Labor and Delivery: Part 1

Labor and Delivery: Part 1

Instructor: Megan Stevens DNP, RN, NPD-BC, IBCLC
Learning Outcomes

  1. Discuss signs and symptoms of impending labor.

  2. Distinguish between true and false labor.

  3. Explain the seven factors that affect the labor process.

  4. Identify the stages of labor.

  5. Describe the assessment for labor and delivery.

  6. Discuss nursing interventions related to labor and delivery.

  7. Outline medical interventions related to labor and delivery.

Topics in Part 1

  • Normal Labor

  • 7 Ps of Labor and Delivery

  • Maternal systemic responses to labor

  • Stages of Labor

Understanding Labor
Definition of Labor

Labor is a physiological process during which the fetus, umbilical cord, placenta, and amniotic membranes are expelled from the uterus. This process is accomplished through uterine contractions, accompanied by cervical effacement (thinning) and dilation (opening). Labor typically begins between 38 weeks and 42 weeks of gestation.

Onset of Normal Labor

Theories of Labor Onset

  1. Hormonal Factors
       - Hormones involved:
         - Oxytocin: Stimulates uterine contractions.
         - Prostaglandins: Promote cervical ripening.
         - Declining progesterone levels: Reduces inhibition of uterine activity.
         - Increasing estriol: Produced from fetal cortisol.

  2. Mechanical Stretching:
        - Physical stretching of the uterus and cervix may help trigger labor.

Signs of Impending Labor

  • Lightening: Approaches 2 weeks before labor begins, often with the fetus “dropping” into the pelvis.

  • Braxton-Hicks contractions: Irregular, intermittent contractions that may occur in the second trimester and become more noticeable.

  • Burst of energy: Often referred to as a “nesting” instinct.

  • Increased vaginal mucus discharge and bloody show: Indicates cervical changes.

  • Reduced fetal activity: Fetus seems less active as it positions for labor.

  • Spontaneous Rupture of Membranes (SROM): Often called “water breaking,” this involves a large gush or small trickle of amniotic fluid, which should be clear and not malodorous.

Braxton-Hicks Contractions

  • Occur as mild, intermittent, irregular abdominal contractions beginning in the second trimester.

  • These are known as false labor as they do not cause cervical changes.

  • May disappear or decrease with activity.

  • Interval between contractions does not shorten.

True vs. False Labor

True Labor:

  • Contractions are regular, become closer together, stronger, and longer in duration.

  • Begin in the lower back and move to the lower abdomen.

  • Contractions do not stop with rest.

  • Cervical changes occur: softening, effacement, and dilation.

  • Fetus continues its descent into the pelvis.

False Labor:

  • Irregular contractions that do not follow a pattern.

  • Variable length and intensity, typically most noticeable in the fundus.

  • Stop with relaxation or rest; there is no effacement or dilation, and no change in fetal position.

7 P’s of Labor and Delivery

  1. Passageway: Refers to the pelvis and soft tissues.

  2. Passengers: The fetus and placenta.

  3. Powers: Contractions that propel the fetus.

  4. Position of Mother: Any position (standing, walking, side-lying, etc.) during labor.

  5. Psyche: Psychological response of the mother.

  6. Pain: Acknowledgement of pain involved in labor.

  7. Patience: The need for patience throughout the labor process.

Details of Each P

Passageway

  • Pelvis directs the fetus into the true pelvis, which is divided into three segments.

  • Dimension and capability must be assessed to ensure the baby can fit through the pelvis without complications such as cephalopelvic disproportion.

Soft Tissues

  • Uterine tissues are thicker at the upper end and thinner at the lower end.

  • Downward pressure from contractions results in cervical effacement and dilation.

  • Vagina can stretch, and its mucosa thickens in preparation for delivery.

  • Loosening of connective tissues and perineal stretching occurs.

Fetal Considerations

Fetal Skull

  • The fetal skull is typically the largest part of the body.

  • The bones are not fused, allowing for molding (overlapping of bones) as they pass through the pelvis.

  • Important landmarks:
      - Sutures: Where bones meet.
      - Fontanelles: Areas where sutures intersect; can be palpated with a dilated cervix.

Fetal Attitude

  • Refers to the relationship of fetal body parts to one another; the ideal attitude is flexion.

Fetal Lie

  • Describes the relationship of the fetus's spine to the mother’s spine; ideally should be longitudinal.

Fetal Presentation

  • The part of the fetus closest to the cervix:
      - Cephalic (96%): Vertex (top of head-first), brow, face, mentum (chin).
      - Breech (3%): Includes Complete breech, Frank breech, and Footling breech.
      - Shoulder or Other (1%).

Fetal Position

  • The relationship of the fetus presenting part to the sides of the mother’s pelvis:
      - Mother’s right vs left, anterior vs posterior.
      - Occiput (O), Breech (S), Shoulder (SC).

  • Most common fetal positions include LOA (Left Occipitoanterior) and ROA (Right Occipitoanterior).

  • Determined by ultrasound and fetal heart tones.

Fetal Station

  • Defined as the level of the presenting part of the fetus in relation to an imaginary line between ischial spines (zero station) in the midpelvis of the mother.

Monitoring Fetal Status

  • Fetal Heart Rate (FHR) must be monitored:
      - First Stage: Every 15-30 minutes.
      - Second Stage: Every 5 minutes.
      - Post SROM: Immediately after rupture of membranes.

  • Normal FHR range: 110-160 bpm.

  • A decrease in FHR by more than 30 bpm indicates fetal distress and must be reported immediately.

Passenger: The Placenta

  • Third Stage of Labor:
      - Uterine contractions decrease the size of the attachment site, leading to separation from the uterus starting 5-7 minutes after birth and typically lasting 15-30 minutes.

Powers

Definition of Powers

  • Primary Powers (involuntary contractions): Forces that help expel the fetus.

  • Secondary Powers (voluntary pushing): Efforts made by the mother to aid in delivery.

Primary Powers Characteristics

  • Phases of Contractions:
      - Increment: Build-up phase of the contraction.
      - Acme/peak: The height or peak intensity of the contraction.
      - Decrement: The relaxation phase following the contraction.

Characteristics of Contractions

  1. Frequency: Time in minutes from the beginning of one contraction to the beginning of the next.
       - Report frequency if less than 2 minutes apart.

  2. Duration: Time in seconds from the beginning to the end of a contraction.
       - Report duration if greater than 90 seconds due to risk of uterine rupture.

  3. Intensity: Strength at its peak.
       - Classified subjectively (mother’s description) and objectively (palpation).
       - Palpation classifications:
         - Feels like the tip of the nose (mild), chin (moderate), forehead (strong).
       - Electronic intrauterine pressure catheter (IUPC) can also be used to measure.

Results of Primary Powers

  • Cervical effacement: Expressed in percentage (%).

  • Dilation of cervix: Expressed in centimeters (cm).
       - Ranges from 1 cm to 10 cm.

  • Descent of fetus: Expressed in cm above (minus) and below (plus) the ischial spines.

  • Primary powers may be affected by interventions such as narcotics or epidural analgesia, leading to less frequent and intense contractions.

Effacement

  • Definition: Thinning, shortening, and obliteration of the cervix during labor.
      - 0% Effaced: No change in cervix.
      - 30% Effaced: Partial effacement.
      - 100% Effaced: Complete effacement (the cervix is thinned out).

Cervical Dilation

  • Visualization guide of cervical dilation measures:
      - 1 cm: Cheerio®   - 3 cm: Slice of Banana
      - 4 cm: Cracker
      - 7 cm: Bagel
      - 10 cm: Fully dilated.

Secondary Powers

  • Definition: Voluntary bearing down efforts made by the mother when the presenting part reaches the pelvic floor.

  • This involuntary urge to push leads to contraction of the diaphragm and abdominal muscles, increasing intra-abdominal pressure and compressing the uterus.

  • It is critical to wait until the cervix is fully dilated to minimize the risk of swelling and tearing, achieving maximum effect during the urge to push.

Positioning During Labor

  • The mother should find the most comfortable position: upright, squatting, kneeling, or side-lying to enhance labor efficiency.

  • Upright positions allow gravity to contribute to descending the fetus, leading to shorter labor and stronger contractions.

  • Positions can also reduce pressure on significant blood vessels and alleviate backaches if the fetus is posterior.

  • Side-lying positions may help slow down precipitous births and enhance blood flow to the placenta.

Psychological Factors
Mother’s Psychological State

  • Factors such as anxiety, fear, and fatigue can significantly impact a woman's ability to cope with pain, enhancing the perception of pain and potentially impeding labor progression.

  • Preparation through childbirth education, relaxation techniques, and having support systems in place is vital.

  • Techniques include:
      - Relaxation of voluntary muscles.
      - Use of distraction, focal points, and imagery.
      - Breathing techniques with each contraction (e.g., starting with a cleansing breath through the nose and ending with a relaxing exhale).

Maternal Systemic Responses to Labor
Cardiovascular Response

  • During peak contractions, blood flow to the placenta decreases.

  • Blood volume may increase, impacting blood pressure and pulse rates.

  • Supine hypotension can occur if the mother lies flat on her back.

Respiratory Response

  • Increased anxiety and pain can lead to increased respiratory rates.

  • Hyperventilation may occur due to excessive carbon dioxide exhalation.

Renal Response

  • The fetus applies pressure to the bladder.

  • A full bladder does not impede labor or fetal descent; patients should be encouraged to urinate regularly.

  • An epidural may necessitate catheter insertion to manage bladder fullness.

Gastrointestinal Response

  • Reduced gastric motility; nausea and vomiting may occur.

  • Hydration through ice chips and clear liquids is typically encouraged.

Question #1

  • What are the 7 P’s?

Answer:

  1. Passageway

  2. Passenger

  3. Powers

  4. Position

  5. Psyche

  6. Pain

  7. Patience

Stages of Labor and Delivery

  1. First Stage: Dilation

  2. Second Stage: Delivery of Fetus

  3. Third Stage: Delivery of Placenta

  4. Fourth Stage: Recovery

Video Reference on Stages of Labor

  • Duration: 18:52.

First Stage Phases

  1. Latent Phase:
       - Dilation: 0 to 3 cm.
       - Contractions: 5-20 min apart, lasting 20-40 seconds.
       - Maternal emotions: talkative, alert, excited, relieved, anxious.
       - Pain level: Mild, easily controlled, with common backaches.
       - Nursing Care includes admission, orientation, therapeutic rapport, IV initiation, lab draws, monitoring, and assessments.

  2. Active Phase:
       - Dilation: 4 to 8 cm.
       - Contractions: 2-3 minutes apart, lasting ~60 seconds.
       - Maternal emotions: Less talkative, focused, may require more coping assistance.
       - Nursing interventions involve pain management, ongoing monitoring, and providing relaxation techniques.

  3. Transitional Phase:
       - Dilation: 8 to 10 cm.
       - Contractions: 2-3 minutes apart, lasting up to 90 seconds.
       - Maternal emotions: Focused, not talkative, irritable, may feel the urge to push.
       - Nursing care includes comfort measures, hygiene, assessment, and preparation for delivery.

Second Stage: Birth of Baby

  • Contractions last 60-90 seconds with emphasis on proper pushing techniques.

  • Immediate care includes managing the umbilical cord (potential nuchal cord), ensuring clear airway, stimulating and drying the infant.

  • Scores such as APGAR are noted at 1 and 5 minutes post-birth to assess the infant’s condition.

Third Stage: Delivery of Placenta

  • Length of this stage typically lasts 5 to 15 minutes; signs of placental detachment include cord lengthening and uterine shape change.

  • Risk of hemorrhage if parts are retained post-delivery.

Fourth Stage: Recovery

  • The “Golden Hour” after birth is crucial for bonding and breastfeeding success; it lasts until 2 hours post-delivery.

  • Key maternal assessments include monitoring vital signs, lochia, and fundal tone.

Question #2

  • What are the 3 phases of the 1st stage of labor?

Answer:

  1. Latent Phase

  2. Active Phase

  3. Transitional Phase

Conclusion

  • Understanding the labor process, including physiological mechanisms, monitoring, and nursing interventions is vital for effective management and support of laboring individuals.