Breech presentation occurs in 3-4% of all deliveries. The occurrence of breech presentation decreases with advancing gestational age. Breech presentation occurs in 25% of births that occur before 28 weeks?gestation, in 7% of births that occur at 32 weeks, and 1-3% of births that occur at term.
Predisposing factors for breech presentation include prematurity, uterine abnormalities (eg, malformations, fibroids), fetal abnormalities (eg, CNS malformations, neck masses, aneuploidy), and multiple gestations. Abnormalities are observed in 17% of preterm deliveries that have breech presentation and in 9% of term gestations with breech presentation.
Perinatal mortality is increased 2- to 4-fold with breech presentation, regardless of the mode of delivery. Deaths most often are associated with malformations, prematurity, and intrauterine fetal demise.
Types of breeches
|VAGINAL BREECH DELIVERY||¡@|
Vaginal breech deliveries previously were the norm until 1959 when Wright proposed that all breech presentations should be delivered abdominally to reduce perinatal morbidity and mortality.
Vaginal breech delivery
Three types of vaginal breech deliveries are described, as follows:
Spontaneous breech delivery: No traction or manipulation of the infant is employed. This occurs predominantly in very preterm deliveries.
Assisted breech delivery: This is the most common type of vaginal breech delivery. The infant is allowed to spontaneously deliver up to the umbilicus, and then maneuvers are initiated to assist in the delivery of the remainder of the body, arms, and head.
Total breech extraction: The fetal feet are grasped, and the entire fetus is extracted. It should be used only for the noncephalic second twin. It should not be used for singleton fetuses because the cervix may not be adequately dilated to allow passage of the fetal head. If the feet prolapse through the vagina, expectantly manage as long as the fetal heart rate is stable to allow the cervix to completely dilate around the breech (see Picture 1). Total breech extraction for the singleton breech is associated with a 25% rate of birth injuries and a mortality rate of approximately 10%.
Technique and tips for assisted vaginal breech delivery
Leaving the fetal membranes intact as long as possible to act as a dilating wedge and to prevent overt cord prolapse is advisable.
Oxytocin induction and augmentation are controversial. Many studies use oxytocin for induction and augmentation for dysfunctional labor, especially for hypotonic uterine dysfunction. Other studies warn that nonphysiologic forceful contractions could result in an incompletely dilated cervix and an entrapped head.
An anesthesiologist and pediatrician should be present for all vaginal breech deliveries. Pediatricians are needed because of the higher incidence of neonatal depression and the increased risk for unrecognized fetal anomalies. General anesthesia may be needed if intrapartum complications develop.
Perform episiotomy when “crowning.?This is advocated by many authors for all breech deliveries, even in multiparas, to prevent soft tissue dystocia (see Picture 2, Picture 3).
The Pinard maneuver may be needed with a frank breech to facilitate delivery of the legs, only after the fetal umbilicus has been reached. Pressure is exerted against the inner aspect of the knee. Flexion of the knee follows, and the lower leg is swept laterally and out of the vagina. No traction should be exerted on the infant until the fetal umbilicus is past the perineum, after which time maternal expulsive efforts should be used along with gentle downward and outward traction of the infant until the scapula and axilla are visible (see Picture 4).
Use a dry towel to wrap around the hips, not the abdomen, to help with gentle traction of the infant (see Picture 5). The assistant should exert transfundal pressure from above to keep the head flexed.
Once the scapula is visible, rotate the infant 90?and gently sweep the anterior arm out of vagina by pressing on the inner aspect of the elbow (see Picture 6, Picture 7). Rotate the infant 180?in the reverse direction, and sweep the other arm out of the vagina. Once the arms are delivered, rotate the infant back 90?so that the chin is posterior (see Picture 8).
The head should be maintained in a flexed position during delivery to allow passage of the smallest diameter of the fetal head. The flexed position can be accomplished by using the Mauriceau-Smellie-Veit maneuver (fingers placed over maxilla, see Picture 9) or with Piper forceps while the assistant applies suprapubic pressure. During the Mauriceau-Smellie-Veit maneuver, the operator applies pressure over the fetal maxillary prominences. Piper forceps are specialized forceps with pelvic, not cephalic, application, which maintains the head in a flexed position (see Picture 10).
The forceps are applied while the assistant supports the fetal body in a horizontal plane. Many early studies recommended routine use of Piper forceps to protect the head and to minimize traction on the fetal neck.
During delivery of the head, avoid elevation of the body, which might result in hyperextension of the cervical spine and potential neurologic injury (see Picture 12, Picture 13).
The Bracht maneuver is a variant approach to the assisted vaginal breech delivery. This procedure, first described in 1938, attempts to simulate the cardinal movements observed in spontaneous vaginal breech deliveries. The breech is allowed to spontaneously deliver to the level of the umbilicus. After spontaneous rotation of the infant to a spine-anterior position, the operator gently holds the body and legs upward against the maternal symphysis. With the force of uterine contractions and moderate suprapubic pressure by an assistant, the fetal arms are delivered without traction, and the head, which has been hyperextended at the neck, follows shortly thereafter.
While the Bracht maneuver initially was evaluated in Europe, it was never popularized in the United States, and it is mentioned predominantly for historical interest.
Lower Apgar scores, especially at 1 minute, are a risk. Consider obtaining an umbilical cord pH on all vaginal breech deliveries to document whether neonatal depression is due to perinatal acidosis and asphyxia.
An entrapped head may result from an incompletely dilated cervix or from a fetal head that lacked time to mold to the maternal pelvis. This occurs in 0-8.5% of vaginal breech deliveries. This figure is higher with preterm fetuses (prior to 32 wk), when the head is larger than the body and may become trapped in an incompletely dilated cervix. Dührssen incisions, ie, 2 or 3 cervical incisions made to facilitate delivery of the head, may be necessary for cervical entrapment. However, extension can occur into the lower segment of the uterus, and the operator needs to be equipped to deal with this complication. The Zavanelli maneuver is replacement of the fetus into the abdominal cavity and performing a cesarean delivery. This too has been described, with varying outcomes including fetal injury and even fetal death.
Nuchal arms are present in 0-5% of vaginal breech deliveries. Nuchal arms are present in 9% of breech extractions. Nuchal arms result in neonatal trauma in 25% of cases. Risks may be reduced by avoiding rapid extraction of the infant during delivery of the body. To treat nuchal arms, rotate the infant so that the fetal face rotates toward the symphysis pubis, effectively reducing the tension holding the arm around the back of the fetal head.
Cervical spine injury is observed predominantly with a hyperextended head. Ballas reported 20 cases of hyperextended necks on x-ray, defined as an angle of extension greater than 90?(“star-gazing?. Of the 11 fetuses who were delivered vaginally, 8 (73%) sustained complete cervical lesions of the spinal cord, defined as either transection or nonfunction.
Cord prolapse occurs in 7.5% of all breeches. Of cord prolapses, 0-2% occur with frank breech, 5-10% occur with complete breech, and 10-25% occur with footling breech. Cord prolapse occurs twice as often in multiparas (6%) than in primigravidas (3%). Cord prolapse may not result in severe fetal heart rate decelerations because of lack of presenting parts compressing the umbilical cord (ie, that which predisposes also protects).
Approximately 50% of those with breech presentation are candidates for vaginal delivery. Of these candidates, 60-82% successfully deliver vaginally.
Gestational age younger than 26 weeks, not mode of delivery, is the greatest risk factor for the neonate. Vaginal delivery can be considered, but open and honest discussion of risks from prematurity and lack of data regarding the ideal mode of delivery should be reviewed with the parents.
If gestational age is 26-32 weeks, consider caesarean delivery based on retrospective reports. After 32 weeks?gestational age, consider vaginal breech delivery after a discussion of risks and benefits with the parents. If estimated fetal weight (EFW) is 4000-4500 g, some recommend caesarean delivery because of concern for entrapment of the unmolded head in the maternal pelvis, although limited data exist to support this approach.
A frank breech presentation is preferred for trial of vaginal delivery. Complete breeches and footling breeches still are candidates as long as the breech infant is well applied to the cervix.
The infant should show no hyperextension of the neck on ultrasound evaluation (see Picture 13). Flexed or military position is acceptable.
Prior cesarean delivery: A retrospective report from Israel on 71 women with one prior low-transverse cesarean delivery who delivered a breech fetus found that 24 women had an elective repeat cesarean delivery, and 47 women had a trial of labor. Of the 47 women, 37 (78.7%) trials of labor resulted in vaginal delivery. Ten out of 24 women with cesarean delivery had febrile morbidity, and 2 women had uterine dehiscence. In the group of vaginal deliveries, 2 infants had nuchal arms (1 with a transient brachial plexus injury) and 1 woman required a hysterectomy for hemorrhage due to a uterine dehiscence recognized after vaginal delivery. Vaginal breech delivery after one prior cesarean delivery is probably safe; however, more studies are needed.
Primigravida versus multiparous
It commonly is believed that primigravidas should be delivered by cesarean delivery, although no data (prospective or retrospective) exist to support this view. The only documented risk related to parity is cord prolapse, which is 2-fold higher in parous women than in primigravidas.
Historically, pelvimetry was believed to be useful to quantitatively assess the inlet and midpelvis. CT pelvimetry, which uses less fetal radiation exposure than conventional x-ray pelvimetry, has been advocated by some investigators. Although it was popularized approximately 10 years ago, it is rarely used today.
Recommended criteria include that the inlet has a transverse diameter larger than 11.5 cm and an anteroposterior diameter larger than 10.5 cm and that the midpelvis has a transverse diameter (between ischial spines) larger than 10 cm and an anteroposterior diameter larger than 11.5 cm.
Table 1. Zatuchni-Andros Breech Scoring
|¡@||Add 0 Points||Add 1 Point||Add 2 Points|
|Gestational age (wk)||39+||38||<37|
If the score is 0-4, cesarean delivery is recommended.
If the operator is not experienced or comfortable with vaginal breech deliveries, cesarean delivery may be the best choice.
With the dwindling numbers of experienced obstetricians who perform vaginal breech deliveries, it is uncertain who will teach future generations about this technique. It is feared that vaginal breech deliveries will become a lost art.
The rate of cesarean delivery for breech presentation in the United States was 14% in 1970 and 86% in 1986. It currently is 90-95%. Breeches account for 10-15% of all cesarean deliveries. Green compared perinatal outcome for term breeches prior to 1975 (595 infants, cesarean delivery rate for breeches 22%) to 1978-1979 (164 infants, cesarean delivery rate 94%). Despite the increase in rates of cesarean delivery, no significant differences existed in rates of asphyxia, birth injury, or perinatal deaths.
Maneuvers for delivery are similar for vaginal breech delivery (eg, Pinard maneuver, ie, wrapping the hips with a towel for traction, head flexion during traction, rotation and sweeping out of arms; Mauriceau-Smellie-Veit maneuver).
An entrapped head still can occur during cesarean delivery if the uterus contracts down after delivery of the body, even with an adequate-appearing lower uterine segment. Entrapped heads occur more commonly with preterm breeches, especially with a low transverse uterine incision. Many authors advocate low vertical uterine incisions for the preterm breech. Low vertical incisions usually require extension into the corpus, resulting in cesarean delivery with all future deliveries.
If the point of cesarean delivery is to avoid trauma to the fragile preterm fetus, the cesarean delivery should be performed in the least traumatic fashion, which often is with a vertical uterine incision. If a low transverse incision is performed, try to keep membranes intact as long as possible and move quickly once the breech is extracted to deliver the head before the uterus begins to contract down. Extending the transverse incision vertically upwards ("T" incision) is possible if any difficulty occurs with delivery of the fetal head. Alternatively, the transverse incision can be extended laterally while curving upward, avoiding trauma to the uterine arteries. If the patient is in the operating room and anesthesia support is available, a short-acting dose of nitroglycerin may relax the uterus and cervix and simplify delivery.
Only 3 randomized studies have evaluated mode of delivery of the term breech. All other studies were nonrandomized or retrospective. Nonrandomized studies are subject to selection bias.
Collea et al randomized 208 laboring women with frank breech presentations at term to either attempted vaginal delivery after x-ray pelvimetry versus elective cesarean delivery. Oxytocin was allowed for dysfunctional labor. Of the 60 women with adequate pelves, 49 delivered vaginally. Two infants had transient brachial plexus injuries. Women randomized to elective cesarean delivery had higher postpartum morbidity rates (49.3% vs 6.7%).
Gimovsky et al randomized 105 laboring women with term nonfrank breech presentations to a trial of labor versus elective cesarean delivery. In this group of women, 47 had complete presentations, 16 had incomplete presentations (hips flexed, 1 knee extended/1 knee flexed), 32 had double-footling presentations, and 10 had single-footling presentations. Oxytocin was allowed for dysfunctional labor. Of the trial labor group, 44% had successful vaginal delivery. Most cesarean deliveries in the trial labor group were performed for inadequate x-ray pelvimetry. No difference in neonatal morbidity existed between infants delivered vaginally versus infants delivered by cesarean delivery, although a higher maternal morbidity rate occurred in the cesarean delivery group.
In 1993, Cheng and Hannah reviewed 24 studies comparing vaginal versus cesarean delivery for the term breech fetus.
Table 2. Vaginal Versus Cesarean Delivery for the Term Breech Fetus
|¡@||Odds Ratio (OR)||95% Confidence Interval (CI)|
|Corrected perinatal mortality||3.86||2.22-6.69|
|Low 5-minute Apgar score (<7)||1.95||1.45-2.61|
|Birth trauma (0.3-6%)||3.96||2.76-5.67|
|Maternal morbidity and mortality||0.61||0.47-0.80|
In 2000, Hannah and colleagues completed a multicenter randomized clinical trial involving 2088 term fetuses in frank or complete breech presentations at 121 institutions in 26 countries. The individuals were randomized into a planned cesarean delivery group or a planned vaginal birth group. Exclusion criteria were estimated fetal weight heavier than 4000 g, hyperextension of the fetal head, lethal fetal anomaly or anomaly that may result in difficulty with delivery, or contraindication to labor or vaginal delivery (eg, placenta previa).
Women randomized to a cesarean delivery were scheduled to be delivered after 38 weeks?gestation, unless the fetus had converted to cephalic presentation. Women randomized to a vaginal delivery were treated expectantly until labor ensued. Electronic fetal monitoring was either continuous or intermittent. Inductions allowed for standard obstetrical indications, such as postterm gestations. Augmentation with oxytocin was allowed in the absence of apparent fetopelvic disproportion. Epidural analgesia was permitted.
Adequate labor was defined as a cervical dilatation rate of 0.5 cm/h in the active phase of labor and descent of breech to the pelvic floor within 2 hours of achieving full dilatation. Vaginal delivery was spontaneous or assisted and was attended by an experienced obstetrician as determined by the department head. Cesarean deliveries were performed for inadequate progress of labor, nonreassuring fetal heart rate, or conversion to footling breech. Results were analyzed by intent-to-treat (ie, subjects were analyzed by randomization group, not by ultimate mode of delivery).
Of 1041 women in the cesarean delivery group, 941 (90.4%) underwent cesarean delivery. Vaginal delivery occurred for those with immanent vaginal birth (59), for those with a patient request (29), and for those with cephalic presentation (12). No reason was given for 5 of the vaginal deliveries who were first intended to be cesarean deliveries. Of 1042 women in the planned vaginal group, 591 had vaginal deliveries. Cesarean delivery was performed for those with fetopelvic disproportion or failure to progress in labor (226), nonreassuring fetal heart rate tracing (129), a footling breech (69), a patient request (61), obstetrical or medical indications (45), or cord prolapse (12). No reason was given for 8 of the cesarean deliveries who were first intended to be vaginal deliveries.
Combined measurement of perinatal mortality, neonatal mortality, or serious neonatal morbidity was significantly lower in the planned cesarean group versus the planned vaginal group (5% vs 1.6%, P <0.0001). Six of 16 neonatal deaths were associated with difficult vaginal deliveries, and 4 deaths were associated with fetal heart rate abnormalities. The reduction in risk in the cesarean group was even greater in those participating countries with overall low perinatal mortality rates as reported by the World Health Organization. The difference in perinatal outcome held after controlling for the experience level of the obstetrician. No significant difference was present between the 2 groups in maternal mortality or serious maternal morbidity within the first 6 weeks of delivery (3.9% vs 3.2%, P = 0.35).
Only one prospective randomized study has been performed on the preterm breech, a randomized clinical trial of 38 women with preterm labor (28-36 wk) with breech presentations. Of these women, 20 were randomized to attempted vaginal delivery and 18 were randomized to immediate cesarean delivery. Of the vaginal group, 25% of patients underwent cesarean delivery for nonreassuring fetal heart rate tracing. Five neonatal deaths occurred in the vaginal group, and 1 neonatal death occurred in the cesarean delivery group. Two infants died from fetal anomalies, 3 infants died from respiratory distress, and 1 infant died from sepsis.
No nonanomalous infants who died were acidotic at delivery or had birth trauma. No significant differences in Apgar scores existed, although a trend toward lower Apgar scores existed in the vaginal group. The small number of enrolled subjects made reaching any definitive conclusions regarding the safety of vaginal breech delivery for the preterm breech difficult.
Retrospective analyses showed higher mortality in vaginal breech infants weighing 750-1500 g (26-32 wk), but less certain benefit was shown with cesarean delivery if the fetal weight was heavier than 1500 g (approximately 32 wk). This small subgroup (26-32 wk) may benefit from cesarean delivery, although this recommendation is based on retrospective data that is likely flawed by selection bias.
The Maternal-Fetal Medicine Units Network of the National Institute of Child Health and Human Development considered a multicenter randomized clinical trial of attempted vaginal delivery versus elective cesarean delivery for 24- to 28-week breech fetuses; however, it was not initiated because of anticipated difficulty with recruitment, inadequate numbers to show statistically significant differences, and medical-legal concerns. This study is not likely to be performed.
|EXTERNAL CEPHALIC VERSION||¡@|
External cephalic version (ECV) is the transabdominal manual manipulation of the fetus into a cephalic presentation.
Initially popular in the 1960s and 1970s, ECV virtually disappeared after reports of fetal deaths following the procedure. Reintroduced to the United States in the 1980s, it became increasingly popular in the 1990s.
Improved outcome may be related to the use of nonstress tests both before and after ECV, improved selection of low-risk fetuses, and Rh-immune globulin to prevent isoimmunization.
Prepare for the possibility of cesarean delivery. Type and screen the blood of the patient, and obtain a consultation with an anesthesiologist. The night before the procedure, the patient should have nothing by mouth after midnight. Perform an ultrasound to confirm breech, to check growth and amniotic fluid volume, and to rule out anomalies associated with breech.
Perform a nonstress test (biophysical profile as back-up) prior to ECV to confirm fetal well-being.
Perform ECV in or near a delivery suite in the unlikely event of fetal compromise during or following the procedure.
ECV can be performed with 1 or 2 operators. An assistant may help turn the fetus or elevate the breech out of the pelvis or monitor the ultrasound position of the baby.
ECV is accomplished by judicious manipulation of the fetal head toward the pelvis while the breech is brought up toward the fundus. Attempt a forward roll first and a backward roll if the initial attempt is unsuccessful. No consensus exists on how many ECV attempts are appropriate at one time.
Following an ECV attempt, whether successful or not, repeat the nonstress test (biophysical profile if needed) prior to discharge. Also, administer Rh-immune globulin to women who are Rh negative. Be prepared for an unsuccessful ECV. Do not be ashamed if the ECV is unsuccessful. Some physicians induce labors following successful ECV, while others discharge and await spontaneous labor.
Success rates vary widely but range from 35-86% (average 58%). Improved success rates occur with multiparity, earlier gestational age, frank breech, transverse lie, and in African American patients. Disagreement over influence of maternal weight, placental position, and amniotic fluid volume exist with regards to success rates.
Newman developed a Bishop-like score to predict ECV success.
Table 3. Scores to Predict External Cephalic Version Success
|¡@||Add 0 Points||Add 1 Point||Add 2 Points|
|Dilatation||>3 cm||1-2 cm||0 cm|
The success rate was 0% with a score of less than 2 and 100% with a score of greater than 9. Significant overlap in scores between the successful and unsuccessful ECVs render the scoring system clinically less useful.
Zhang reviewed 25 studies of ECV in the United States, Europe, Africa, and Israel. The average success rate in the United States was 65%. Of ECVs, 2.5% reverted to breech (other estimates range from 3-5%) and 2% spontaneously verted to cephalic prior to labor (other estimates range from 12-26%). Spontaneous version rates depend on the gestational age when the breech is discovered, with the earlier breeches more likely to vert spontaneously.
ECV attempts to decrease the cesarean delivery rate for breech by 50% (83.2% to 36.7%). Because breech presentations complicate only 3-5% of all deliveries, decreasing the cesarean delivery rate for breeches by 50% has minimal impact on the overall cesarean delivery rate.
Hofmeyr from the Cochrane Database reviewed 6 randomized clinical trials of ECV versus no ECV at term. ECV was associated with significant reduction in breech presentations (relative risk [RR] 0.42, 95% CI 0.35-0.5) and reduction in cesarean delivery for breech (RR 0.52, 95% CI 0.39-0.71).
While most studies of ECV have taken place in university hospitals, ECV also has been shown to be effective in the private practice setting (Cook, 1993). Of 65 breeches at term, 60 were offered ECV. Successful ECV occurred in 32 of 60 (53%) patients, with vaginal delivery in 23 of 32 patients (72%) of successful ECVs. Of the 10 candidates for vaginal breech delivery, 8 (80%) had successful vaginal delivery. The overall vaginal delivery rate was 48% (31 of 65 patients), with no significant morbidity.
In 1995, Gifford performed a cost analysis of 4 options for breech presentations at term: (1) ECV attempt on all breeches with attempted vaginal breech delivery for selected persistent breeches, (2) ECV on all breeches with cesarean delivery for persistent breech, (3) trial of labor for selected breeches with scheduled cesarean delivery for all others, and (4) scheduled cesarean delivery for all breeches prior to labor.
ECV attempt on all breeches with attempted vaginal breech on selected persistent breeches was associated with the lowest cesarean delivery rate and was the least costly approach. The second most cost-effective approach was ECV attempt on all breeches with cesarean delivery for persistent breeches.
Risks of external cephalic version
Uncommon risks of ECV include fractured bones, ruptured viscera, labor or premature rupture of membranes, abruptio placentae, fetomaternal hemorrhage (0-5%), and cord entanglement (<1.5%). A common risk of ECV is transient slowing of the fetal heart rate (as many as 40% of patients). This risk is believed to be a vagal response to head compression with ECV. It usually resolves once ECV is discontinued and has no adverse sequelae to the fetus.
Women with breech presentation at term with reassuring fetal heart rate tracing and no contraindications to vaginal delivery are candidates. ECV usually is not performed on preterm breeches because they are more likely to spontaneously vert to cephalic presentation and are more likely to revert to breech after successful ECV (approximately 50%).
No difference exists in rates of breech presentations at term or in overall cesarean delivery rates after preterm ECV.
If complications arise with ECV, a term infant can be delivered with a presumably better outcome than a preterm infant.
Absolute contraindications include multiple gestations with breech presenting, existence of contraindications to vaginal delivery (herpes simplex virus, previa), and those with nonreassuring fetal heart rate tracing.
Relative contraindications include polyhydramnios or oligohydramnios, fetal growth restriction, uterine malformation, and fetal anomaly.
Prior uterine incision: Scant data are available. In 1991, Flamm attempted ECV on 56 women with 1 or more prior low-transverse cesarean deliveries. The success rate of ECV was 82%, with successful vaginal births after cesarean in 65% of the successful ECVs. No uterine ruptures occurred during attempted ECV or subsequent labor, and no significant fetal complications occurred.
Labor: In 1985, Ferguson reported on 15 laboring women with term breeches and intact membranes. Four patients were dilated greater than 5 cm (2 women were 8 cm dilated). Ritodrine was used for acute tocolysis, and intrapartum ECV was attempted. ECV was successful in 11 of 15 cases, with 10 of 11 subsequent vaginal deliveries. No adverse effects were noted. Further studies are needed to evaluate the safety and efficacy of intrapartum ECV.
Conflicting data exist regarding the benefit of intravenous or subcutaneous beta-mimetics in improving ECV rates.
In 1996, Marquette performed a prospective randomized double-blind study on 283 women with breech presentations between 36 and 41 weeks?gestation. Subjects received either intravenous ritodrine or placebo. The success rate of ECV was 52% in the ritodrine group versus 42% in the placebo group (P = 0.35). When only nulliparous women were analyzed, significant differences were observed in the success of ECV (43% vs 25%, P <0.03). Success rates were significantly higher in parous versus nulliparous women (61% vs 34%, P <0.0001), with no additional improvement with ritodrine.
In 1999, Hofmeyr, from the Cochrane Database, reviewed 6 trials of tocolysis prior to ECV and concluded that routine tocolysis resulted in fewer failures of ECV (RR 0.77, 95% CI 0.64-0.92).
Whether tocolysis should be used routinely or selectively is still unclear.
Epidural or spinal analgesia requires analgesic levels comparable to those for cesarean delivery.
Advantages of epidural or spinal analgesia are that it allows relaxation of the anterior abdominal wall, making palpation and manipulation of the fetal head easier. Epidural or spinal analgesia eliminates pain that may cause bearing down and tensing of rectus muscles. If ECV is successful, patients can be induced with epidural in place or the epidural can be removed and the patient is sent home to await spontaneous labor. If ECV is unsuccessful, one can proceed to cesarean delivery under epidural anesthesia.
Disadvantages are the risks of regional anesthesia. Lack of maternal pain potentially results in excessive force being applied to the fetus without the knowledge of the operator. Induction after successful ECV might increase cesarean delivery risk for failed induction. Cesarean delivery following unsuccessful ECV might result in iatrogenic respiratory distress syndrome or deprive the fetus the opportunity to spontaneously vert to cephalic presentation.
In 1994, Carlan retrospectively analyzed 61 women who were at more than 36 weeks?gestation having ECV with or without epidural. The success rate of ECV was 59% in the epidural group and 24% in the no epidural group (P <0.05). In 7 of 8 women with unsuccessful ECV without epidural, repeat ECV attempt with epidural was successful. Of the epidural group, 86% had obstetrical intervention (induction or cesarean delivery) immediately after the ECV. No adverse effects on maternal or perinatal morbidity/mortality occurred.
In 1997, Schorr randomized 69 women who were at more than 37 weeks?gestation to either epidural or control prior to attempted ECV. Those in whom ECV failed underwent cesarean delivery. The success rate of ECV was 69% in the epidural group and 32% in the control group (RR 2.12, 95% CI 1.24-3.62). The cesarean delivery rate was 79% in the control group and 34% in the epidural group (P = 0.001). No complications of epidural anesthesia and no adverse fetal effects occurred.
In 1999, Dugoff randomized 102 women who were more than at 36 weeks?gestation with breech presentations to either spinal or no spinal anesthesia. All women received 0.25 mg SQ terbutaline. The success rate of ECV was 44% in the spinal group and 42% in the nonspinal group, which is not statistically significant.
Johnson and Elliott performed a randomized blinded crossover trial on 23 women comparing acoustic stimulation prior to ECV to a control group when the fetal spine was in the midline (directly back up or back down). Twelve of 12 fetuses shifted to a spine-lateral position after acoustic stimulation, and 11 (91%) underwent successful ECV, compared to 0 of 11 shifts and 1 (9%) successful ECV (P <0.0001) in the placebo group. After crossover to the alternate modality, of the 10 fetuses in whom ECV initially failed after no acoustic stimulation, all 10 shifted to spine-lateral following acoustic stimulation and 80% of these had successful ECV, compared to 0 of 1 ECV successes in the acoustic stimulation to placebo crossover.
Vaginal delivery rates after successful version
The rate of cesarean delivery ranges from 0-31% after successful ECV.
In 1994, a retrospective study by Egge of 76 successful ECVs matched with cephalic controls by delivery date, parity, and gestational age failed to note any significant difference in the cesarean delivery rate (8% in ECV group, 6% in control group).
In 1997, Lau compared 154 successful ECVs to 308 spontaneously occurring cephalic controls (matched for age, parity, and type of labor onset) with regard to cesarean delivery rate. Cesarean delivery rates were higher after ECV (16.9% vs 7.5%, P <0.005) because of higher rates of cephalopelvic disproportion and nonreassuring fetal heart rate tracing. This may be related to increased frequency of compound presentations after ECV.
Vaginal breech delivery can be performed for select cases of breech presentation after 32 weeks?gestation, although a recent randomized clinical trial suggests an increased rate of perinatal mortality and serious perinatal morbidity.
Patients must be informed of potential risks and benefits to the mother and baby of both vaginal breech delivery and cesarean delivery. The likelihood is high that the trend will continue toward 100% cesarean delivery for breeches and that vaginal breech deliveries will become a lost art.
ECV is a safe alternative to vaginal breech delivery or cesarean delivery, reducing the cesarean delivery rate for breech by 50%.
Consider adjuncts such as tocolysis, regional anesthesia, and acoustic stimulation to improve ECV success rates.
Before performing a delivery or ECV on a mother whose fetus is in a breech presentation, evaluate why the fetus is breech. The position may represent a marker for an underlying fetal anomaly.
|Caption: Picture 1. Footling breech presentation: Once the feet have delivered, there may be temptation to pull on the feet. However, this should never be done with a singleton gestation because it may precipitate an entrapped head in an incompletely dilated cervix or it may precipitate nuchal arms. As long as the fetal heart rate is stable and no physical evidence of a prolapsed cord exists, expectant management may be followed, awaiting full cervical dilatation.|
|Picture Type: Photo|
|Caption: Picture 2. Assisted vaginal breech delivery: Thick meconium passage is common as the breech is squeezed through the birth canal. This usually is not associated with meconium aspiration because the meconium passes out of the vagina and does not mix with the amniotic fluid.|
|Picture Type: Photo|
|Caption: Picture 3. Assisted vaginal breech delivery: The Ritgen maneuver is applied to take pressure off the perineum during vaginal delivery. Episiotomies often are cut for assisted vaginal breech deliveries, even in multiparous women, to prevent soft-tissue dystocia.|
|Picture Type: Photo|
|Caption: Picture 4. Assisted vaginal breech delivery: No downward or outward traction is applied to the fetus until the umbilicus has been reached.|
|Picture Type: Photo|
|Caption: Picture 5. Assisted vaginal breech delivery: With a towel wrapped around the fetal hips, gentle downward and outward traction is applied in conjunction with maternal expulsive efforts until the scapula is reached. An assistant should be applying gentle fundal pressure to keep the fetal head flexed.|
|Picture Type: Photo|
|Caption: Picture 6. Assisted vaginal breech delivery: After the scapula is reached, the fetus should be rotated 90¢X in order to delivery the anterior arm.|
|Picture Type: Photo|
|Caption: Picture 7. Assisted vaginal breech delivery: The anterior arm is followed to the elbow, and the arm is swept out of the vagina.|
|Picture Type: Photo|
|Caption: Picture 8. Assisted vaginal breech delivery: The fetus is rotated 180¢X, and the contralateral arm is delivered in a similar manner as the first. The infant is then rotated 90¢X to the back-up position in preparation for delivery of the head.|
|Picture Type: Photo|
|Caption: Picture 9. Assisted vaginal breech delivery: The fetal head is maintained in a flexed position by using the Mauriceau-Smellie-Veit maneuver, which is performed by placing the index and middle fingers over the maxillary prominence on either side of the nose. The fetal body is supported in a neutral position with care to not overextend the neck.|
|Picture Type: Photo|
|Caption: Picture 10. Piper forceps application: Pipers are specialized forceps used only for the aftercoming head of a breech presentation. They are used to keep the head flexed during extraction of the fetal head. An assistant is needed to hold the infant while the operator gets on one knee to apply the forceps from below.|
|Picture Type: Photo|
|Caption: Picture 11. Assisted vaginal breech delivery: Low 1-minute Apgar scores are not uncommon after a vaginal breech delivery. A pediatrician should be present for the delivery in the event that neonatal resuscitation is needed.|
|Picture Type: Photo|
|Caption: Picture 12. Assisted vaginal breech delivery - The neonate after birth|
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|Caption: Picture 13. Ultrasound demonstrating a fetus in breech presentation with a hyperextended head (ie, "star gazing")|
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