ISSUES IN MODE OF DELIVERY
| ELECTIVE CESAREAN DELIVERY: THE WAVE OF THE FUTURE ?—Lawrence D. Devoe, MD, Professor, Maternal-
Fetal Medicine, Department of Obstetrics and Gynecology, Medical College of Georgia, Augusta
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| Introduction: increased demand for elective cesarean delivery over last several decades; coinciding trends—decreased
family size; increased electronic fetal monitoring (EFM; independent risk factor for cesarean delivery); increased use of
antibiotics; decreased experience in operative vaginal delivery (OVD) and breech delivery; fewer registered nurses to
support laboring patients; factors contributing to cesarean delivery rate—regional variations; hospital volume and
status; practitioner features and practice style; litigation; maternal characteristics; practice issues and shortcomings—
EFM interpretation; OVD; management of labor; vaginal birth after cesarean delivery (VBAC) utilization; societal issues
(expectation of “perfect” baby); indications for cesarean delivery—performing first cesarean delivery drives increase
in overall rate; multiple factors contribute to increase; nulliparas and multiparas account for two-thirds of all
cesarean deliveries; increased cesarean delivery not correlated with better perinatal outcomes in lower risk patients
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| American College of Obstetricians and Gynecologists (ACOG) task force on cesarean delivery rates:
laudable undertaking, but resulted in little impact on current practice; increase in primary cesarean delivery parallels total
cesarean delivery rate, which cannot be explained by decreasing use of VBAC; cesarean delivery on demand estimated to
account for 4% to 18% of cesarean deliveries; origins of cesarean delivery on request—Feldman and Freiman (1985)
proposed concept of “prophylactic cesarean delivery at term,” in which risk for maternal death weighed against number of
neonates saved; questioned whether patient should be offered cesarean delivery as option
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| National Institutes of Health (NIH) consensus meeting 2005: questions asked to assess evidence supporting
cesarean delivery—what are risks and benefits for mother and infant? what evidence supports physician–patient dialogue?
what questions not currently answered? what additional data needed? accepted indications for elective cesarean
delivery—breech presentation; estimated fetal weight >4500 g if mother diabetic (>5000 g if mother nondiabetic); single
previous cesarean delivery
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| Maternal considerations: benefits—protection of pelvic floor; reduced incontinence; reduced pelvic organ prolapse;
avoidance of risks from emergency cesarean delivery; proximate risks—death, anesthetic complications, infection,
hemorrhage, visceral injury, thromboembolism, and rehospitalization; remote risks—death in subsequent pregnancies
(eg, uterine rupture); placenta previa and accreta; adhesion formation and sequelae
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| Fetal considerations: proximate risks—pulmonary problems; fetal injuries (lacerations); effects of maternal hypotension;
interference with maternal-infant bonding; benefits—reduction in antepartum stillbirths, meconium aspiration, maternal
transmission of infectious disease to neonate, intracranial (IC) hemorrhage, and birth trauma
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| NIH conference statement: issues addressed—trends and incidence of cesarean delivery; short-term or long-term
benefits of cesarean delivery to mother and infant, compared to benefits of planned vaginal birth; factors that influence
benefit and harm; areas for future research; maternal outcomes with moderate evidence—postpartum hemorrhage (favors
planned cesarean delivery); length of hospital stay (favors vaginal delivery); maternal outcomes with weak
evidence—reduction in infection (favors planned vaginal delivery); avoiding anesthetic complications (favors planned
vaginal delivery; excludes emergency cesarean delivery); subsequent placenta previa (doubled by cesarean delivery);
breast-feeding (no difference in first year); urinary incontinence; surgical and traumatic complications; subsequent uterine
rupture; hysterectomy; subsequent fertility
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| Pelvic floor dysfunction: observations—weaker pelvic floor muscles after vaginal birth than after planned cesarean
delivery; many older women experience uterine prolapse or urinary or anal incontinence, regardless of delivery mode;
non sequiturs—vaginal birth causes pelvic floor weakness; planned cesarean delivery protects all or most patients;
evidence supports—many patients have stress urinary incontinence (SUI) during pregnancy; episiotomy weakens
floor muscles, compared to no episiotomy or perineal tear; instrumental delivery increases risk
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 | Endoanal findings: one study showed ≈90% of symptomatic women had sphincter defects 6 wk postpartum; Sultan
showed 32% of patients with sphincter defects had symptoms, and no patients who had cesarean delivery had sphincter
defects; Rieger showed sphincter defects in 41% of vaginal deliveries, and no sphincter defects in women delivering by
cesarean; multivariate analysis showed episiotomy and OVD dominant risk factors for sphincter laceration; Peleg et al
reported ≈20% of primiparas had third- or fourth-degree lacerations, and 8% of those patients had third- or fourth-degree
lacerations in subsequent vaginal delivery; with episiotomy and OVD in second vaginal delivery, 12% of women
had recurrence; speaker offers elective cesarean delivery for patient who has had previous anal sphincter rupture; parameters
apparent shortly after delivery may mitigate with time; Lal et al reported pregnancy (not mode of delivery)
may be cause of anal incontinence
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| SUI: data show no difference in SUI before, during, or after pregnancy; SUI not necessarily prevented by cesarean delivery;
current literature does not support cesarean delivery to prevent pelvic floor dysfunction; weak evidence not favoring
either delivery route—pelvic organ prolapse; sexual function (limited data); subsequent stillbirth higher in next
pregnancy after cesarean delivery
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| Neonatal harm: iatrogenic prematurity—studies show doubling of respiratory distress and neonatal intensive care
unit (NICU) admissions for neonates delivered by elective cesarean delivery for each week <39 wk; fetal mortality—
favors cesarean delivery (if <40 wk); neonatal IC hemorrhage—favors cesarean delivery; birth injury (brachial
plexus injury and lacerations)—fewer with cesarean delivery; neonatal infection—less with cesarean delivery; neonatal
death—evidence lacking to support cesarean delivery; cesarean delivery and neonatal pulmonary status—data
show cesarean delivery independent risk factor for respiratory distress syndrome (3-fold increase); reduced if cesarean
delivery follows labor; Towner (1999) showed risk for death, IC hemorrhage and other complications reduced significantly
with elective cesarean delivery (study had no control for disease states or indications for intervention); speaker
concludes adverse outcomes not completely avoided by cesarean delivery, and number of neonates in study with adverse
outcomes extremely small
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| Other factors to consider: patient-specific—age, parity, obesity, estimated gestational age, and psychologic factors;
cost of cesarean delivery on request—if vaginal birth without oxytocin (Pitocin) or epidural, ≈15% to 20% savings;
savings nullified by oxytocin, increased by 10% with epidural; failed vaginal delivery exceeded cost of elective cesarean
delivery by 8%; cost/benefit issue unresolved; ethical issues—autonomy and beneficence
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| Evidence-based review of cesarean delivery on request (Visco et al 2006): maternal risks if first cesarean
delivery—maternal mortality (no difference); infection (lower, unless overall rates compared); need for anesthesia
(higher); hemorrhage/transfusion (lower); venous thromboembolism (no difference); hysterectomy (no difference); surgical
complications (lower than planned); potential breast-feeding issues (no difference); postpartum pain (no difference);
postpartum depression (no difference); maternal length of stay (longer than with vaginal delivery); urinary incontinence
(lower [controversial]); anorectal function (lower than with unplanned cesarean delivery or instrument delivery); pelvic
organ dysfunction (no evidence); sexual function (no difference); subsequent cesarean delivery—fertility issues
(higher risks not specific to cesarean delivery on maternal request); subsequent uterine rupture (higher in patients who attempt
labor than in patients who have elective repeat cesarean delivery); subsequent placenta previa (higher, and increases
with each cesarean delivery); subsequent stillbirth (high with cesarean delivery, but not specific to cesarean
delivery on maternal request [unexplained finding]); fetal risk—fetal mortality (no evidence showing improvement);
neonatal mortality (higher risk for cesarean delivery [unadjusted data]); respiratory morbidity (higher for cesarean delivery);
neonatal asphyxia/hypoxic-ischemic encephalopathy (data inconsistent); IC hemorrhage (no difference between
spontaneous vaginal delivery and planned cesarean delivery); brachial plexus injury (lower for elective cesarean delivery);
neonatal length of stay (longer for selective cesarean delivery); long-term outcomes (no evidence)
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| Summary: planned cesarean delivery—increases risk for anesthesia and risk of abnormal placentation with subsequent
pregnancy; may decrease risk for urinary incontinence and anorectal dysfunction; fetal risk —brachial plexus injury and
IC hemorrhage unpredictable, but rare; IC hemorrhage multifactorial and rare; term cerebral palsy rarely due to intrapartum
events; respiratory morbidity increased; many elective cesarean deliveries required to avoid one bad outcome; future
research needs—surveys of patients, providers, institutions, and insurers; tracking codes to identify cesarean delivery
on request; prediction and influence of likelihood of vaginal delivery and reduction of maternal-infant complications (ie,
who is going to have successful uneventful labor and who is not); prospective multicenter multidisciplinary studies with
long-term follow-up; accumulation of large databases to assess risk for rare outcomes
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| Conclusions: demand for elective cesarean delivery increasing; insufficient evidence to evaluate risks and benefits; individualized
decision consistent with ethics; not recommended if several children desired; should not be performed at <39
wk of gestation or without verification of fetal lung maturity; should not be motivated by lack of effective pain management
resources
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| OPERATIVE VAGINAL DELIVERY: EVIDENCE AND INSIGHTS —Michael A. Belfort, MD, PhD, Professor of Obstetrics
and Gynecology, Division of Maternal–Fetal Medicine, University of Utah School of Medicine, Salt Lake City
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| Common areas of liability: poor assessment of case (“rush in and do delivery”); lack of basic knowledge about anatomy
and definitions; failure to prepare for cesarean delivery in event that operative delivery fails; lack of appropriate discussion
and consent; lack of appropriate documentation (or late documentation); failure to examine patient after repair;
failure to disclose or follow up on complication
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| Definitions: engagement— when widest diameter of presenting part (usually biparietal diameter) at or below plane of
maternal pelvic inlet; best determined by combination of abdominal and vaginal assessment; station—relationship between
leading bony part of fetal presenting part (skull bone, not scalp) and maternal ischial spines; failing to take into
account caput succedaneum and severe molding in cases of cephalopelvic disproportion common error; do not perform
OVD when severe caput succedaneum prevents accurate diagnosis of station or head position; station—reclassified in
1989; new classification defines station in terms of level of leading bony point of fetal head in centimeters (thirds previously
used) at or below level of maternal ischial spines; important everyone involved in delivery use same definition;
fetal head diameters/parietal eminence—usually 5 to 6 cm from top of head; widest portion of neonate’s head in vertex
presentation; suboccipitobregmatic—vertex occipitoanterior (OA) head position; 9.5 cm (less than biparietal diameter);
not widest diameter of presentation; occipitofrontal—widest diameter in occipitoposterior position, 11.5 cm;
proceeds down more slowly; greater failure of OVD and more maternal damage; mentovertical—brow presentation;
14 cm; submentobregmatic—9.5 cm face presentation; some face presentations deliver vaginally; degrees of
molding—no molding if able to get finger into suture and move bones around; 1+—bones touching, but moveable;
2+—bones overlap, but can be separated; 3+—bones overlapping and inseparable; degrees apply to parietal bones,
not occipital bones (occiput slips underneath parietal bone); be familiar with types of delivery, eg, outlet, low, midforceps
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| Documentation: critical to prepare preoperative note describing indications for procedure, type of delivery anticipated,
and data supporting decision; obtain patient consent and document that cesarean delivery offered as alternative if appropriate;
checklist (eg, station, fetal, and maternal considerations) recommended before beginning OVD; study of 100 appropriate
consecutive OVDs showed 61% had only general consent form, and only 3% had documentation about specific
maternal risks; none documented discussion of neonatal risks; 22% documented cesarean delivery discussed as alternative
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| Abdominal examination: helps to confirm fetal lie, presentation, and often position; may provide some reference to
position of fetal back in relation to uterine midline; allows assessment of fetal weight and amount of fetal head above pelvic
brim; is fetal head engaged?—3 finger breadths (only with OA position), head not engaged; head engaged with 2,
1, or no fingers; basovertical diameter—from base of skull to most distant point of vertex; molding can give false impression
of engagement because basovertical diameter lengthened; lowest part of skull and scalp descends below spines,
but base of skull may still be high and unengaged; Philpott’s rule of 3s (1982)—“in OA presentation, if the sum of the
number of fifths of the fetal head palpated above the pelvic inlet abdominally, and the degree of molding of the fetal head
palpated vaginally, equals or exceeds three, then attempted operative vaginal delivery is likely to be unsuccessful and
should be avoided”
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| Sequential OVD: no longer acceptable; using multiple instruments, failing with OVD attempt, >3 pulls with OVD attempt,
and >3 hr of pushing all lead to significant increases in neonatal IC hemorrhage and seizures, facial nerve and brachial
plexus lesions, neonatal trauma, NICU admission, and maternal trauma; Towner et al showed 1 in 334 failed
vacuum extraction/forceps procedures followed by cesarean delivery had IC hemorrhage, compared to 1 in 860 for vacuum
extraction and 1 in 664 for forceps procedure (incidence not significantly different from a cesarean delivery after
failed labor)
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| Vacuum extraction: posterior edge of vacuum cup should be midline in front of posterior fossa and anterior edge, ≈3
cm behind anterior fontanelle (document as flexing median application); nonflexion point application results in more frequent
pop-offs, increased subgaleal hemorrhage, more frequent lacerations and abrasions, and higher failure rates;
pulls—package insert for Kiwi forceps instructs 1 or 2 pulls for outlet delivery, 2 or 3 pulls for low forceps delivery, and
3 or 4 pulls for midpelvic delivery; with first pull, expect to see flexion of head; with second pull, head on pelvic floor;
with third pull, delivery of head; do not reapply vacuum after second pop-off (similar recommendations as for Mityvac);
between pop-offs, reexamine position and station and inspect scalp for trauma; pull not well defined; speaker defines as
traction efforts during single contraction; only those traction efforts with obvious strain; standards need to be developed
for reposition with leaking, relaxing during maternal breath, or slight direction changes; failed OVD—significantly increased
maternal trauma (odds ratio 4.1); >3 pulls with OVD instrument lead to significantly increased neonatal trauma,
regardless of whether completed or failed; increased NICU admission with failed OVD with >3 pulls; VacuLink—
provides tracing of what occurred during time of vacuum cup application; may be helpful medicolegally; federal law requires
compliance with manufacturers’ recommendations when using vacuum extractors and requires every adverse outcome
associated with vacuum extraction to be reported to Food and Drug Administration
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Suggested Reading
Bettes BA et al: Cesarean delivery on maternal request: obstetrician-gynecologists’ knowledge, perception, and practice
patterns. Obstet Gynecol 109:57, 2007; Feldman GB, Freiman JA: Prophylactic cesarean section at term? N Engl J
Med 312:1264, 1985; Lal M et al: Does cesarean delivery prevent anal incontinence? Obstet Gynecol 101:305, 2003;
Murphy DJ et al: Early maternal and neonatal morbidity associated with operative delivery in second stage of labour: a
cohort study. Lancet 358:1203, 2001; National Institutes of Health State-of-the Science Conference Statement:
Cesarean delivery on maternal request. Obstet Gynecol 107:1386, 2006; Peleg D et al: Risk of repetition of a severe
perineal laceration. Obstet Gynecol 93:1021, 1999; Richter HE: Cesarean delivery on maternal request versus
planned vaginal delivery: impact on development of pelvic organ prolapse. Semin Perinatol 30:272, 2006; Towner D et
al: Effect of mode of delivery in nulliparous women on neonatal intracranial injury. N Engl J Med 341:1709, 1999;
Philpott RH: The recognition of cephalopelvic disproportion. Clin Obstet Gynaecol 9:609, 1982; Visco AG et al:
Cesarean delivery on maternal request: maternal and neonatal outcomes. Obstet Gynecol 108:1517, 2006; Wax JR: Maternal
request cesarean versus planned spontaneous vaginal delivery: maternal morbidity and short term outcomes. Semin
Perinatol 30:247, 2006.
Educational Objectives
| The goal of this program is to improve surgical practice in elective cesarean delivery and operative vaginal delivery.
After hearing and assimilating this program, the clinician will be better able to:
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| 1. Recognize factors contributing to the current cesarean delivery rates.
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| 2. Discuss maternal and fetal risks and benefits associated with cesarean delivery.
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| 3. Assess the National Institute of Medicine’s statement on cesarean delivery on maternal request.
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| 4. Recognize areas of increased medical liability when performing operative vaginal delivery.
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| 5. Identify practices associated with operative vaginal delivery that increase the chance of an adverse outcome.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty members to disclose relevant
financial relationships within the past 12 months that might create any personal conflicts of interest. Any identified
conflicts were resolved to ensure that this educational activity promotes quality in health care and not a proprietary business
or commercial interest. For this program, the following has been disclosed: Dr. Devoe is a consultant to Neoventa Medical
and Phillips Medical.
Acknowledgements
Dr. Devoe was recorded at Clinical Approaches to Obstetrics and Gynecology, sponsored by the Medical College of
Georgia, and held June 29 to July 1, 2007, in Savannah, GA. Dr. Belfort was recorded at Antepartum and Intrapartum
Management, sponsored by the University of California, San Francisco, School of Medicine, and held June 7-9, 2007, in
San Francisco, CA.
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