Module 6: The First Stage of Labor (1-22 Guided Questions)

Question 1

List the components of an admission history and physical and appropriate admission lab tests when a woman is in labor.

Answer 1

*Personal information, past obstetric history, past medical and primary healthcare history, and family history should be reviewed.
*Present pregnancy history should be reviewed to confirm gestational age and estimated date of delivery, significant prenatal events, and presence of a personalized plan for birth.
*P/E
*Pelvic/Cervical Exam
*Labs

Question 2

Describe the component “pregnancy history” of an admission history and physical and appropriate admission lab tests when a woman is in labor.

Answer 2

o Age Parity
o Estimated date of delivery and estimated weeks of gestational age
o Complications of current pregnancy, including group B Streptococcus status
o Major complications of previous pregnancies, including prenatal, intrapartum, and postpartum periods
o Previous labor experience, including duration
o Mode of previous births/deliveries
o Size of previous babies Fetal movement pattern Vaginal bleeding
o Status of membranes
o Time of onset of contractions, and character of contractions from onset to the present, including frequency, duration, intensity, and aggravating and relieving factors
o Last oral intake

Question 3

Describe the component “P/E” of an admission history and physical and appropriate admission lab tests when a woman is in labor.

Answer 3

o Vital signs: blood pressure, temperature, pulse, respirations
o Auscultation of heart and lungs
o Abdominal palpation to determine contraction pattern and fetal lie, presentation, position, and engagement
o Abdominal palpation to determine estimated fetal weight and fundal height
o Visual inspection for abdominal scars
o Assessment for presence of peripheral or facial edema

Question 4

Describe the component “pelvic/cervical exam” of an admission history and physical and appropriate admission lab tests when a woman is in labor.

Answer 4

o Cervical effacement and dilatation
o Position of the cervix
o Station of fetal presenting part
o Presence of molding or caput succedaneum
o Fetal lie, presentation, and position
o Tone and elasticity of vagina and length of perineum
o Confirmation of membrane status
o Visual inspection of perineum
o Assessment of fetal heart rate

Question 5

Describe the component “labs” of an admission history and physical and appropriate admission lab tests when a woman is in labor.

Answer 5

o Available prenatal records can be reviewed to identify the woman’s blood type and Rh status, anemias, glucose tolerance testing, and specific perinatal infections including GBS carrier status, hepatitis B infection or carrier status, and HIV status.
 Complete blood count (CBC)
 Blood type, Rh status, and antibody screen
 Urinalysis
o In the case of a woman presenting with no prenatal record, all routine prenatal laboratory tests will be obtained to provide a baseline for development of a management plan.

Question 6

Know the recommended frequency for the assessment of maternal vital signs in the first stage of labor.

Answer 6

• The following schedule for checking vital signs is frequently encountered as policy for a woman (without epidural anesthesia) during the first stage of labor who does not have a specific condition that would require more frequent monitoring:
  o Blood pressure, pulse, and respirations: every hour
  o Temperature: every 2 to 4 hours when the temperature is normal and the membranes are intact, and
   every 1 to 2 hours if the temperature is abnormal and/or after the membranes have ruptured.

Question 7

Know the recommended frequency for the assessment of maternal bladder/urine in the first stage of labor.

Answer 7

o A distended bladder can impede the progress of labor by preventing fetal descent as well as increasing the discomfort and pain in the lower abdomen that women frequently experience during labor.
o A woman in labor should be encouraged to empty her bladder at least every 2 hours during the active phase of the first stage of labor.
o This provides an opportunity for the clinician to evaluate maternal hydration status.
o Presence of ketones or protein in the urine may be helpful in developing the management plan and can be assessed as indicated.

Question 8

Evaluate maternal well-being based on vital signs

Answer 8

As a woman’s status may change over the course of her labor, the frequency of assessing vital signs should be adjusted to match her unique situation

Question 9

Review the recommendations for the frequency of fetal heart rate assessment during labor.

Answer 9

*CEFM:
o No complications: First stage q30/Second stage q15
o Complications: First stage q15/Second stage q5

*IA:
o ACOG: First stage q15/Second stage q5
o ACNM: First stage q15-30/Second stage no pushing q15/Second stage pushing q5
o AWHONN: Active phase of First stage q15-30/Active pushing of Second stage q5-15

Question 10

Understand maternal adaptations in labor of the cardiovascular system and apply to labor management

Answer 10

o Increased blood volume by about 40% in early third trimester  increased CO and SV
o Increased RBC production (Maximize oxygen delivery to mom & baby)
o Significant shifts in blood volume during contractions

Question 11

Understand maternal adaptations in labor of the hematologic system and apply to labor management

Answer 11

o Levels of coagulation factors are markedly increased during active labor
 Promote rapid hemostasis after placental separation.

o Clot development leads to reduced circulating fibrinogen and platelets ->decreased fibrolytic activity
 Enhances clot development after delivery of placenta.

o Uterine contraction and compression of uterine vessels serve to promote accumulation of clotting factors and hemostasis after placental separation 
 Reduces risk of excessive maternal blood loss.

o Peak WBCs during labor (as high as 20,000)
Not accurate to determine presence of infection in labor.

Question 12

Understand maternal adaptations in labor of the respiratory and system and apply to labor management

Answer 12

o Increased O2 consumption as muscular activity increases during uterine contractions.
o Failure to restore oxygenation to uterine muscle cells (during relaxation) over time can lead to anaerobic metabolism, production of lactic acid, and subsequent ischemic pain that is theorized to contribute to uterine pain felt during labor.
o Pain can lead to increased respiratory rate and hyperventilation  respiratory alkalosis
 pain management, PRN O2

Question 13

Understand maternal adaptations in labor of the gastrointestinal system and apply to labor management

Answer 13

o Decreased gastric motility, relaxation of gastroesophageal sphincter, increased intraabdominal pressure  increased risk for emesis & aspiration if laboring woman is sedated or intubated
o Transient nausea/vomiting may occur during active labor, especially during transition.
 Antiemetics PRN
o Consider nutritional needs during labor – hypoglycemia due to fasting leads to use of alternative metabolic pathways  accumulation of byproducts like lactate & ketones
 Intake of isotonic sports drinks and a light diet

Question 14

Apply criteria for normal and slow labor progress to clinical situations. (Review module 4 content)

Answer 14

• 0.5 cm per hour or
• 0.5-0.7/0.5-1.3 cm per hour (nullips/multips, with faster dilation as labor progresses)
• Longer labors are not associated with an increase in any complications.
• Although a longer second stage was not shown to result in increased perinatal complications, the research did consistently show an increase in cesarean birth, operative vaginal birth, and third- and fourth-degree lacerations.
• Some researchers argue that the problem with longer second stages is the tendency for providers to intervene with treatments that are the cause for higher rates of maternal morbidity.

Question 15

Review recommendations for the appropriate use of vaginal exams during the first stage of labor.

Answer 15

During normal first-stage labor, a cervical examination may be indicated in the following situations:
o To establish an informational baseline that can be used for appropriately timing further examinations to establish labor status prior to admission or labor interventions (prelabor, latent, or active labor).
o As an appropriately timed second examination to determine the woman’s labor state prior to labor admission (prelabor, latent, or active labor).
o To inform management decisions related to management of labor pain.
o To verify complete dilation.
o To check for a prolapsed cord after spontaneous rupture of membranes if a prolapsed cord is a suspected risk (e.g., ballottable presenting part or fetal heart rate decelerations that do not resolve with usual maneuvers).

Question 16

Be familiar with the history of the policy of withholding foods and oral fluids during labor.

Answer 16

*Contemporary management of labor in the United States typically involves limited oral nutritive intake and noncaloric intravenous fluid administration.
o The primary rationale cited for withholding food and fluid during labor is the decreased risk of gastric content aspiration during general anesthetic induction—an extremely rare but serious syndrome first described by Mendelson in 1946.
o Moreover, fasting does not guarantee an empty stomach or less acidity.

Question 17

Understand current evidence regarding encouraging or withholding foods or oral fluids during labor and apply it in clinical situations.

Answer 17

• Overall, modern evidence shows no benefits or harms associated with oral intake during labor, so there is no justification for the restriction of fluids and food in labor for women at low risk for complications.
• Adequate hydration during labor would seemingly assist in the delivery of oxygen and nutrients as well as facilitate the elimination of waste from the contracting uterus, akin to how proper hydration benefits the skeletal muscle of athletes.

Question 18

List indications for IV access and/or IV fluids.

Answer 18

*The decision to initiate and maintain intravenous access during labor should be based on actual or potential risk factors for each woman.
o Women who cannot tolerate oral fluid intake may require intravenous fluids.
o Intravenous access is also necessary for administration of some medications, such as antibiotic prophylaxis for women who are carriers of GBS, pain medications, or oxytocin augmentation.
o Prior to initiation of epidural anesthesia, establishing intravenous access allows for administration of isotonic fluid blood volume expanders to mitigate epidural-related hypotension.
 Continuing access after epidural placement allows for ongoing fluid administration and medication administration should complications develop.

Question 19

Understand the significance of ketonuria to the laboring woman.

Answer 19

• Inadequate caloric intake leads to breakdown of stored fat instead of glucose for energy. Ketones are a byproduct of fat breakdown. Helps assess current nutrition status and promote nutrition interventions as needed.
• Ketones can remain in the urine after serum ketones have been cleared, and this finding may lead to unnecessary intervention.
• In a Cochrane review, the authors concluded that there is no information on which to base practice regarding treatment of women with ketosis during labor.
• Management decisions are further complicated by a high false-positive rate in methods to test for ketonuria (eg, Ketostix/Multistix).

Question 20

Know the potential hazards to the newborn of giving dextrose containing intravenous hydration to a laboring woman. This information can be found in the ACNM Clinical Bulletin “Providing Oral Nutrition to Women in Labor” at the end of the section called “The effects of fasting during labor.”

Answer 20

In large doses, intravenous dextrose caused fetal lactic acidosis, newborn jaundice and hypoglycemia.

Question 21

Know the disadvantages of a supine maternal position during labor.

Answer 21

• Increased duration of labor, risk of caesarean birth, and the need for epidural, and may be associated with increased intervention and negative effects on mothers’ and babies’ well-being. Increased likelihood of NICU admissions.
• When resting in bed is necessary or desired, lateral recumbent positions are preferred to supine positions because they reduce the potential for aortic/venae cavae compression with resulting maternal hypotension and potential fetal compromise. Lateral positions also facilitate kidney function and do not interfere with coordination and efficiency of uterine contractions.

Question 22

Know the impact of maternal position on:

Answer 22

• In the supine position contractions are more frequent and painful, yet less likely to improve labor progress!

Question 23

Know the impact of squatting and “hands and knees” positions on pelvic dimensions.

Answer 23

• In both squatting and hand-to-knee (leaning forward while kneeling) positions, the sagittal outlet and interspinous diameter were significantly greater than when women were supine.
• In addition, squatting increased the intertuberous diameter and decreased the obstetric conjugate diameter.

Question 24

List different positions and movements for labor and indicate their proposed benefit. Please note that you are not required to memorize exactly what part of the pelvis moves in which direction with each position or movement. This information is included to provide you with a repertoire of position suggestions for women in a wide variety of situations.

Answer 24

• Side lying positions
• Sitting positions
• Sitting upright
• Kneeling positions
• Squatting positions
• Supine positions
• Semisitting and side lying positions are restful and gravity neutral. They may help an exhausted woman save her energy, especially if she has been up and walking for a long period. Also, if progress is rapid, neutralizing gravity may slow the labor to a more manageable pace.
• Upright positions take advantage of gravity to apply the presenting part to the cervix, improve the quality of the contractions, and enhance the descent of the fetus.
• Positions in which the woman leans forward are thought to enhance fetal rotation or help maintain the favorable occiput anterior (OA) position and reduce back pain.
• Asymmetrical positions, in which the woman flexes one hip and knee, change the shape of the pelvis, enhance rotation, and reduce back pain.
• The exaggerated lithotomy position, used for several contractions in the second stage, may facilitate the passage of a “stuck baby” beneath the pubic symphysis.
• Dorsal positions tend to cause supine hypotension and increase back pain. Contractions are more frequent and painful, yet less likely to improve labor progress!

Question 25

Discuss assessment and management strategies for a fetus suspected or known to be a posterior position.

Answer 25

• Do not try to put the baby into an occiput anterior position before labor.
• Teach and encourage women and staff the movements, positions, and techniques to use in labor that change gravity influences and pelvic shape.
• Provide space for laboring women to move and equipment to aid with positions and movement.

Question 26

Discuss assessment and management strategies for a laboring mother with back pain

Answer 26

o Do not assume that the fetus is occiput posterior; many causes for back pain are possible.
o Confirm with ultrasound examination or another reliable method.
o Without ultrasound confirmation, consider other causes of back pain, and with trial and error, use measures listed next.
o Treat the woman’s pain
 Nonpharmacologically: continuous labor support, walking, abdominal lifting, ice, heat, massage and pressure, bath or shower, hands and knees and other forward leaning positions, TENS, and sterile water injections.
 Pharmacologically: provide epidural or systemic medications if requested.

Question 27

Discuss management of a stalled labor with or without back pain.

Answer 27

o Provide continuous labor support and encouragement
o Assume fetal malposition and confirm position of baby with ultrasound or another reliable method.
o Treat nonpharmacologically and noninvasively, using ultrasound findings of fetal position to plan the direction of asymmetrical positions and movements and assess the success of these measures.
 Lunging
 Abdominal stroking
 Kneeling on one knee
 Side lying
 Semi-prone positions
o If not using ultrasound,
 Try all positions and movements.
 Use trial and error with the asymmetrical actions.
 Emphasizing those that feel better to the woman.
 Look for improved progress in dilation or descent.
o Rotate the fetal head digitally or manually
o If these measures are not successful, use obstetric interventions.

Question 28

What are the indications for amniotomy?

Answer 28

o Treatment of dystocia
o Adjunct intervention for women who have a clear indication for induction of labor
o When internal monitoring is required.

Question 29

What are the contraindications for amniotomy?

Answer 29

o Unengaged presenting part
o Any contraindication to vaginal birth
o Known or suspected vasa previa

Question 30

Describe the process of amniotomy.

Answer 30

o Before performing AROM, the midwife carefully reassesses the fetal station and ensures the fetal head is well applied to the cervix.
o Keeping the fingers in the cervix, the membranes can be gently disrupted with the Amniohook.
o Care should be taken to avoid scratching the fetal head and the clinician’s fingers should be left in place during the initial gush of fluid to ensure a prolapsed cord does not occur.
o The fetal heart rate should be assessed during the procedure and monitored frequently for a short time afterward.

Question 31

Know the risks and benefits of routine amniotomy including the effect on the perception of pain, labor duration, fetal and neonatal status, and rates of analgesia use and cesarean birth. Please note the following:1) Read the information on routine amniotomy and cesarean birth in the Cochrane review carefully, specifically in the discussion section. If you only read the author’s conclusions you will miss the information on this issue. 2)The Greulich and Tarrant article on the latent phase from module 5 makes reference to a now outdated Cochrane review on amniotomy. The 2013 Cochrane review on the topic is current.)

Answer 31

*Length of Labor
o Subgroup analysis of primiparous women only showed a statistically significant reduction in the length of the second stage of labor in the amniotomy group.
o Subgroup analysis of multiparous women only showed that there was NO statistically significant reduction in the length of the second stage of labor in the amniotomy group.

*Fetal/Neonatal Status
o In first stage labor, women in the amniotomy group had an increased risk of a suboptimal or abnormal fetal heart trace; however, the difference was not statistically significant. There was no statistically significant difference between the two groups in the risk of suboptimal or abnormal fetal heart trace in the second stage of labor.
o In the primiparous subgroup, babies born to women who were randomized to the control group showed a statistically significant increase in the chance of an Apgar score of less than seven at five minutes. In the multiparous subgroup, there was no difference between the amniotomy group and control group.
o There was no statistically significant difference between the two groups in the risk of admission to a neonatal intensive care or special care nursery

*Pain
o There was no statistically significant difference between the two groups in the use of pain relief.
o If already experiencing intense pain, may not be a good idea.

• CS
  o Women in the amniotomy group had an increased risk of delivery by caesarean section compared with women in the control group though not SS.
  o There was no statistically significant difference between the two groups in the incidence of caesarean section for fetal distress.
  o Discussion- The results show a trend towards an increase in the risk of a caesarean section which neared significance, in women who have had an amniotomy. It cannot be stated that there is no difference between the two groups on the basis that this finding nears statistical significance, and there are clinically significant implications and consequences of having a caesarean section.
  o It should be noted that the indication for caesarean section was often unclear in the trial reports.
  o There is a possibility that the method of fetal heart monitoring in labor may be a confounding variable affecting the indication for caesarean section, over and above whether a woman received an amniotomy or not.
   In a recent Cochrane review looking at continuous cardiotocography (CTG) in labor, there was a significant increase in caesarean sections associated with continuous cardiotocography.

Question 32

Know the following about the use of hydrotherapy (also called water immersion during labor: use of analgesia, reported maternal pain, labor duration, operative delivery, and neonatal outcomes

Answer 32

• Bathing provides buoyancy and warmth, both of which often bring immediate pain relief, relaxation, lowering of catecholamines, increase in oxytocin, lowering of elevated blood pressure, and more rapid active labor progress.
• Entrance into the water before 5 cm dilation, however, has been associated with longer labor and greater need for oxytocin augmentation.
• A recent meta-analysis of randomized controlled trials found significant reductions in both epidural use and reported pain in the women who used a bath during labor. There were no differences in operative deliveries, Apgar scores below 7 at 5 minutes, admissions to neonatal intensive care units, or neonatal infection rates.
• A randomized controlled trial found that when dystocia has been diagnosed, bathing significantly decreases the need for labor augmentation with amniotomy and oxytocin.

Question 33

Know the impact of continuous support during labor on the use of analgesia, cesarean birth, operative vaginal delivery, and maternal satisfaction.

Answer 33

• Fewer CS
• Less oxytocin use
• Less pain medication use
• Increased birth experience satisfaction
• Cochrane Review
  o “Meaningful benefits and no known harm.”
• The women who benefited most were those whose care was provided by doulas rather than by nurses, whose support was begun during early rather than in active labor, and those who were not accompanied by a loved one rather than those who were accompanied by a loved one.

Question 34

Apply basic principles of labor support as discussed in the recorded lecture.

Answer 34

• Emotional support
  o Physical presence
  o Encouragement
  o Reassurance
  o Providing sense of security

*Tangible assistance
o Direct care
o Comfort measures

• Knowledge support
  o Explanation
  o Advice
  o Information giving
• Bag of Tricks
  o Rhythmic breathing
  o Vocalizations
  o Positions/movement
  o Heat/cold
  o Warm water immersion
  o Touch
  o Physical presence
  o Environment

Question 35

Discuss the data on the effectiveness of the following techniques for reducing pain and increasing comfort in labor: Intracutaneous/intradermal sterile water injections (also known as sterile water papules)

Answer 35

o The mechanism of action is not fully understood but appears to be linked to the Gate Control Theory of pain relief. More specifically, it appears that the sterile water acts as a mild irritant stimulating localized discomfort.
o The subcutaneous injections were found to be as effective as intracutaneous injections in relieving back pain and significantly less painful during administration.
 A more recent study confirmed this finding Therefore, experts now recommend giving subcutaneous sterile water injections rather than intradermal injections for back pain relief in labor.

o Hutton and colleagues conducted a meta-analysis of sterile water injections that included eight randomized controlled trials. They found that women who received the sterile water injections had a significant reduction in cesarean birth.

Question 36

Discuss the data on the effectiveness of the following techniques for reducing pain and increasing comfort in labor: Acupuncture

Answer 36

o Acupuncture appears to stimulate the release of beta endorphins (endogenous analgesics).
o There also appears to be an additional relaxation effect when acupuncture is used during labor.
o No risks from acupuncture have been identified when it is practiced by trained practitioners using disposable needles.

Question 37

Discuss the data on the effectiveness of the following techniques for reducing pain and increasing comfort in labor: TENS

Answer 37

o Overall, there was no significant difference between TENS and control groups in pain ratings, although the two trials of TENS applied to acupuncture points indicated reduction in severe pain.
 Some studies reported lower use of added pain medications in the TENS groups than in the control groups.
 No adverse events were reported.
 Despite the lack of objective evidence of pain reduction with the most common applications of TENS, the majority of women using it were satisfied and stated they would use it again in a future labor.

Question 38

Discuss the data on the effectiveness of the following techniques for reducing pain and increasing comfort in labor: Touch and massage

Answer 38

o Two trials of massage by women’s partners, who were taught to give 20-to-30-minute massages to the women several times during labor, found that the massage groups had less pain and anxiety and reported greater satisfaction with their childbirths than the control groups.
o Another trial used a pain questionnaire to compare labor pain in one group of laboring women who received usual nursing care plus massages at three times in the first stage of labor, with a similar group who received usual care only.
 The massage group reported less pain up to 7 cm of dilation, at which time pain was assessed as the same in the two groups.

Question 39

Discuss the data on the effectiveness of the following techniques for reducing pain and increasing comfort in labor: Application of Heat and Cold

Answer 39

o One recent study found that alternating heat and cold on the low back and lower abdomen during the first stage and on the perineum during the second stage reduced women’s labor pain as assessed with a Visual Analogue Scale.

Question 40

Review the information in Varney’s Midwifery on the use of inhaled analgesics (nitrous oxide) for pain relief in labor, noting the information on the effectiveness and maternal and fetal side effects.

Answer 40

• Nitrous oxide is a weak anesthetic when used in high doses and has analgesic and anxiolytic effects at low doses.
• N2O/O2 can be used as the sole analgesic, or it can be administered in combination with opioids or opioid agonist–antagonists.
• It is self-administered by the woman via a handheld facemask over her nose and mouth or via a mouthpiece.
  o Self-administration is not only empowering for the woman, but also acts as a safety mechanism because it is almost impossible to overdose with N2O/O2 when it is self-administered.
• Potential side effects of N2O/O2 include nausea in 5% to 40% of women and vomiting in as many as 15%, dizziness, and dysphoria, although the occurrence of these side effects is rare.
• No fetal heart rate abnormalities have been attributed to its use, and this agent does not affect uterine contractility. The half-life in the neonate is approximately 3 minutes, and no neonatal adverse outcomes have been found following maternal use during labor.
• Adverse effects on the fetus or newborn have not been seen in the extensive history of this agent as a labor analgesic, although some theoretical risks are associated with higher doses than those used for labor analgesia that have not been well studied.