weeks) between January 1988 and December 1991 from a total of 13,149 deliveries at the hospital during this period formed the study group. Fetal death and lethal congenital malformations diagnosed antepartum were excluded. Intrapartum and neonatal morbidity and mortality in vaginal versus cesarean deliveries were the main outcome measures.

RESULTS

Although the combined intrapartum and neonatal mortality was significantly higher for vaginal delivery (35.9% vs. 17.7%), there was no significant difference when the data was correlated with birthweight or gestational age. The neonatal morbidity was also similar in both these groups. In women with a poor obstetric history, the neonatal survival was better in the cesarean group (93% vs. 43%; P = 0.0004).

CONCLUSION

Even with optimum neonatal care facilities, cesarean section does not offer any advantage over vaginal delivery for a preterm breech fetus in a developing country. The present study does not advocate the routine use of cesarean section for this group of fetuses. However, it is the preferred route of delivery for women with a poor obstetric history.

Breech delivery in very preterm and very low birthweight infants in The Netherlands

OBJECTIVE

To study the relation between various perinatal factors and the sequelae of very preterm birth, applying logistic regression analysis.

DESIGN

In a nationwide collaborative study in the Netherlands, perinatal and follow up data were collected on 899 liveborn singleton nonmalformed infants with gestational age less than 32 weeks or birthweight less than 1500 g born in 1983.

MAIN OUTCOME MEASURES

Neonatal mortality rate and total handicap rates (minor and major) in surviving children at two years and five years of age.

RESULTS

Comparing breech with vertex presentation, the odds ratio for neonatal mortality (adjusted for duration of pregnancy, birthweight, maternal hypertension and prolonged rupture of membranes) is 1.6 (P < 0.05). Comparing abdominal versus vaginal delivery, the odds ratio indicates equal risks. When breech and vertex presentation are analysed separately it appears that breech presenting infants have a significantly lower mortality risk when born by caesarean section compared with vaginal delivery. However, comparing abdominal versus vaginal delivery in breech presentation, the odds ratio for handicap at five years (0.9) is not significantly different from 1.

CONCLUSION

The data presented suggest a reduced neonatal mortality rate in breech presenting infants born by caesarean section but because of the observational design of the study the statistical analysis described only identifies a possible trend and cannot prove the issue.

Increased maternal morbidity after cesarean delivery before 28 weeks of gestation

To test the hypothesis that there is increased maternal morbidity associated with cesarean section at very early gestational ages compared to cesarean section at term, a case-control study was performed. Eighty consecutive cases of cesarean section before 28 weeks of gestation were chronologically matched to 80 controls with cesareans at term. Compared to term controls, preterm cases were more frequently complicated by postpartum endomyometritis (32% vs. 9%, P < 0.001) and blood transfusion (14% vs. 1%, P < 0.01), resulting in a significantly longer postpartum stay and longer duration of antibiotic use. One or more major complications occurred in 45% of preterm cases versus 14% of controls (P < 0.001); two major complications occurred in 11% of cases versus 1% of controls (P < 0.05). Some, but not all, of the higher risk for postpartum complications was attributable to pre-existing differences in risk factors for infection and hemorrhage between the two groups. We conclude that cesarean section before 28 weeks of gestation is associated with a high risk of postoperative complications and that patients should be counseled accordingly.

Mode of delivery and neonatal death in 17,587 infants presenting by the breech

OBJECTIVE

To study the effects of caesarean section on neonatal mortality in infants presenting by the breech.

DESIGN

Population-based non-experimental comparison of infants presenting by the breech born vaginally with those born by caesarean section. Neonatal mortality rates were calculated for 250 g birthweight intervals. Weight-specific relative risks (RRs) were further adjusted for birthweight in 50 g categories.

SETTING

New York City, 1978-1983. Data came from the Department of Health's computerized vital records on livebirths and infant deaths.

SUBJECTS

17,587 singleton breech livebirths greater than or equal to 500 g birthweight, with congenital anomaly deaths excluded. 6178 were born vaginally and 11409 were born by caesarean section.

MAIN OUTCOME MEASURES

Birthweight-specific and birthweight-adjusted neonatal mortality.

RESULTS

At birthweights of 501 to 1750 g, the risk of neonatal death for breech infants born vaginally was significantly higher than the risk for those born by caesarean section (weight-adjusted RR = 1.7). For breech infants with birthweights over 3000 g, the weight-adjusted risk was 5.6 times greater for a vaginal birth compared with caesarean section. The addition of 16 additional control variables in multiple logistic regression analyses did not change these RRs.

CONCLUSION

Population-based studies indicate that an increase in the caesarean section rate among breech singletons may be associated with increased neonatal survival, but a large multicentre randomized trial of management of breech presentation would answer the question much more definitively.

Safety of term vaginal breech delivery

Of 247 women who were pregnant of one healthy child in breech presentation at term, 13 (5.3%) were delivered by a primary cesarean section. The other 234 (94.7%) were allowed to attempt vaginal birth. In these women, the only factor to determine the possibility of a vaginal delivery was normal progression of labor during the first stage, without secondary arrest or signs of fetal distress. 109 Women (44.1%) were delivered spontaneously according to Bracht, 87 (35.2%) had an assisted breech delivery, and 38 (15.4%) underwent a secondary cesarean section. There were two perinatal deaths (0.8%). One of them was directly related to the trial of labor. Two children with a birth trauma had an uneventful recovery. The 1 min Apgar score in all breech delivery groups was more often lower than in a control group of children, who were born spontaneously at term in vertex presentation. However, the 5 min Apgar score and the mean umbilical artery pH were within normal limits in all groups. The secondary cesarean section rate was inversely related to vaginal parity of the mother, and directly related to the newborns' birth weight. There was no relation between the secondary cesarean section rate and the type of breech presentation. It is concluded, that a trial of labor in carefully selected patients with a child in breech presentation at term is a safe procedure, that can be successfully completed in almost 80% of cases. In retrospect, low vaginal parity and high birth weight of the newborn have a negative influence on normal progression of labor.

How obstetricians manage the problem of preterm delivery with special reference to the preterm breech

A questionnaire regarding the route of birth for the preterm fetus with particular reference to the management of the preterm breech was sent to 180 consultants in England and Wales. Only 23% of respondents use electronic fetal monitoring below 26 weeks gestation and only 12% use caesarean section routinely for fetal indications at less than 26 weeks. Only 12% will use caesarean section for the preterm fetus presenting by the vertex in uncomplicated labour. Only 35% of all respondents consider that there is sufficient evidence to support the use of caesarean section for the uncomplicated preterm breech, but 76% will actually use caesarean section for this indication. Overall 71% reported that they are affected by medicolegal considerations in their management of the preterm breech. Overall, 83% said that they might change their practice regarding the mode of delivery of the preterm breech in the light of the findings of a randomized prospective controlled trial.

Breech vaginal delivery after one cesarean section: a retrospective study

This retrospective study evaluates the prospects of allowing a vaginal breech to follow a previous lower segment cesarean section by examining data from Farwania Hospital, Kuwait where 33 (38.4%) of 86 patients with a previous cesarean section with fetuses in breech presentation were given a chance for vaginal delivery. The remaining 53 patients were delivered by lower segment cesarean section. Out of 53 patients, 34 patients were sectioned because of the presence of uterine scar. The other 19 patients were sectioned because of the additional presence of other obstetric complications such as diabetes, pre-eclamptic toxemia or large fetus. This group of patients was excluded from comparison.

Reasons for declining participation in a prospective randomized trial to determine the optimum mode of delivery of the preterm breech

Increasing numbers of preterm breech infants are being delivered by cesarean section, which confers no proven advantage to the infant and subjects the mother to increased risk. In order to assess the feasibility of performing a randomized controlled trial to compare elective with selective cesarean delivery for the preterm breech infant, consultants in 36 hospitals were asked if they would be willing to participate. In 25 hospitals all consultants agreed to participate, whereas in 11 universal support was not obtained. The reasons given for nonparticipation included the potentially time-consuming nature of the consent procedure, which it was proposed should be undertaken with all women during the antenatal period, concern that a large proportion of non-English speak women would not be able to give truly informed consent, anxiety about the seniority, availability, and requisite skill of the personnel delivering the preterm breech, doubts about the details of the protocol, medicolegal considerations, and disagreement about the desirability of the trial among the consultant members of a department. If prospective evaluation of clinical practice is to be carried out in the future the staffing levels of obstetric departments must taken into account the additional work load that this entails.

Delivery of the low birthweight and the very low birthweight breech: cesarean section or vaginal delivery?

We studied neonatal survival rates, APGAR scores, and length of hospital stay in 199 singleton breeches weighing 1000-2500 grams at birth. We found that in the birthweight range of 1000-1750 grams, breeches who were delivered by cesarean section had a significantly higher survival rate (74%) than those who were delivered vaginally (36%, p less than 0.01), however, in the birthweight range of 1751-2500 grams, there was no significant difference in the survival rates between breeches delivered abdominally and those delivered vaginally. The 1-minute and the 5-minute APGAR scores and the length of the hospital stay were not significantly different between the abdominal and the vaginal delivery groups in either birthweight range. The data indicate that the very low birthweight breech (less than or equal to 1750 grams) may benefit from a prophylactic cesarean section.

Apgar scores and umbilical cord arterial pH in the breech neonate

Apgar scores and umbilical cord arterial pH measurements of 449 singleton breech deliveries are compared retrospectively to those of 1425 singleton vertex neonates. In the vaginal deliveries the Apgar scores and umbilical arterial pH were higher for the vertex neonates. There were no differences in either Apgar scores or umbilical arterial pH between the breech and vertex neonates delivered by cesarean section. Whereas Apgar scores in the less than 1000 g and greater than or equal to 2500 g weight groups were lower in the breech neonates delivered vaginally compared to cesarean section, umbilical arterial pH measurements were similar. The data suggest that liberal use of cesarean section may improve the Apgar scores but will probably not appreciably improve the acid-base status of the breech neonate.

Outcome of singleton infants delivered vaginally or by caesarean section at 23 to 28 weeks' gestation

The survival and impairment rates of 276 inborn singleton infants of 23-28 weeks' gestation were reported according to route of delivery and mode of presentation. The Caesarean section rate was 29% overall, ranging from 13% at 25 weeks to 46% at 28 weeks. In the vertex group, no significant difference in survival or impairment rate was found between Caesarean and vaginal births. In the non-vertex group, Caesarean births had a similar survival rate but a significantly lower impairment rate compared to vaginal births. For Caesarean births, no significant difference in survival or impairment rate was found between vertex and non-vertex groups. In contrast, for vaginal births, the mode of presentation was important: the non-vertex group had a significantly lower survival rate and higher impairment rate compared to the vertex group. We found no evidence to support the use of Caesarean section in extremely preterm infants with vertex presentation, except for recognized maternal or fetal indications. The findings in the non-vertex group indicated that there is a definite need for a randomized clinical trial to investigate the possible benefits of Caesarean section in extremely preterm infants with non-vertex presentation.

Breech delivery: why the dilemma?

A critical review of selected studies of breech delivery is presented with special attention to the statistical analysis of outcome for low birth weight and term breech delivery. Analysis of the data fails to support the routine use of cesarean birth for all cases of breech delivery except for those with hyperextension of the head. The implication of these findings is discussed.

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.

Delivery type and neonatal mortality among 10,749 breeches

Data on 10,749 breech presentations were analyzed for the effect of delivery type on neonatal mortality. Most of the data are from developing countries, and most of the hospitals have higher mortality than is found in Europe or the United States. The simultaneous effect of type of hospital where the delivery occurred, type of breech, birthweight, and parity were examined. The benefit of cesarean delivery was greater for nulliparae than multiparae, greater for footlings than for frank or complete breeches, and greater for larger babies than smaller ones. This last finding probably reflects the quality of neonatal care in developing country hospitals rather than the value of cesarean section. Maternal mortality and morbidity was higher among women delivered abdominally than among those delivered vaginally.

Has use of cesarean section reduced the risks of delivery in the preterm breech presentation?

The effect of cesarean section on the condition at birth in cases of preterm breech presentation was studied in consecutively delivered infants in two time periods. Delivery was rarely (8%) by cesarean section in 1961 to 1974 and usually (89%) by cesarean section in 1978 to 1984. The increased cesarean rate did not reduce the incidence of severe depression, which was double that in control cases with cephalic presentations in both periods. Breech births did not have a higher mortality rate than cephalic births in either period; birth trauma and encephalopathy were similar in both periods. Cesarean section was therefore not found to reduce either the incidence of depression at birth or the mortality. However, head entrapment was responsible for the deaths of seven of 55 live-born infants delivered vaginally at 25 to 28 weeks' gestation, all weighing less than 1000 gm. Although cesarean section is at present performed least often among these extremely premature infants, it is in these cases that it may prove most beneficial.

Outcome for the very low birth-weight (500-1,499g) singleton breech: benefit of caesarean section

Between January 1, 1977 and March 31, 1982, 84 of 131 (64.1%) consecutive liveborn very low birth-weight (VLBW) singletons delivered after breech presentation were discharged home alive. Of babies delivered by Caesarean section 40 of 47 (85.1%) survived, versus 44 of 84 (52.4%) delivered vaginally (X2 = 12.6, p less than 0.0005). When differences in birthweight and antenatal steroid therapy were adjusted by multiple regression analysis, after excluding a lethally malformed baby who was diagnosed antenatally and babies who were not treated aggressively because they were thought to be too immature (n = 19), those delivered by Caesarean section were still more likely to survive (p = 0.038). In survivors completely assessed at 2 years of corrected age, there was a statistically significant association between Caesarean section and reduced handicap (p = 0.019). For the VLBW singleton breech, there is good evidence that delivery by Caesarean section is beneficial.

Mortality in relation to method of delivery in breech infants

To study the relation of method of delivery to perinatal mortality, we examined information from the deliveries of 1593 breech infants weighing 1000 g or more born in 1976 and 1977. In none of the birthweight groups 1000 g or more was neonatal mortality significantly different between infants delivered vaginally compared with those delivered by cesarean section, although the number of deaths was small. In all the birthweight groups, perinatal mortality was higher in breeches delivered vaginally, but the differences were because all of the infants who died before labor were delivered vaginally. Total mortality (intrapartum plus neonatal deaths) in infants who survived to labor was not significantly different in breech infants delivered by one or the other method at any birthweight. These data suggest that routine cesarean delivery for infants 1000 g or more who are in the breech presentation may not be justified from the standpoint of mortality.

Cesarean section versus vaginal delivery for the breech fetus weighing less than 1,500 grams

Although previous studies have suggested that the breech infant weighing less than 1,500 gm benefits from cesarean section, the published results have not demonstrated statistically significant differences. We have evaluated pediatric outcome data for 240 breech infants and 525 vertex infants who weighed less than 1,500 gm, to determine whether route of delivery affects infant morbidity and mortality. Twenty-nine percent of these very small breech infants who were delivered by cesarean section died, as compared to 58% of breech infants of similar weight who were delivered vaginally (p less than 0.001). Comparable significant differences were found for the infants delivered at a university hospital as well as for those delivered at a group of nonuniversity hospitals. Apgar scores and the incidence and severity of intraventricular hemorrhage were not different for the cesarean section and vaginally delivered breech infants. Furthermore, the survival rate of the breech infants delivered by cesarean section equaled that of the vertex infants delivered either by cesarean section or vaginally.

Identifying the sources of the recent decline in perinatal mortality rates in California

The perinatal mortality rate in California decreased rapidly in the 1970s; neonatal mortality fell about twice as fast as fetal mortality. Decreases in birth-weight-specific mortality accounted for 81 per cent of the decline in the perinatal rate, with only 19 per cent due to improvements in birth weight. No improvement was observed in the birth-weight distribution for blacks. The decrease in mortality rates was significantly faster for cesarean deliveries than for vaginal births. By 1977, all birth-weight-specific fetal mortality rates for cesarean sections were equal to those for vaginal deliveries or lower. For infants weighing less than 2000 g, perinatal mortality rates were also significantly lower for infants born by cesarean section than for infants delivered vaginally. These results suggest that much of the recent decrease in perinatal mortality rates can be attributed to the advent of neonatal intensive care and the increased rate of cesarean section.