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Delivery: Complicated Vaginal
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Deliveries andSurgical
Interventions
SarahWhite, SamanthaShirk, andBrianBrost
4
Take-Home Points
• Fetal malpresentation, such as persistent
occiput posterior or occiput transverse presentations, is associated with increased maternal
and neonatal complications, including prolonged labor, increased rates of third- and
fourth-degree perineal lacerations, postpartum
hemorrhage, chorioamnionitis, and operative
deliveries.
• While rates of operative vaginal deliveries are
declining, they remain an important skill set in
modern obstetrics.
• Operative vaginal delivery is associated with
an increased risk of levator ani injury with
forceps-assisted vaginal delivery having a
much stronger association with injury compared to vacuum-assisted delivery. This is
S. White
Section on Maternal-Fetal Medicine, Department of
Obstetrics and Gynecology, Wake Forest School of
Medicine, Winston-Salem, NC, USA
e-mail: sewhite@wakehealth.edu
S. Shirk
Division of Maternal Fetal Medicine, Department of
Obstetrics and Gynecology, TriHealth, Cincinatti,
OH, USA
B. Brost (*)
Division of Maternal Fetal Medicine, Department of
Obstetrics and Gynecology, University of Kansas
School of Medicine, Kansas City, KS, USA
e-mail: bbrost@kumc.edu
thought to be due to numerous factors including rapid descent of fetal head, increased
space requirements needed to place the device,
and increased traction pressures.
• Routine episiotomy is not recommended due
to lack of evidence demonstrating maternal or
fetal benet. Complications of episiotomy
include third- or fourth-degree perineal laceration, bleeding, infection, breakdown of the
episiotomy, postpartum pain, and
dyspareunia.
• Median episiotomy is associated with an
increased risk of anal sphincter injury, whereas
mediolateral episiotomy may be protective
against sphincter injury.
• Cesarean section now accounts for approximately 21% of deliveries globally.
• Studies have been unable to identify an optimal manner in which to close hysterotomy.
While two-layer hysterotomy closure is generally recommended, studies have not shown a
clear benet to this technique. A preferred
suture material has also not been identied.
• Pelvic oor changes are identied postpartum
following both vaginal deliveries and cesarean
sections.
• Postpartum tubal ligation is normally performed via the Parkland, Pomeroy, or modied Pomeroy methods.
© Springer Nature Switzerland AG 2023
M. Gomes-Ferreira, J. Olivas-Menayo (eds.), Post-maternity Body Changes,
https://doi.org/10.1007/978-3-030-43840-1_4
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4.1 Introduction
Labor is dened in the Merriam-Webster dictionary as the process of childbirth, especially the
period from the start of uterine contractions to
delivery. As presented in the previous chapter,
there are specic anatomical and physiological
changes of pregnancy and childbirth that allow for
the normal process of labor. However, there are
instances when these processes do not occur cohesively resulting in protraction of labor. During
these times, operative or surgical means may be
necessary to effect delivery. In this chapter, we discuss some etiologies of dysfunctional labor and
management options to effect delivery along with
the long-lasting anatomic and physiologic effects
of these management options. Additionally, we
discuss the potential anatomic and physiologic
effects of permanent female sterilization.
4.2 Vaginal Delivery withFetal
Malposition
Vaginal delivery is most common when cephalic
fetuses are both vertex and occiput anterior
position. Fetal position describes the presenting
fetal part relative to the maternal pelvis. In the
setting of a vertex presentation, the fetal occiput
is used to describe the fetal position, and a
cephalic fetus in the occiput transverse or
occiput posterior position is considered to have
fetal malposition. Malpositioning of the fetus is
associated with higher rates of perinatal complications, most commonly cesarean delivery.
Persistent occiput posterior position (OP) is
the most common malposition at delivery with an
incidence ranging between 2 and 13% [1–3]. In
approximately 20% of laborers, the fetus enters
the pelvis in an OP position. The right OP position is slightly more common than the left. It also
appears from radiographic evidence that the OP
position is more often associated with a narrow
anterior pelvis or android pelvis [4].
Fetal malposition with OP position has been
associated with both increased maternal and neonatal complications. There are a number of studies that have observed that the OP position is
associated with prolonged labor, increased rates
of third-degree or fourth-degree perineal lacerations, postpartum hemorrhage, chorioamnionitis,
and operative deliveries, including both operative
vaginal delivery and cesarean delivery [5, 6].
Cheng and colleagues compared outcomes of
2591 women with persistent occiput position to
those of 28,801 women with occiput anterior
position presentations. Data from this study
found that essentially every possible delivery
complication was more frequent with a persistent
OP position. Additionally, only 46% of these
women delivered spontaneously [5]. To date,
there is no known effective intervention to minimize OP position prior to labor [7]. The nursing
and midwifery literature has described a variety
of maternal positions during labor to facilitate
resolution of OP position, but, to date, none of
these maternal positions have been examined in
prospective, randomized controlled trials [8].
Early in labor, it is common for the vertexpresenting fetus to be in occiput transverse (OT)
position. However, with internal rotation, a standard cardinal movement of labor, the majority of
fetuses present with occiput anterior position
during the active phase of the rst stage of labor
or the second stage of labor.
Numerous studies have studied the prevalence
of OT position and found that 19–49% are in OT
position at the onset of labor [9, 10], 10–20% are
in OT position in the second stage of labor [10–
12], and 3–8% are in OT position at delivery [9,
13]. In one study by Lieberman etal., the operative
delivery rate was 87% when OT position was present at birth compared with 24% when the fetus
was in occiput anterior position [9]. Furthermore,
the occiput transverse position is associated with
more frequent augmentation of labor, need for episiotomy, higher order perineal lacerations, febrile
morbidity, prolonged second stage of labor, and
low 5-min APGAR scores [14].
4.2.1 Manual Rotation
As previously mentioned, fetal malposition is
associated with labor dystocia, increased cesarean
delivery, and operative vaginal delivery, as well as
higher risk of maternal and neonatal morbidity.
Manual rotation of the fetal occiput from occiput
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posterior or occiput transverse to occiput anterior
was rst described as a potential interventional
maneuver for malposition in 1971 by Walkowiak
[15]. Manual rotation prior to the second stage of
labor is not recommended as the fetal head can
rotate on its own during the rst stage of labor
[16]. Recent studies support manual rotation as a
safe and effective intervention in the setting of
labor arrest, particularly in the second stage. A
high rate of successful rotation ranging between
74 and 93% among those who underwent a trial of
rotation was observed in these studies [17, 18].
Compared with expectant management, women
whose fetuses underwent successful rotation to
occiput anterior position were less likely to require
delivery by cesarean or operative vaginal deliveries. Outcome data on morbidity and mortality
associated with manual rotation is scarce.
However, maternal risks of manual rotation,
namely, cervical laceration, are minimal when the
procedure is performed by a skilled practitioner
after completion of the rst stage of labor [16].
4.2.2 Face Presentation
With this presentation, the fetal head is hyperextended so that the occiput is in contact with the
fetal back and the mentum (chin) is presenting
(Fig. 4.1). The fetal face may present with the
mentum anterior or posterior relative to the
maternal symphysis. The incidence of face presentation reported by Cruikshank and White was
0.17% [19].
Fig. 4.1 Face presentation
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S. White et al.
Causes of face presentation are numerous and
include any condition that favors fetal head
extension or prevents fetal head exion. Preterm
infants with their smaller head dimensions [16]
and fetal malformations such as anencephalic
fetuses [20] oftentimes prevent the necessary cardinal movement of head exion. Additionally,
hyperextended positions develop more frequently
when the maternal pelvis is contracted or the
fetus is very large [21].
Many mentum posterior presentations convert
spontaneously to anterior [22]; however, if this
does not occur, this fetal malpresentation precludes the necessary fetal head exion required
to negotiate the birth canal. In term fetuses, face
presentations are more common in women with
some degree of pelvic inlet contraction and routinely require cesarean delivery to effect delivery.
Persistent mentum posterior presentation prevents a successful vaginal delivery, and attempts
to convert a face presentation with manual or forceps rotation into an alternative fetal presentation
are dangerous and should not be done.
4.2.3 Brow Presentation
Brow presentation is a rare presentation that is
diagnosed when the portion of the fetal head
between the orbital ridge and the anterior fontanel presents at the pelvic inlet (Fig.4.2). Except
when the fetal head is small or the pelvis is
unusually large, engagement of the fetal head and
subsequent delivery cannot take place as long as
the brow presentation persists.
The etiologies of brow presentation are the
same as face presentation. According to the study
performed by Cruikshank and White, brow presentation is commonly unstable and converts to
either normal occiput presentation or face presentation [19]. Principles of management are the
same as those for a face presentation.
4.3 Operative Deliveries
Operative vaginal delivery, in which the second
stage of labor is shortened with the use of either
forceps or a vacuum device, is an important technique employed when delivery needs to be expedited. Such situations include fetal distress,
maternal comorbidities necessitating a shortened
second stage, or maternal exhaustion, and operative delivery offers an alternative method to
cesarean section. While the use of forceps was
rst described in the 1600s and has been used for
centuries, current trends demonstrate a decrease
in use. The reported rates of operative vaginal
delivery range from 3 to 5% [23, 24] and are
decreasing as the rate of cesarean sections
increases. Merriam etal. demonstrated a decrease
in vacuum-assisted deliveries from 5.8 to 4.1%
between 2005 and 2013 and a decrease in forcepsassisted deliveries from 1.4 to 0.9%. Regional
trends have also been noted with higher rates in
the Midwest and South, while the lowest rates are
noted in the Northeast [24]. Despite the decreased
use and the maternal and fetal risks associated
with operative delivery, many women will choose
operative delivery to avoid the longer recovery
and long-term sequelae of a cesarean section.
Thus, operative delivery remains an important
skill set in obstetrics.
Fig. 4.2 Brow presentation
4.3.1 Forceps-Assisted Vaginal
Delivery
Forceps were rst described in the 1600s but
became more widely used following modication of the device in the 1750s to include a pelvic
curve. However, as cesarean sections have
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become safer to perform, and following the introduction of the vacuum device, the rate of forceps-
in which the fetal head is not yet at +2 but is
engaged in the maternal pelvis.
assisted deliveries has declined. In 1990, the rate
of forceps deliveries was 5.11%, whereas by
2017, the rate had fallen to 0.5% [25].
4.3.2 Types ofForceps (Table4.1)
Forceps deliveries were reclassied in 1988
into three types by the American College of
Obstetricians and Gynecologists: outlet, low, and
midforceps. High forceps deliveries, in which the
fetal head is not yet engaged, are no longer performed in modern obstetrics. An outlet forceps
delivery is one in which the scalp is visible at the
introitus, the fetal skull has reached the pelvic
4.3.2.1 Simpson
Simpson forceps were introduced in 1848 and are
the most commonly used type of obstetric forceps (Fig.4.3). These forceps are characterized
by an elongated cephalic curve to allow to use
with a molded fetal head most commonly seen in
a nulliparous patient.
oor, the fetal head is at or on the perineum and
in right or left occiput anterior or posterior position, and rotation is less than 45°. A low forceps
delivery is one in which the leading point of the
fetal skull is at +2 or more but not yet reaching
the pelvic oor, and there is no restriction on
rotational degrees. A midforceps delivery is one
Table 4.1 Types of forceps
Forceps Description Indication Advantages Disadvantages
Simpson Fenestrated blade with
TuckerMcLane
Kielland Slight pelvic curve;
Barton Anterior hinged blade;
Piper Long shank with
Spatula Two independent levers
elongated cephalic
curve; parallel shank;
Luikart modication of
blade available
Smooth blade;
overlapping shank
overlapping shank;
sliding lock
posterior blade with
deep cephalic curve;
sliding lock
backward curve; no
pelvic curve
that do not articulate;
smooth blade
Molded hold Can be used in nulliparous
Unmolded head;
rotation
Rotational
maneuvers
Deep transverse
arrest in
platypelloid
pelvis
Delivery of
after-coming
head in breech
deliveries
Delivery of fetal
head
4.3.2.2 Tucker-McLane
Tucker-McLane forceps were introduced in 1868
and have a smooth blade without fenestrations
(Fig.4.4). These forceps are used when deliver-
ing a non-molded fetal head most commonly
seen in a multiparous patient.
Risk of neonatal injury
females and in fetuses with
caput
Can be used in multiparous
females or those with rapid
cervical dilation/minimal
molding; overlapping shanks
cause less perineal stretching
Can be used for rotational
maneuvers
Can be used for deep
transverse arrest
Long shanks and lack of
pelvic curve allow direct
application to after-coming
head
Decreased risk of neonatal
cerebral hemorrhage
or facial nerve palsy;
risk of maternal perineal
laceration
Risk of neonatal injury
or facial nerve palsy;
risk of maternal perineal
laceration
Due to minimal pelvic
curve, more likely to
cause sulcal tears once
fetal head is at the level
of pelvic oor
Limited use outside of
deep transverse arrest
Limited use outside
breech deliveries
Limited use outside of
Europe; possible
increased risk of
lacerations
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Fig. 4.3 Simpson forceps
4.3.2.3 Kielland
Kielland forceps were rst introduced in 1915 by
Dr. Christian Kielland. These blades have a slight
pelvic curve with an overlapping shank and a
sliding lock (Fig.4.5). Due to the minimal pelvic
curve, these forceps are used to correct rotational
defects.
4.3.2.4 Barton
Barton forceps were introduced in 1925 to aid in
the delivery of fetuses with deep transverse arrest
in a platypelloid pelvis (Fig. 4.6). In this situation, the Kielland forceps cannot be used as the
fetus must be delivered in the OT position, and
the anterior blade of the Kielland forceps could
damage the symphysis or the bladder. The Barton
forceps have an anterior hinged blade, a posterior
blade with a deep cephalic curve, and shanks
Fig. 4.4 Tucker-McLane forceps
attached to anterior and posterior blades at a 50°
angle to form a pelvic curve when held with the
shanks perpendicular to the horizontal.
4.3.2.5 Piper
Piper forceps were introduced in 1924 to aid in
the delivery of the after-coming head in vaginal
breech deliveries (Fig.4.7). Piper forceps have
long shanks with a backward curve, which drops
the handles below the level of the blades.
Additionally, there is no pelvic curve allowing
for application to a fetal head at high station.
4.3.2.6 Spatula
The Thierry and Teissier spatulas consist of two
independent and symmetric branches, which
include a shank, handle, and wide solid blade.
Teissier spatulas are shorter and preferred for
preterm deliveries. The shanks do not articulate
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Fig. 4.5 Kielland rotational forceps
preventing compression of fetal head between the
blades, leading to the main advantage of spatulas,
to lower the risk of cerebral hemorrhage and cranial injury.
4.3.2.7 Vacuum
Vacuum-assisted vaginal delivery was rst
described in 1705 by Yonge with the use of a
glass cup vacuum device. Multiple iterations of
vacuum devices have been described including
an air tractor vacuum described by Simpson in
1848 and a metal cup vacuum device by Malstrom
in 1953. Currently, bell-shaped and hemispheric
vacuum devices are used. The past 20years have
seen an increase in vacuum-assisted vaginal
deliveries, and 5% of vaginal deliveries in the
United States are now assisted via vacuum
devices. The indications and contraindications
for use of vacuum are the same as those for forceps. While forceps are thought to cause more
maternal morbidity, vacuum devices are thought
Fig. 4.6 Barton forceps
to cause more neonatal morbidity. A metaanalysis of ten clinical trials demonstrated a
lower risk of severe perineal laceration with the
vacuum as compared to forceps. However, the
same study demonstrated a high rate of scalp
injury and cephalohematoma with vacuum as
compared to forceps [26].
There are two main types of vacuum devices:
a soft cup and a rigid cup. Soft cups are pliable
and funnel or bell shaped, whereas rigid cups are
mushroom shaped and rm. The cups are attached
to a pliable or freely rotating stem to prevent the
torque of the cup and subsequent scalp injury. A
meta-analysis of 1375 women demonstrated that
soft cups are more likely to fail due to detachment as compared to rigid cups, but they are less
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Fig. 4.7 Piper forceps
likely to cause fetal scalp injury. In addition,
there was no increased risk of perineal trauma
[26]. Other studies have not shown increased failure rates when using soft cups. It is generally recommended to use a soft cup for straightforward
vacuum extractions and rigid cups for occipitoposterior presentation, signicant caput succedaneum, larger infants, or asynclitism.
In order to effect a successful vacuum-assisted
delivery, the vacuum device must be placed symmetrically over the sagittal suture approximately
2cm anterior to the posterior fontanelle. Vacuum
pressure is then applied to create a chignon, and
with each contraction, vacuum pressure is
2
increased to 0.8kg/cm
. There is no difference in
neonatal outcomes if the pressure is maintained
or reduced between contractions. The traction
force needed to ensure a vaginal delivery is
unknown. However, an observational study of
119 deliveries demonstrated that a pressure of
450 mmHg was adequate for delivery in most
cases, and all patients were delivered with pres-
S. White et al.
sures of 500–600mmHg [26]. Higher pressures
are associated with increased risk of neonatal
injury.
4.4 Pelvic Floor Following
Operative Delivery
The use of forceps to effect vaginal delivery is a
known risk factor for the development of pelvic
oor dysfunction. In his meta-analysis, Friedman
etal. described an odds ratio of 6.94 for levator
ani avulsion when comparing forceps-assisted
vaginal delivery to spontaneous vaginal delivery.
The odds ratio for avulsion when comparing forceps-assisted vaginal delivery to vacuum- assisted
vaginal delivery was 4.57, placing a patient who
has undergone a forceps-assisted vaginal delivery
at highest risk for pelvic oor dysfunction in the
future. In a longitudinal study of women
16–24years following vaginal delivery, women
who had a forceps delivery were more likely to
have stage 2 prolapse or have undergone surgery
for prolapse compared to those who had spontaneous vaginal deliveries or vacuum- assisted
deliveries. Hiatal area was also larger in women
who had undergone forceps delivery [27].
Vacuum-assisted delivery, like forcepsassisted vaginal delivery, is associated with an
increased risk of levator ani injury, though it is
thought to be a weak risk factor. In a large metaanalysis, Friedman et al. found an OR 1.27 for
vacuum-assisted delivery compared to a spontaneous vaginal delivery [27]. This risk may be due
to rapid descent of the fetal head associated with
the use of vacuum devices, increased space
requirements needed to place the device, and
increased traction pressures. Similarly, GarciaMejido demonstrated an increased risk of levator
ani injury with an avulsion rate of 34.2% compared to 9.6% in spontaneous vaginal deliveries
[28]. When rigid and soft cups were compared to
determine the risk of levator ani injury as seen on
3D sonography at 6months postpartum, no difference in risk was discovered. In this study, levator ani muscle avulsion was seen in 33% of
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