Singleton Breech Delivery
BS. Nguyễn Hồng Anh
CLASSIFICATION
Near term, the typical etus spontaneously assumes a cephalic presentation. However, i the etal buttocks or legs enter the pelvis beore the head, the presentation is breech. At term, breech presentation persists in 2 to 5 percent o singleton deliveries (Bin, 2016; Cammu, 2014; oijonen, 2019). Breech delivery o a second twin is discussed in Chapter 48 (p. 856).
Te categories o rank, complete, and incomplete breech presentations dier in their varying relations between the lower extremities and buttocks. With a rank breech, lower extremities are exed at the hips and extended at the knees, and thus the eet lie close to the head (Fig. 28-1). With a complete breech, both hips are exed, and one or both knees are also exed (Fig. 28-2).
With an incomplete breech, one or both hips are extended. As a result, one or both eet or knees lie below the breech, and thus a oot or knee is lowermost in the birth canal. A ootling breech is an incomplete breech with one or both eet below the breech O singleton term breech etuses, the neck may be extremely hyperextended in perhaps 5 percent, and the term stargazing etus is used (Cimmino, 1975). With transverse lie and similar hyperextension o the etal neck, the term fying etus is applied. With these, etal or uterine anomalies may be more prevalent and are sought i not previously identied (Phelan, 1983; Shipp, 2000). With hyperextension, vaginal delivery can injure the cervical spinal cord. Tus, i identied at term, cesarean delivery is indicated (Westgren, 1981). However, cases o spinal cord injury have been reported ollowing uneventul cesarean delivery o breech etuses. Here, the exion itsel may be implicated (Hernandez-Marti, 1984; Weinstein, 1983).
DIAGNOSIS
■ Risk Factors
Understanding the clinical settings that predispose to breech presentation can aid early recognition. Tis etal lie is more common remote rom term, as earlier in pregnancy each etal pole has similar bulk (oijonen, 2019). Multietal gestation is another (Chap. 48, p. 856). With singletons, other actors include extremes o amnionic uid volume, etal anomalies, structural uterine abnormalities, placenta previa, nulliparity, increased maternal age, emale etal gender, prior breech delivery, and size that is small or gestational age (Bin, 2016; Cammu, 2014; Noli, 2019; Roberts, 1999). One study ound that ollowing one breech delivery, the recurrence rate or a second breech presentation was 10 percent, and or a subsequent third breech it was 28 percent (Ford, 2010).
■ Examination
Leopold maneuvers to ascertain etal presentation are discussed in Chapter 22 (p. 419). With the rst maneuver, the hard, round etal head occupies the undus. Te second maneuver identies the hard, broad back to be on one side o the abdomen and the knobby small parts on the other. With the third maneuver, i not engaged, the soter breech is movable above the pelvic inlet. Ater engagement, the ourth maneuver shows the breech to be beneath the symphysis. Te accuracy o this palpation varies (Lydon-Rochelle, 1993; Nassar, 2006). Tus, with unclear presentation, sonographic examination is indicated. During cervical examination with a rank breech, no eet are appreciated, but the etal ischial tuberosities, sacrum, and anus are usually palpable. Ater urther etal descent, the external genitalia also may be distinguished. When labor is prolonged, the etal buttocks may become markedly swollen, rendering digital dierentiation o a ace and breech difcult. In some cases, the anus may be mistaken or the mouth and the ischial tuberosities or the malar eminences. With careul examination, however, the nger encounters muscular resistance with the anus, whereas the bony, less yielding jaws and palate are elt through the mouth. Te nger, upon removal rom the anus, may be stained with meconium. Te mouth and malar eminences orm a triangular shape, whereas the ischial tuberosities and anus lie in a straight line. With a complete breech, the eet may be elt alongside the buttocks. In ootling presentations, one or both eet are inerior to the buttocks.
Te etal sacrum is palpated to establish position. As with cephalic presentations, etal position is designated to reect the relations o the etal sacrum to the maternal pelvis. Tus, with let sacrum anterior (LSA), the etus’s back is up and its sacrum occupies the let upper (ventral) quadrant o the mother’s pelvis. Other positions are right sacrum anterior (RSA), right or let sacrum posterior (RSP or LSP), and right or let sacrum transverse (RS or LS).
DELIVERY ROUTE
Multiple actors aid determination o the best delivery route. Tese include maternal parity and pelvic dimensions; coexistent pregnancy complications; provider experience; patient preerence; hospital capabilities; and etal size, anatomy, and gestational age (Table 28-1). Compared with their term counterparts, preterm breech etuses have distinct complications related to their small size and immaturity. Accordingly, a separate discussion o term and preterm breech etuses is presented.
■ Term Breech Fetus
Current obstetrical thinking regarding vaginal delivery o the term breech etus was tremendously inuenced by results o the erm Breech rial (Hannah, 2000). Tis trial included 1041 women randomly assigned to planned cesarean and 1042 to planned vaginal delivery. Tese comparator groups reect actual risks, and the planned vaginal delivery group included those who required intrapartum cesarean delivery. In the planned vaginal delivery group, 57 percent were actually delivered vaginally. Planned cesarean delivery was associated with a lower risk o perinatal mortality compared with planned vaginal delivery—3 per 1000 versus 13 per 1000. Cesarean delivery was also associated with a lower risk o “serious” neonatal morbidity—1.4 versus 3.8 percent. Short-term maternal morbidity was similar between groups.
Critics o the erm Breech rial emphasize that ewer than 10 percent o candidates underwent radiological assessment o pelvic capacity. In addition, most o the outcomes included in the “serious” neonatal morbidity composite did not actually portend long-term inant disability (Whyte, 2004). Since that trial, however, additional data avoring cesarean delivery has come rom the World Health Organization ( Lumbiganon, 2010). In more than 100,000 deliveries rom nine participating Asian countries, planned cesarean delivery oered improved perinatal outcomes or the term breech etus compared with planned vaginal delivery. Other studies also have ound lowered neonatal morbidity and mortality rates with cesarean delivery (Lyons, 2015; Rietberg, 2005; Vistad, 2015).
From one metaanalysis, the calculated absolute risk o perinatal mortality was 0.3 percent, and risk o etal birth trauma or neurological morbidity was 0.7 percent (Berhan, 2016). In contrast, other studies support vaginal delivery as a suitable option at term (Homeyr, 2015a). Te Presentation et Mode d’Accouchement (PREMODA) study—which translates as presentation and mode o delivery—showed no dierences in corrected neonatal mortality rates and neonatal outcomes according to delivery mode (Gofnet, 2006). Severe acute maternal morbidity scores were similar (Korb, 2019). Tis French prospective observational study involved more than 8000 women with term breech singletons. Strict criteria were used to select 2526 o these or planned vaginal delivery, and 71 percent o that group were delivered vaginally. Data rom the Lille Breech Study Group in France also showed no excessive morbidity in term breech singletons delivered vaginally provided that strict etal biometric and maternal pelvimetry parameters were applied (Michel, 2011). Other smaller studies support these ndings as long as guidelines are part o the selection process (Alarab, 2004; Giuliani, 2002; oivonen, 2012).
Long-term evidence supporting vaginal breech delivery comes rom Eide and associates (2005). Tese investigators analyzed intelligence testing scores o more than 8000 men delivered breech, and delivery route did not aect later intellectual perormance. Moreover, a 2-year ollow-up rom the erm Breech trial showed similar risks or death and or neurodevelopmental delay between delivery groups (Whyte, 2004). Other studies support these ndings (Bin, 2017; Macharey, 2018). Despite evidence or this debate, at least in the United States, rates o planned vaginal delivery attempts continue to decline (Grunebaum, 2016). Tus, as predicted, the number o skilled providers able to saely select and vaginally deliver breech etuses steadily dwindles (Dotters-Katz, 2020). Moreover, obvious medicolegal concerns make physician training in such deliveries difcult. In response, some institutions have developed birth simulators to improve resident competence in vaginal breech delivery (Deering, 2006; Maslovitz, 2007).
In selecting suitable term breech vaginal delivery candidates,
actors outlined in able 28-1 are weighed. O these, various
national organizations recommend that the estimated term etal
weight lies between >2500 to 2800 g and <3800 to 4000 g
(American College o Obstetricians and Gynecologists, 2018b;
Impey, 2017b; Kotaska, 2019). Fetal-growth restriction and
oligohydramnios are other contraindications, because o their
inherent association with poor neonatal outcome (Chaps. 14
and 47, pp. 260 and 831). Data support this concern or the
term breech etus (Hinnenberg, 2019; Macharey, 2017a). O
uterine actors, prior hysterotomy carries an inherent risk or
rupture in labor. Te PREMODA, erm Breech rial, and
other studies allowed a trial o labor ater cesarean or vaginal
breech delivery, but in each, these constituted a small percentage o participants. Other studies have considered prior cesarean as a contraindication. Very limited data suggest a possible
link with adverse perinatal outcome (Azria, 2012; Macharey,
2017a). Moreover, a prior cesarean delivery perormed or
arrested labor may suggest a relatively contracted pelvis and a
greater labor risk. In contrast, parity and prior vaginal birth
are positive actors and likely reect sufcient pelvic capacity.
Last, those with spontaneous labor and normal labor curves
have higher successul vaginal birth rates.
■ Preterm Breech Fetus
In contrast to the term breech etus, no randomized trials guide
delivery selection or the preterm breech etus. Comparison o
the available observational studies is oten hampered by their
combining, splitting, or overlapping o gestational age groups.
Other study biases include diering gestational age thresholds
or planned neonatal resuscitation, assigning mortality causation to delivery rather than immaturity, and tendency to avor
vaginal delivery or etuses with a poor prognosis. In addition,
the eects o precipitous vaginal delivery and associated incomplete antenatal prophylaxis with corticosteroids and antibiotics
is difcult to evaluate.
Despite these limitations, or preterm breech etuses as
whole, data support that planned cesarean delivery coners a
survival advantage compared with planned vaginal delivery.
Reddy and associates (2012) reported data rom deliveries
between 24 and 32 weeks’ gestation. For breech etuses within
these gestational ages, attempting vaginal delivery yielded a low
success rate, and this group was associated with higher neonatal mortality rates compared with planned cesarean delivery.
From a metaanalysis incorporating data rom more than
3500 parturients, similar mortality associations were reported
( Bergenhenegouwen, 2014). In contrast, in their smaller cohort
with gestational ages o 26 to 34 weeks, Lorthe and coworkers
(2019) ound similar rates o survival or o survival at discharge
without severe morbidity.
For less mature subgroups—23 to 28 weeks—the data are
more conicting as to whether survival rates are improved with
planned cesarean delivery (Bergenhenegouwen, 2015; Grabovac,
2018; Kayem, 2015; Tomas, 2016; ucker Edmonds, 2015).
In the balance, cesarean delivery is proposed to avoid etal
injury rom vaginal birth that may include anoxia, trauma,
and head entrapment. Tis is measured against maternal morbidity rom a classical uterine incision, which is oten needed
in this early preterm group due to a poorly developed lower
uterine segment. Tis incision typically poses a risk o greater
blood loss, higher inection rate, and increased risk o uterine
rupture in uture pregnancies (Patterson, 2002; Reddy, 2015;
Sciscione, 2008). Te high-level skills needed or sae vaginal
delivery o the very preterm etus and the ultimate prognosis
o the neonate are other directing actors. For periviable etuses,
dened by them as 20 to 256/7 weeks, a consensus workshop
o perinatal organizations concluded that “available data do
not consistently support routine cesarean delivery to improve
perinatal mortality or neurological outcomes or early preterm
inants” (Raju, 2014). A subsequent joint statement by the
American College o Obstetricians and Gynecologists and the
Society or Maternal-Fetal Medicine (2017) suggested consideration or cesarean delivery or periviable etuses beginning
at 230/7 weeks, with a recommendation or cesarean delivery
at 250/7 weeks.
For more mature preterm breech etuses, that is, between
32 and 37 weeks, again limited data guide delivery route selection. Bergenhenegouwen and coworkers (2015) studied more
than 6800 breech deliveries in a subgroup between 32 and 37
weeks. With planned cesarean delivery or planned vaginal birth,
they ound similar perinatal mortality and morbidity rates.
All these ndings shape practice. Tus, individualized decision-making is needed or the preterm breech etus or whom
resuscitation is planned. Provider skill, gestational age, parity,
labor curve, and acility capability weigh heavily in this process. For the etus in which resuscitation is not planned, vaginal
delivery is likely preerable.
■ Delivery Complications
Compared with cephalic-presenting etuses, higher rates o
maternal and perinatal morbidity can be anticipated with
breech presentations. For the mother, with either cesarean or
vaginal delivery, genital tract laceration can be problematic.
With cesarean delivery, added stretching o the lower uterine
segment by orceps or by a poorly molded etal head can extend
hysterotomy incisions. With vaginal delivery, especially with a
thinned lower uterine segment, delivery o the atercoming head
through an incompletely dilated cervix or application o orceps
may cause vaginal wall or cervical lacerations, and even uterine
rupture. Manipulations may also extend an episiotomy, create
deep perineal tears, require cervical incision, and raise inection
risks. I needed in select cases, inhalant anesthesia sufcient to
induce appreciable uterine relaxation during vaginal delivery
may cause uterine atony and postpartum hemorrhage. Maternal death is rare, but rates appear higher in those with planned
cesarean delivery or breech presentation—a case-atality rate o
0.47 maternal deaths per 1000 births (Schutte, 2007). Other
general short-term and long-term risks o cesarean delivery are
listed in Chapter 30 (p. 548).
For the etus, prematurity and its complications are requently comorbid with breech presentation. Rates o congenital anomalies also are greater (Mostello, 2014). Compared
with cephalic presentation, umbilical cord prolapse is more
requent with breech etuses and with breech vaginal delivery
( Behbehani, 2016; Critchlow, 1994). Collea (1980) reported
that the incidence o prolapse approximated 0.5 percent with
rank breech presentation, 5 percent with complete breech, and
up to 15 percent with ootling presentation.
Rare etal morbidity includes humeral or clavicular racture,
brachial plexus injury, and sternocleidomastoid muscle trauma
(Chap. 33, p. 609. Tese may occur with either route but more
requently complicate vaginal birth. However, cesarean birth
does not appear to aord greater protection against emur or
skull ractures (Ekéus, 2019; Gofnet, 2006; Hannah, 2000).
Rarely, traction may separate scapular, humeral, or emoral
epiphyses (Lamrani, 2011). Te spinal cord may be injured or
vertebrae ractured, especially i great orce is employed (Vialle,
2007). Last, genitals may be injured with breech delivery
(Saroha, 2015).
Some perinatal outcomes are inherent to the breech position
rather than delivery. For example, development o hip dysplasia is more common in breech compared with cephalic presentation and is unaected by delivery mode (de Hundt, 2012;
Hinderaker, 1994).
■ Imaging
As noted, limited sonographic evaluation near term is reasonable to conrm presentation. ransabdominal sonography o
the lower uterine segment in the sagittal plane shows the presenting etal part. Prior to this and as part o prenatal care,
sonographic etal survey will have been perormed in most
cases. I not, gross etal abnormalities, such as hydrocephaly or
anencephaly, can be rapidly ascertained with sonography. Tis
will identiy many etuses not suitable or vaginal delivery. It
will also help to ensure that a cesarean delivery is not perormed
under emergency conditions or an anomalous etus with no
chance o survival.
In many etuses—especially those that are preterm or growth
restricted—the breech is smaller than the atercoming head.
Moreover, unlike cephalic presentations, the head o a breechpresenting etus does not undergo appreciable molding during
labor. Tus, i vaginal delivery is considered, etal size, breech
type, and degree o neck exion are evaluated (Fontenot, 1997;
Rojansky, 1994). I needed, simple two-view radiography o
the maternal abdomen also can dene etal head inclination.
Sonographic identication o a nuchal arm or nuchal cord
loops may warrant cesarean delivery to avoid neonatal harm
(Sherer, 1989).
Te accuracy o etal weight estimation by sonography is
not altered by breech presentation (McNamara, 2012). For
planned vaginal delivery at term, thresholds in able 28-1
guide care. Moreover, a biparietal diameter (BPD) >90 to
100 mm is oten considered exclusionary or vaginal delivery
(Giuliani, 2002; Roman, 2008).
Pelvimetry
In addition to these requisite etal parameters, some institutional protocols recommend pelvimetry to assess the maternal
bony pelvis prior to planned vaginal term breech birth. Others,
including our practice at Parkland Hospital, instead monitor
the steady progression o etal descent and cervical dilation to
reect adequate pelvic capacity.
For pelvimetry, one-view computed tomography (C),
magnetic resonance (MR) imaging, or plain lm radiography
is suitable. Comparative data among these modalities or pelvimetry are lacking, but C is avored due to its accuracy, low
radiation dose, and widespread availability (Tomas, 1998).
Although variable, some suggest specic measurements to permit a planned vaginal delivery: inlet anteroposterior diameter
≥10.5 cm; inlet transverse diameter ≥12.0 cm; and midpelvic interspinous distance ≥10.0 cm (Azria, 2012; Vendittelli,
2006). Some have recommended maternal-etal biometry
correlation. Appropriate values include: the sum o the inlet
obstetrical conjugate minus the etal BPD is ≥15 mm; the inlet
transverse diameter minus the BPD is ≥25 mm; and the midpelvis interspinous distance minus the BPD is ≥0 mm (Michel,
2011). From small studies o MR imaging, vaginal delivery success rates approximating 75 percent were noted i the interspinous distance was >11 cm and true obstetrical conjugate was
>12 cm (Homann, 2016; Klemt, 2019).
LABOR AND DELIVERY
■ Labor Management
On arrival to the labor unit, surveillance o etal heart rate and
uterine contractions begins, and immediate recruitment o necessary sta includes: (1) a provider skilled in the art o breech
extraction, (2) an associate to assist with the delivery, (3) anesthesia personnel who can ensure adequate analgesia or anesthesia
when needed, and (4) an individual trained in newborn resuscitation. For the mother, intravenous access is obtained. Tis
allows, i required, emergency induction o anesthesia or maternal resuscitation ollowing hemorrhage rom lacerations or rom
uterine atony.
Assessing cervical dilation, membranes status, and presenting part station is essential or management. I labor is too
ar advanced, pelvimetry may be unsae i etal expulsion in
the radiology department is a possibility. Tis alone, however,
should not orce the decision or cesarean delivery. Commonly,
stepwise labor progression itsel is a good indicator o pelvic
adequacy (Biswas, 1993). Sonographic assessment, described
earlier, is completed. Ultimately, the choice o abdominal or
vaginal delivery is guided by actors listed in able 28-1.
During labor, one-on-one nursing is ideal because o
increased cord prolapse risks, and physicians must be readily
available or such emergencies. Guidelines or monitoring the
high-risk etus are applied (Chap. 24, p. 461). For rst-stage
labor, most clinicians preer continuous electronic monitoring.
At minimum, the etal heart rate is recorded every 15 minutes. A scalp electrode can be saely afxed to the buttock, but
genitalia are avoided.
When membranes rupture, either spontaneously or arti-
cially, the cord prolapse risk rises appreciably. A small or preterm etus or a non-rank breech presentation raises this risk.
Tereore, vaginal examination is perormed immediately ollowing rupture, and special attention is directed to the etal
heart rate or the rst 5 to 10 minutes thereater.
Continuous epidural analgesia is advocated by some. Tis
may increase the need or labor augmentation and prolong second-stage labor (Chadha, 1992; Conno, 1985). Tese potential disadvantages are weighed against the advantages o better
pain relie and increased pelvic relaxation should extensive etal
manipulation be required. Analgesia must be sufcient or episiotomy, or breech extraction, and or Piper orceps application. Nitrous oxide plus oxygen inhalation provides urther
relie rom pain. I general anesthesia is required, it must be
induced quickly.
Normal second-stage labor should show progressive etal
descent. An initial passive second stage allows the breech to
advance to the perineum and is recommended. In the PREMODA
study, this stage lasted <30 min or 60 percent o parturients and
>60 min or only 20 percent (Gofnet, 2006). For this passive
phase, some recommend cesarean i the breech is not visible ater
1½ to 2 hours (Impey, 2017b; Kotaska, 2019).
Once the breech is visible, active pushing is encouraged. A
hands-o approach in which hands are poised merely to support delivering parts is preerred to allow spontaneous delivery.
In the PREMODA study, this active phase was <30 min or
95 percent o those with successul vaginal births (Gofnet,
2006). In their subanalysis o adverse neonatal outcome actors, an active second stage >20 min increased the risk (Azria,
2012). In the erm Breech rial, the lowest risk or maternal and neonatal adverse outcomes was seen in the group with
active second stages lasting <30 min (Su, 2003, 2007). In one
small observational study, etal adverse risks rose i this phase
was >40 minutes (Macharey, 2017b). Canadian guidelines
recommend cesarean i completed or imminent delivery is not
accomplished ater 60 min o pushing (Kotaska, 2019).
■ Labor Induction or Augmentation
Induction or augmentation o labor is controversial or term
breech pregnancies. Here again, data are limited and mostly
retrospective. With labor induction, Burgos and coworkers
(2017) reported equivalent vaginal delivery rates compared with
spontaneous labor. With induction, however, they reported
higher rates o neonatal intensive care unit (NICU) admission.
But, Marzouk and associates (2011) ound perinatal outcomes
and cesarean delivery rates not to dier. Last, others described
greater cesarean delivery rates with induction but similar neonatal outcomes (Macharey, 2016). In a metaanalysis o studies,
the NICU admission rate was 3 percent with labor induction
and was double that o those delivered rom spontaneous labor.
Te cesarean delivery rate with induction was higher and was
33 percent (Sun, 2018).
Compared with cephalic presentations, breech labor in
general proceeds more slowly, but steady cervical progress is a
positive indicator o adequate pelvic capacity (Lennox, 1998).
Tus, some protocols avoid augmentation or the breech-presenting etus, whereas others recommend it only or hypotonic
contractions (Alarab, 2004; Kotaska, 2019). In women with a
viable etus, at Parkland Hospital, we use amniotomy to promote contractions but preer cesarean delivery instead o pharmacological labor induction or augmentation.
■ Vaginal Delivery Methods
Vaginal breech delivery is accomplished by one o three methods.
With spontaneous breech delivery, the etus is expelled entirely
without any traction or manipulation other than support o the
newborn. With partial breech extraction, the etus is delivered
spontaneously as ar as the umbilicus, but the remainder o the
body is delivered by provider traction and assisted maneuvers,
with or without maternal expulsive eorts. With total breech
extraction, the entire etal body is extracted by the provider.
■ Spontaneous Breech Delivery
FIGURE 28-3 To deliver the left leg, two fingers of the provider’s left hand are placed beneath and parallel to the femur. The thigh is then slightly abducted and pressure from the fingertips in the popliteal fossa should induce knee flexion and bring the foot within reach. The foot is then grasped to gently deliver the entire leg outside the vagina. A similar procedure is followed on the right. (Reproduced with permission from Yeomans ER: Vaginal breech delivery. In Yeomans ER, Hoffman BL, Gilstrap LC III, et al [eds]: Cunningham and Gilstrap’s Operative Obstetrics, 3rd ed. New York, NY: McGraw Hill; 2017.)
Obstetrics, 3rd ed. New York, NY: McGraw Hill; 2017.)
Similar to vertex delivery, spontaneous expulsion o a breech
etus entails sequential cardinal movements (Chap. 22, p. 421).
First, engagement and descent o the breech usually take place
with the bitrochanteric diameter in one o the oblique pelvic
diameters. Te anterior hip usually descends more rapidly than
the posterior hip, and when the resistance o the pelvic oor is
met, internal rotation o 45 degrees usually ollows, bringing
the anterior hip toward the pubic arch and allowing the bitrochanteric diameter to occupy the anteroposterior diameter o
the pelvic outlet.
Ater rotation, descent continues until the perineum is distended by the advancing breech, and the anterior hip appears
at the vulva. By lateral exion o the etal body, the posterior
hip then is orced over the perineum, which retracts over the
etal buttocks, thus allowing the etus to straighten out when
the anterior hip is born. Te legs and eet ollow the breech and
may be born spontaneously or require aid.
Ater the birth o the breech, there is slight external rotation,
with the back turning anteriorly as the shoulders are brought
into relation with one o the oblique diameters o the pelvis. Te
shoulders then descend rapidly and undergo internal rotation,
with the bisacromial diameter occupying the anteroposterior
plane. Immediately ollowing the shoulders, the head, which is
normally sharply exed on the thorax, enters the pelvis in one
o the oblique diameters and then rotates to bring the posterior
portion o the neck under the symphysis pubis. Te head is then
born in exion.
Inrequently, rotation renders the etal back to lie posteriorly instead o anteriorly. Such rotation is prevented i possible.
Although the head can be delivered by allowing the chin and
ace to pass beneath the symphysis, the slightest traction on
the body may cause extension o the head. With this, a longer
diameter o the head must pass through the pelvis.
■ Partial Breech Extraction
With breech delivery, successively larger and less compressible
parts are born. Tus, spontaneous expulsion is the exception,
and vaginal delivery typically requires skilled provider participation or the etus to navigate the birth canal. Noteworthy
clinical pearls are provided by Yeomans (2017) in Cunningham
and Gilstrap’s Operative Obstetrics, 3rd edition.
First, with all breech deliveries, unless the perineum is considerably lax, an episiotomy is made and is an important adjunct
to delivery. As discussed in Chapter 27 (p. 510), mediolateral
episiotomy may be preerred or its lower associated risk o anal
sphincter lacerations. Ideally, the breech is allowed to deliver
spontaneously to the umbilicus. Delivery o the breech draws
the umbilicus and attached cord into the pelvis. Tereore, once
the breech has passed beyond the vaginal introitus, the abdomen, thorax, arms, and head must be delivered promptly either
spontaneously or assisted.
Te posterior hip will deliver, usually rom the 6 o’clock
position, and oten with sufcient pressure to evoke passage o
thick meconium. Te anterior hip then delivers, ollowed by
external rotation to a sacrum anterior position. Te mother is
encouraged to continue to push as the etus descends until the
legs are accessible. Te legs are sequentially delivered by splinting the emur with the operator’s ngers positioned parallel to
the long axis o the emur. Tis helps avoid emoral racture.
Pressure is exerted upward and laterally to sweep each leg away
rom the midline (Fig. 28-3).
Following delivery o the legs, the etal bony pelvis is grasped
with both hands. Te ngers should rest on the anterior superior iliac crests and the thumbs on the sacrum. Tis minimizes
the chance o etal abdominal sot-tissue injury (Fig. 28-4).
Maternal expulsive eorts are again used in conjunction with
downward traction to aect delivery.
A cardinal rule in successul breech extraction is to employ
steady, gentle, downward traction until the lower halves o the
scapulas are delivered. Subsequent delivery o the shoulders
and arms is not attempted until one axilla becomes visible. It
makes little dierence which shoulder is delivered rst, and
two methods are suitable or their delivery. In the rst method,
with the scapulas visible, the trunk is rotated either clockwise or
counterclockwise to bring the anterior shoulder and arm into
view (Fig. 28-5). During delivery o the arm, ngers and hand
are aligned parallel to the humerus and act as a splint. Perpendicular orce risks humeral racture. Te body o the etus is
then rotated 180 degrees in the reverse direction to bring the
other shoulder and arm into position or delivery.
Te second method is employed i trunk rotation is unsuccessul. With this maneuver, the posterior shoulder is delivered rst. For this, the eet are grasped in one hand and
drawn upward over the inner thigh o the mother (Fig. 28-6).
Te operator’s hand enters over the etal shoulder, ngers are
aligned parallel to the long axis o the etal humerus, and the
etal arm is swept upward. Te posterior shoulder slides out
over the perineal margin and is usually ollowed by the arm and
hand. Ten, by depressing the body o the etus, the anterior
shoulder emerges beneath the pubic arch, and the arm and hand
usually ollow spontaneously. Ater both shoulders are delivered,
the back o the etus tends to rotate spontaneously to the symphysis. Delivery o the head may then be accomplished.
Nuchal Arm
During delivery, one or both etal arms occasionally may lie
across the back o the neck and become trapped at the pelvic inlet. With such a nuchal arm, delivery is more difcult
and can be aided by rotating the etus through a hal circle
in such a direction that the riction exerted by the birth canal
will draw the elbow toward the ace (Fig. 28-7). With a right
nuchal arm, the body should be rotated counterclockwise,
which rotates the etal back toward the maternal right. With
a let nuchal arm, the rotation is clockwise, which rotates the
etal back toward the maternal let. I rotation ails to ree the
nuchal arm, it may be necessary to push the etus upward to a
roomier part o the pelvis. I the rotation is still unsuccessul,
still in this roomier part o the pelvic, the nuchal arm can be
extracted. For this, the operator’s hand enters over the etal
shoulder, and ngers are aligned parallel to the long axis o the
etal humerus. Downward pressure exes the elbow, and the
etal arm is then swept orward
and down the ventral body sur-
ace or delivery. In this event,
racture o the humerus or clavicle is common.
Delivery of the
Aftercoming Head
Te head o the etus is normally
extracted with one o the three
maneuvers. With any o these,
hyperextension o the etal neck
is avoided.
First, with the Mauriceau
maneuver, the index and middle
nger o one hand are applied
over the maxilla, to ex the head,
while the etal body rests on
the palm o the same hand and
orearm (Fig. 28-8). Fetal legs
straddle the orearm. wo ngers o the other hand hook over
and grasp the shoulders. Downward traction is concurrently
applied until the suboccipita
region appears under the symphysis. Gentle suprapubic pressure simultaneously applied by an assistant helps keep the head
exed. Te body is slightly elevated toward the maternal abdomen, and the mouth, nose, brow, and eventually the occiput
emerge successively over the perineum. With this maneuver,
the provider uses both hands simultaneously to exert continuous downward gentle traction while balancing orces between
the etal neck and maxilla to avoid neck hyperextension
Second, specialized orceps can be used to deliver the atercoming head. Piper orceps, shown in Figure 28-9, or Laue-Piper
orceps may be applied electively or when the Mauriceau maneuver cannot be accomplished easily. Te blades o the orceps are
not applied to the atercoming head until it has been brought
into the pelvis by gentle traction, combined with suprapubic
pressure, and is engaged. Suspension o the body o the etus in a
towel eectively holds the etus up and helps keep the arms and
cord out o the way as the orceps blades are applied.
Because the orceps blades are directed upward rom the level o
the perineum, some choose to apply them rom a one-knee kneeling position. Piper orceps have a downward arch in the shank to
accommodate the etal body and lack a pelvic curve. Tis shape
permits direct application o the cephalic curve o the blade along
the length o the maternal vagina and etal parietal bone. Te blade
to be placed on the maternal let is held in the provider’s let hand.
Te right hand slides between the etal head and let maternal
vaginal sidewall to guide the blade inward and around the parietal
bone. Te opposite blade mirrors this application.
Once in place, the blades are articulated, and the etal body
rests across the shanks. Te head is delivered by pulling gently
outward and slightly raising the handle simultaneously. Tis
rolls the ace over the perineum, while the occiput remains
beneath the symphysis until ater the brow delivers. Ideally, the
head and body move in unison to minimize neck extension.
Last, in some cases, the back o the etus ails to rotate to the
symphysis. Te etus still may be delivered using the modied
Prague maneuver. With this, two ngers o one hand grasp the
shoulders o the back-down etus rom below while the other hand
draws the eet up and over the maternal abdomen (Fig. 28-10).
the fetal head is being delivered, flexion of the head is maintained by suprapubic pressure provided
by an assistant. B. Pressure on the maxilla is applied simultaneously by the operator as upward and
outward traction is exerted.
Head Entrapment
Either an incompletely dilated cervix or cephalopelvic disproportion can entrap the head. At this point, a true emergency
exists because signicant cord compression must be assumed.
First, an incompletely dilated cervix can constrict around
the neck, especially with a small preterm etus. With gentle
traction on the etal body, the cervix at times may be manually slipped over the occiput. I unsuccessul, Dührssen incisions may be needed (Fig. 28-11). General anesthesia with
halogenated agents is another option to aid lower uterine segment relaxation. As an extreme measure, replacement o the
etus higher into the vagina and uterus, ollowed by cesarean
delivery, can rescue an entrapped breech etus. Tis Zavanelli
maneuver is classically perormed to relieve intractable shoulder dystocia (Sandberg, 1988). However, case reports have also
described its use or an entrapped atercoming head (Sandberg,
1999; Steyn, 1994).
Second, in cases with cephalopelvic disproportion and arrest
o atercoming head, the Zavanelli maneuver or symphysiotomy are options (Sunday-Adeoye, 2004; Wery, 2013). Tese
are described in Chapter 27 (p. 504).
FIGURE 28-11 Dührssen incision being cut at 2 o’clock, which is followed by a second incision if needed at 10 o’clock. Infrequently, an additional incision is required at 6 o’clock. The incisions are so
placed as to minimize bleeding from the laterally located cervical branches of the uterine artery. After delivery, the incisions are repaired as described in Chapter 42 (p. 740).
■ Total Breech Extraction
Frank Breech
During complete extraction o a rank breech, moderate
traction is exerted by a nger in each groin and aided by a
generous episiotomy. Once the breech is pulled through the
introitus, the steps just described or partial breech extraction
are completed.
Rarely during vaginal delivery, a rank breech will require
decomposition inside the uterine cavity. Attributed to Pinard
(1889), this procedure converts a rank breech into a ootling
breech. It is accomplished more readily i the membranes have
ruptured only recently. It becomes extremely difcult i amnionic uid is scant and the uterus is tightly contracted around
the etus. Pharmacological relaxation by general anesthesia or
intravenous magnesium sulate, nitroglycerin, or a betamimetic
agent may be required. o begin, two ngers are carried up
along one leg to externally rotate the hip by pressing on the
medial side o the thigh parallel to the emur. Simultaneously,
pressure in the popliteal ossa should prompt spontaneous knee
exion which brings the corresponding oot into contact with
the back o the provider’s hand. Te etal oot then may be
grasped and brought down. Delivery is then accomplished as
or incomplete breech, described next.
Incomplete or Complete Breech
I rapid labor progress prohibits cesarean delivery, total extraction
o an incomplete or complete breech may be required. A hand is
introduced through the vagina, and both etal eet are grasped.
Te ankles are held with the middle nger lying between them.
With gentle traction, the eet are brought through the introitus
(Fig. 28-12). As the legs begin to emerge through the vulva,
downward gentle traction is continued. As the legs emerge, successively higher portions are grasped. When the breech appears
at the vaginal outlet, gentle traction is applied until the hips are
delivered. Te thumbs are then placed over the sacrum and the
ngers over the iliac crests. Breech extraction is then completed,
as described or partial breech extraction.
I only one oot can be grasped, it can be brought down into
the vagina and held with the appropriate hand, right hand or
right oot and let hand or let oot (Yeomans, 2017). With the
rst oot secure, the opposite hand is introduced, passed upward
along the leg, and guided to locate the other oot. I the remaining hip is extended, the second oot is usually easily grasped and
brought down. I the hip is exed and knee extended, a nger is
hooked into that groin, and traction will bring the lower hal o
the etus down until the leg can be reached.
For cesarean delivery, these same total breech extraction
maneuvers can be used. Tese steps can aid delivery o a rank,
complete, or incomplete breech through the hysterotomy
incision.
EXTERNAL CEPHALIC VERSION
With version, etal presentation is altered by physically substituting one pole o a longitudinal presentation or the other,
or converting an oblique or transverse lie into a longitudinal
presentation. Manipulations perormed through the abdominal wall that yield a cephalic presentation are termed external
cephalic version. Manipulations accomplished inside the uterine
cavity that yield a breech presentation are designated internal
podalic version. Tis latter procedure is reserved or delivery o
a second twin and described in Chapter 48 (p. 856).
■ Indications
External cephalic version (ECV) reduces the rate o noncephalic presentation at birth, and its success rate is 50 to 60
percent (Homeyr, 2015b; Melo, 2019). For women with a
transverse lie, the overall success rate is signicantly higher.
In general, ECV is attempted beore labor in a woman who
has reached 370/7 weeks’ gestation (American College o Obstetricians and Gynecologists, 2020; Impey, 2017a). Tis threshold
aims to balance risks o etal immaturity and the greater amnionic
uid volume seen in early-term pregnancies, which aids turning.
In support o this, one systematic review ound that ECV done
beore 370/7 weeks raised ECV success rates but did not lower
the ultimate cesarean delivery rate and increased the risk o latepreterm birth (Hutton, 2015). Beore this time, breech presentation also still has a high likelihood o correcting spontaneously.
And, i ECV is perormed too early, time may allow a reversion
back to breech (Bogner, 2012). Last, i attempts at version cause
a need or immediate delivery, complications o iatrogenic earlyterm delivery generally are not severe.
Absolute contraindications to ECV are ew. It is contraindicated i vaginal delivery is not an option, such as with placenta
previa. Relative contraindications are early labor, oligohydramnios
or ruptured membranes, known nuchal cord, structural uterine
abnormalities, etal-growth restriction, multietal gestation, and
prior abruption or its risk actors (Rosman, 2013). Little data
guide the decision or ECV or women with a prior cesarean delivery. In one pooled series o small studies that contained more than
100 attempts, no uterine ruptures were reported (Impey, 2018).
At Parkland Hospital, we do not attempt ECV in these women.
Several actors can improve the chances o an ECV attempt.
Tese are multiparity, unengaged presenting part, nonanterior placenta, nonobese patient, and abundant amnionic uid
(Lauterbach, 2021; Kok, 2008, 2009). o augment the last
parameter, neither a preprocedural 2-L intravenous uid bolus
nor amnioinusion raised ECV success rates (Burgos, 2014;
Diguisto, 2018). Dedicated breech teams may increase these
rates (Hickland, 2018; Tissen, 2019).
■ Complications
Patient counseling includes a discussion regarding small but
real risks or placental abruption, preterm labor, and etal compromise. Bradycardia is common during or ollowing ECV,
but emergent cesarean rates are ≤0.5 percent. Uterine rupture,
etomaternal hemorrhage, alloimmunization, amnionic uid
embolism, and maternal or etal deaths are rare (Grootscholten,
2008; Rodgers, 2017). Overall, compared with expectant management, perinatal morbidity and mortality rates are not greater
with ECV (Krueger, 2018; Son, 2018).
Even ater successul ECV, several reports suggest that the
cesarean delivery rate does not completely revert to the baseline
or vertex presentations. Specically, dystocia, malpresentation,
and nonreassuring etal heart patterns may be more common
in these etuses who have undergone successul ECV (Chan,
2004; de Hundt, 2014; Vézina, 2004).
■ Technique
ECV should be carried out in an area that has ready access
to a acility equipped to perorm emergency cesarean delivery.
Because o the risk or surgical intervention, intravenous access
is obtained. Patients also abstain rom eating or 6 hours, but
clear liquids can be consumed up to 2 hours prior. Sonographic
examination is perormed to conrm nonvertex presentation,
document amnionic uid volume adequacy, exclude obvious
etal anomalies i not done previously, and identiy placental
location and etal spine orientation. Preprocedural external
monitoring is perormed to document etal heart rate reactivity.
Anti-D immune globulin is given to Rh D–negative women.
ocolysis and regional analgesia may be elected, and rationale
or these is provided in subsequent sections.
Te woman is placed in let lateral tilt to aid uteroplacental
perusion, and rendelenburg positioning helps during elevation o the breech. During the procedure, we preer to monitor
etal heart motion sonographically. An abundant abdominal
coating o ultrasound gel permits this and also minimizes painul
skin riction (Vallikkannu, 2014).
A orward roll o the etus usually is attempted rst. One or
two providers may participate, and one hand grasps the head.
Te etal buttocks are then elevated rom the maternal pelvis and displaced laterally (Fig. 28-13). Tese are then gently
guided toward the undus, while the head is simultaneously
directed toward the pelvis. I the orward roll is unsuccessul,
a backward ip is attempted. ECV attempts are discontinued or excessive discomort, or persistently abnormal etal
heart rate, or ater multiple ailed attempts. Failure is not
always absolute. Ben-Meir and colleagues (2007) reported a
spontaneous version rate o 7 percent among 226 ailed versions—2 percent among nulliparas and 13 percent among
multiparas.
I ECV is successul, a nonstress test is repeated until a normal test result is obtained. A transient abnormal etal heart rate
tracing during or ater ECV complicates 6 to 9 percent o cases.
Tis should prompt a traditional resuscitative response with
intravenous uids, oxygen, and lateral tilt. Rates o abnormal
tracings prompting immediate cesarean delivery range rom
only 0.2 to 0.4 percent ( Collaris, 2004; Grootscholten, 2008).
Once resolved, Kuppens and coworkers (2017) ound that a
transient abnormal tracing did not predict later etal distress in
subsequent labor.
I ECV is completed beore 39 weeks’ gestation, awaiting
spontaneous labor and etal maturity is preerred. In some
studies, immediate labor induction is linked to higher cesarean
delivery rates (Burgos, 2015; Kuppens, 2013).
FIGURE 28-13 External cephalic version. With an attempted forward roll, clockwise pressure is exerted against the fetal poles.
Tocolysis
By relaxing the uterus prior to an ECV attempt, tocolysis raises
success rates. Most data support the use o the betamimetics
terbutaline and ritodrine or this (Cluver, 2015). In one such
trial, Fernandez and coworkers (1996) reported that the success rate with subcutaneous terbutaline—52 percent—was
signicantly higher than without—27 percent. Our policy at
Parkland Hospital is to administer 250 μg o terbutaline subcutaneously to most women beore attempted ECV. When maternal tachycardia—a known side eect o terbutaline—is noted,
the attempt is begun. erbutaline readily crosses the placenta,
and mild elevation o etal heart rate baseline also is possible
(Ingemarsson, 1981; Roth, 1990). Data are limited and in some
cases are nonsupportive or other agents that include calciumchannel blockers, such as niedipine; nitric oxide donors, such
as nitroglycerin; the oxytocin-receptor antagonist atosiban; and
another betamimetic salbutamol (Burgos, 2010; Cluver, 2015;
Hilton, 2009; Levin, 2019; Vani, 2009; Wilcox, 2011).
Conduction Analgesia
Epidural analgesia coupled with tocolysis has been reported
to raise ECV success rates compared with tocolysis alone
( Goetzinger, 2011; Magro-Malosso, 2016). Moreover, rates o
complications that include etal heart rate aberrations, emergency cesarean delivery, or placental abruption are not greater
with regional analgesia. In trials, spinal and epidural have both
shown success and are reasonable options (Khaw, 2015; Weiniger, 2010). Although uncommon, risks specic to regional
analgesia, such as spinal headache, are possible. Currently, the
superior technique and best drugs to administer are unclear.
In contrast, rom limited data, intravenous sedation or nitrous
oxide does not appear to improve ECV success (Burgos, 2016;
Dochez, 2019; Khaw, 2015; Straube, 2021).
■ Moxibustion
Tis is a traditional Chinese medicine technique that burns a
cigarette-shaped stick o ground Artemisia vulgaris—which is
also known as mugwort or in Japanese as moxa. At the BL 67
acupuncture point, the stick is directly placed against the skin
or indirectly heats an acupuncture needle at the site to increase
etal movement and promote spontaneous breech version
(Ewies, 2002). It is perormed usually between 33 and 36 weeks’
gestation to permit a trial o ECV i not successul. Results
rom randomized controlled studies are conicting (Bue, 2016;
Coulon, 2014; Coyle, 2012; Sananes, 2016; Vas, 2013).
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