Abnormal Labor - William Obstetric 24th Study Guide

23–1.

Which of the following may be responsible for dystocia in labor?

a.

Bony-pelvis abnormalities

b.

Inadequate expulsive forces

c.

Soft-tissue abnormalities of the reproductive tract

d.

All of the above

23–2.

Which of the following is true regarding cephalopelvic disproportion?

a.

It currently is responsible for 34% of dystocia cases.

b.

It is a term that originated in the 1960s to describe abnormal bony pelves.

c.

It was defined during a time when dystocia

developed secondary to vitamin D deficiency or rickets, which is now rare in developed countries.

d.

B and C

23–3.

In this diagram below, what represents the biggest obstacle to labor and delivery?

a.

Prominent coccyx

b.

Contraction band in the lower uterine segment

c.

Decreased anteroposterior diameter of the pelvic inlet

d.

A and C C.R . C. R . A B Ac tive Pa s sive Int. os In t. o s Ext. o s Ex t. o s

Reproduced with permission from Cunningham FG, Leveno KJ, Bloom SL, et al (eds): Abnormal labor. In Williams Obstetrics, 24th ed. New York, McGraw-Hill, 2014, Figure 23-1. C. R. = contraction ring, Ext. = external, Int. = internal.

Abnorma l La bor CH A P T E R 2 3

151 23–4.

The National Institute of Child Health and Human Development (NICHD) and American College

of Obstetricians and Gynecologists (ACOG) have made recommendations concerning the diagnosis of arrested second-stage labor. Which of the

following statements are consistent with their recommendations?

a.

Arrested labor in the second stage should not be diagnosed until adequate time has elapsed.

b.

Before this diagnosis is given, nulliparas without epidural anesthesia should be allowed 2 hours without progress.

c.

Before this diagnosis is given, nulliparas without epidural anesthesia should be allowed 3 hours without progress.

d.

A and C

23–5.

At Parkland Hospital, neonates delivered from parturients whose second-stage labor lasted > 3 hours had which of the following adverse outcomes compared with neonates of mothers with shorter second-stage labor?

a.

Neonates from each group of parturients had equivalent rates of perinatal morbidity.

b.

The lowest prevalence of 5-minute Apgar scores ≤ 3 was noted in the group of parturients with longer second-stage labor.

c.

The percentage of neonates requiring resuscitative efforts was higher in the group of parturients with longer second-stage labor.

d.

B and C

23–6.

Which of the following is among the advances in labor dysfunction management?

a.

Use of oxytocin

b.

Reliance on midforceps deliveries for transverse arrest

c.

Realization that undue prolongation of labor leads to increased perinatal morbidity

d.

A and C

23–7.

Where are contraction forces the greatest during normal labor?

a.

Fundus

b.

Lower uterine segment

c.

Midzone of the posterior uterine wall

d.

Forces are equal throughout the uterus

23–8.

The Montevideo group concluded that which of the following was the lowest contraction pressure necessary to cause cervical dilation?

a.

15 mm Hg

b.

25 mm Hg

c.

35 mm Hg

d.

45 mm Hg

23–9.

Terms to describe specific active-phase abnormalities include which of the following?

a.

Arrest disorders

b.

Saltatory disorders

c.

Protraction disorders

La bor SE C T I O N 7

152 23–10.

What is the total number of Montevideo units shown in this monitor strip?

a.

235

b.

242

c.

196

d.

None of the above

23–15.

Which of the following is true regarding chorioamnionitis and its effects on labor?

a.

Infection in early labor is a cause of labor dysfunction.

b.

Infection in late second-stage labor is a by-product of dysfunctional labor.

c.

Chorioamnionitis is most often associated with precipitous labor.

d.

A and C

23–16.

For low-risk parturients, walking in the first stage of labor has which of the following effects?

a.

Has no effect on labor length

b.

Decreases second-stage labor length

c.

Decreases the neonatal 5-minute Apgar score

d.

Increases the length of the latent phase of labor

23–17.

Compared with recumbent positioning, upright positions during second-stage labor are associated with which of the following?

a.

Less pain

b.

Slightly shorter labor duration

c.

Higher rates of blood loss exceeding 500 mL

d.

All of the above

23–11.

According to data from Menticoglou (1995a,b), approximately what percentage of parturients achieved spontaneous vaginal delivery in the

subsequent hour once second-stage labor reached 5 hours?

a.

0.5%

b.

c.

15%

d.

20%

23–12.

Which of the following is true regarding coached maternal pushing efforts during second-stage labor?

a.

It has no effect on second-stage length.

b.

It significantly shortens the second stage.

c.

It shortens the second stage but has no effect on maternal or neonatal morbidity rates.

d.

B and C

23–13.

In laboring nulliparas, fetal station above 0 is associated with which of the following?

a.

A 25% cesarean rate

b.

A 50% cesarean rate

c.

A higher cesarean rate than if the head is engaged

d.

A and C 30 60 90 180 150 120 210 30 60 90 180 150 120 210 30 60 90 180 150 120 210 10 min FHR 240 bpm FHR 240 bpm FHR 240 bpm 100 0 25 50 75 100 0 25 50 75 100 0 25 50 75 mmHg _UA _mmHg 49 mm Hg 44 mm Hg 47 mm Hg 50 mm Hg 52 mm Hg mmHg UA UA mmHg 2 1 3 ₄ ₅

Reproduced with permission from Cunningham FG, Leveno KJ, Bloom SL, et al (eds): Abnormal labor. In Williams Obstetrics, 24th ed. New York, McGraw-Hill, 2014, Figure 23-3.

23–14.

Which of the following is true regarding epidural anesthesia during labor?

a.

It slows the first stage of labor.

b.

It slows the second stage of labor.

c.

It has no effect on the length of labor.

d.

A and B

Abnorma l La bor CH A P T E R 2 3

153 23–18.

Laboring in a birthing tub is associated with higher rates of which adverse neonatal outcome?

a.

Waterborne infection

b.

Neonatal hypocalcemia

c.

Neonatal intensive care admission

d.

A and C

23–19.

According to research by Hannah (1996) and Peleg (1999), which of the following is true regarding premature rupture of membranes at term?

a.

Cesarean delivery rates were lowest in those managed expectantly.

b.

Oxytocin induction led to the lowest rates of chorioamnionitis.

c.

Prophylactic antibiotics significantly lowered rates of chorioamnionitis.

d.

A and C

23–20.

Which of the following is true regarding precipitous labor?

a.

Defined as delivery within 3 hours of labor onset

b.

May result from diminished pelvic soft-tissue resistance

c.

May result from a decreased sensation and awareness of active labor

d.

All of the above

23–21.

Which of the following is an associated complication of precipitous labor and delivery?

a.

Uterine atony

b.

Chorioamnionitis

c.

Shoulder dystocia

d.

A and B

23–22.

In obstetrics, which of the following defines a contracted pelvic inlet?

a.

A transverse diameter < 12 cm

b.

A diagonal conjugate < 11.5 cm

c.

An anteroposterior diameter < 10 cm

d.

All of the above

23–23.

The computed tomographic image shown here demonstrates which of the following?

Reproduced with permission from Cunningham FG, Leveno KJ, Bloom SL, et al (eds): Abnormal labor. In Williams Obstetrics, 24th ed. New York, McGraw-Hill, 2014, Figure 23-4C.

a.

Obstetrical conjugate

b.

Intertuberous diameter

c.

Transverse diameter of the midpelvis

d.

Transverse diameter of the pelvic inlet

23–24.

Which interischial tuberous diameter measurement serves as the threshold to define pelvic outlet

contraction?

a.

7 cm

b.

8 cm

c.

9 cm

d.

10 cm

23–25.

Your patient has a history of a prior pelvic fracture. Which of the following is true regarding this

condition?

a.

Most cases are caused by a fall.

b.

It is a contraindication to vaginal delivery.

c.

Bony anatomy must be reviewed with pelvimetry prior to allowing vaginal delivery.

La bor SE C T I O N 7

154 23–26.

The graphic below demonstrates the prevalence of cesarean deliveries after a failed forceps delivery attempt plotted against fetal birthweight. Which of the following is true regarding these data?

25 20 15 Pe r ce nt Birthwe ight 10 5 0 2500–27992800–30993100–3399 3400–3699370 0–3999 4000–43994300–45994600–4899

Reproduced with permission from Cunningham FG, Leveno KJ, Bloom SL, et al (eds): Abnormal labor. In Williams Obstetrics, 24th ed. New York, McGraw-Hill, 2014, Figure 23-5.

a.

Most cesarean deliveries occurred in women with macrosomic babies.

b.

Fetal size appears to be the significant contributor to failed forceps deliveries.

c.

Nearly 20% of cesarean deliveries occurred in women whose newborns weighed < 3100 g.

d.

None of the above

23–27.

This image illustrates which fetal presentation?

Reproduced with permission from Cunningham FG, Leveno KJ, Bloom SL, et al (eds): Abnormal labor. In Williams Obstetrics, 24th ed. New York, McGraw-Hill, 2014, Figure 23-6.

a.

Brow presentation

b.

Face presentation

c.

Occiput presentation

d.

Synciput presentation

23–28.

Which of the following is a risk factor for face presentation?

a.

Prematurity

b.

Multiparity

c.

Anencephaly

d.

All of the above

Abnorma l La bor CH A P T E R 2 3

155 23–29.

This image illustrates which fetal presentation?

Reproduced with permission from Cunningham FG, Leveno KJ, Bloom SL, et al (eds): Abnormal labor. In Williams Obstetrics, 24th ed. New York, McGraw-Hill, 2014, Figure 23-8.

a.

Brow presentation

b.

Face presentation

c.

Occiput presentation

d.

Synciput presentation

23–30.

This vigorous newborn most likely presented how during labor?

a.

Brow presentation

b.

Face presentation

c.

Occiput presentation

La bor SE C T I O N 7

156 23–31.

Which of the following describes the position of the fetus in this drawing?

Reproduced with permission from Cunningham FG, Leveno KJ, Bloom SL, et al (eds): Abnormal labor. In Williams Obstetrics, 24th ed. New York, McGraw-Hill, 2014, Figure 23-9C.

a.

Left acromidorsoanterior

b.

Left acromidorsoposterior

c.

Right acromidorsoanterior

d.

Right acromidorsoposterior

23–32.

Common causes of transverse lie include which of the following?

a.

Nulliparity

b.

Prolonged labor

c.

Placenta previa

d.

Oligohydramnios

23–33.

Which of the following complications may follow vaginal delivery with the presentation shown here?

Reproduced with permission from Cunningham FG, Leveno KJ, Bloom SL, et al (eds): Abnormal labor. In Williams Obstetrics, 24th ed. New York, McGraw-Hill, 2014, Figure 23-11.

a.

Klumpke palsy

b.

Cookie-cutter scalp laceration

c.

Significant brachial plexus injury

d.

Ischemic necrosis of the presenting forearm

23–34.

The following adverse outcomes are associated with dystocia?

a.

Chorioamnionitis

b.

Retained placenta

c.

Puerperal endometritis

d.

A and C

23–35.

In which of the following clinical scenarios is prolonged labor associated with uterine rupture?

a.

High parity

b.

Previous cesarean delivery

c.

32-week fetus in a transverse lie

d.

All of the above

23–36.

Prolonged labor can result in which of the following maternal complications?

a.

Uterine rupture

b.

Fistula formation

c.

Symphyseal necrosis

d.

A and B MCGH319-CH23_150-158.indd 156 6/13/14 2:41 PM

Abnorma l La bor CH A P T E R 2 3

157 23–37.

Which of the following nerves is more commonly injured during vaginal delivery due to poor patient positioning?

a.

Femoral nerve

b.

Ilioinguinal nerve

c.

Genitofemoral nerve

d.

Common fibular nerve (formerly common peroneal nerve)

References

Hannah M, Ohlsson A, Farine D, et al: International Term PROM Trial: a RCT of induction of labor for prelabor rupture of membranes at term. Am J Obstet Gynecol 174:303, 1996

Menticoglou SM, Manning F, Harman C, et al: Perinatal outcomes in relation to second-stage duration. Am J Obstet Gynecol 173:906, 1995a

Menticoglou SM, Perlman M, Manning FA: High cervical spinal cord injury in neonates delivered with forceps: report of 15 cases. Obstet Gynecol 86:589, 1995b

Peleg D, Hannah ME, Hodnett ED, et al: Predictors of cesarean delivery after prelabor rupture of membranes at term. Obstet Gynecol 93:1031, 1999