Stages of Labor and Childbirth

Pelvic Shapes and Functions

• Pelvic shapes: gynecoid (female pelvis), platypelloid, anthropoid, android (male pelvis)
• Functions of contractions:
  • Voluntary (actively pushing) and involuntary (use of intra-abdominal pressure)
  • Rhythmic, intermittent, can be altered with deflation, pain medication, illness, anxiety
• Effacement (softness of the cervix): 2cm thick cervix = 0% effaced, 1cm = 50% effaced, paper thin = 100% effaced

Premonitory Signs of Labor

• Cervical changes: softening of the cervix and possible dilation, effacement and dilation only possible once the cervix is soft
• Lightening: fetal presenting part descends into the pelvis, shape of abdomen changes, baby "dropped"
• Nesting: extra energy, typically 24-48 hours before labor, focused on getting ready for baby
• Bloody show: mucous plug expelled due to increased pressure and softening of the cervix, prevents bacteria from coming in
• Braxton Hicks: becomes stronger and more frequent, helps move the cervix from a posterior position to an anterior position, improves with walking, change in position, water, rest, voiding, and eating
• SROM: prelabor rupture of membranes, water breaks prior to onset of labor, must go to the hospital, note color, odor, amount, and time

Fetal Attitude, Lie, and Position

• Fetal attitude: amount of flexion, flexed is the typical and most favorable, want all joints flexed with rounded back, chin on chest, thighs on abdomen, legs flexed at the knees
• Fetal lie: relationship of the fetal spine to the maternal spine, longitudinal, only possible lie for vaginal delivery
• Fetal position: presenting part of the fetus to a designated point of the maternal pelvis, identify the presenting part, want occipital anterior position
• Fetal station: relationship of the presenting part with the maternal ischial spines, considered engaged when fetus is at 0 station, floating means the presenting part is above the pelvic inlet and is freely movable

True vs. False Labor

• True labor: regular, becomes closer together, usually 4-6 minutes apart, lasts 30-60 seconds, becomes stronger with time, vaginal pressure felt, starts in the back and radiates around toward the front of the abdomen
• False labor: irregular, not occurring close together, frequently weak, not getting stronger with time, usually felt in the front of the abdomen, contractions may stop or slow down with walking or making a position change

Vaginal Exams and Labor Progress

• Vaginal exams: way to assess labor progress, tells you dilation, effacement, station, presentation, position, attitude, and membrane status
• Dilation, effacement, station: measurements of labor progress

Labor Management

• Category 1: normal, predictive of normal acid-base balance, baseline FHR 110-160, moderate baseline variability, present or absent accelerations, present or absent decelerations, no late or variable decelerations, safe to monitor fetus intermittently, requires no interventions
• Category 2: intermediate, not predictive of abnormal fetus acid-base status, requires evaluation and continued surveillance, can include fetal tachycardia, fetal bradycardia, absent baseline variability, minimal or marked variability, recurrent late deceleration, and recurrent variable deceleration
• Category 3: abnormal, predictive of abnormal fetus acid-base status, requires intervention, includes fetal bradycardia, recurrent late decelerations, recurrent variable decelerations, and sinusoidal pattern

Maternal and Fetal Physiologic Responses to Labor

• Maternal:
  • Increased heart rate, cardiac output, and blood pressure
  • Increased WBC, respiratory rate, and oxygen consumption
  • Decreased gastric emptying and gastric pH
  • Slight temperature elevation
  • Muscle aches/cramps
  • Increased basal metabolic rate
  • Decreased blood glucose levels
• Fetal:
  • Periodic FHR accelerations and slight decelerations
  • Decrease in circulation and perfusion
  • Increase in arterial carbon dioxide pressure
  • Decrease in fetal breathing movements
  • Decrease in fetal oxygen pressure and partial pressure of oxygen

Stages of Labor

• First stage: longest stage, from 0-10cm, latent, active, and transitional phases
• Second stage: from complete dilation until birth of baby, latent and active phases
• Third stage: begins at the birth of the newborn and ends at the separation and birth of the placenta
• Fourth stage: begins after the delivery of the placenta, focuses on monitoring for hemorrhage, bladder distension, and venous thrombosis

Obstetric Emergencies

• Uterine rupture: tearing of the uterus at the site of a previous scar, symptoms include sudden fetal bradycardia, acute and continuous abdominal pain, vaginal bleeding, hematuria, and loss of fetal station
• Placental abruption: detachment of the placenta, symptoms include partial separation, concealed hemorrhage, and complete separation
• Placental previa: placenta partially or fully covering the internal os of the cervix, symptoms include sudden painless bleeding
• Umbilical cord prolapse: umbilical cord goes through the cervix and around the baby's neck, increased risk factors include breech, premature birth, and hydramnios

Pain Management in Labor

• Pharmacologic measures:
  • Regional analgesia/anesthesia
  • Pain relief without loss of consciousness
  • Obstetrical referring to loss of pain sensation
  • Epidural, combined spinal/epidural, and local infiltration
• Systemic analgesia:
  • Given PO, IM, or IV
  • Need to avoid giving before delivery due to CNS depression in the newborn
  • Opioids, antiemetics, and benzodiazepines
• Nonpharmacologic measures:
  • Continuous labor support
  • Hydrotherapy
  • Ambulation
  • Maternal position changes
  • Attention focusing and imagery
  • Therapeutic touch and massage
  • Gate control theory
  • Application of heat and cold
  • Breathing techniques

Dystocia

• Definition: abnormal progression of labor
• Causes: issues with powers, passenger, and passageway
• Types: failure to progress, including arrest in dilation and failure to descend

10 P's Factors Affecting Labor Process

• Passageway (birth canal)

• Passenger (fetus and placenta)

• Powers (contractions)

• Position (maternal)

• Psychological response

• Philosophy (low-tech/high touch)

• Partners (support)

• Patience (natural timing)

• Patient (client-childbirth knowledge base)

• Pelvic shapes### Labor Stages

• First stage: from 0-10cm dilation, divided into latent, active, and transitional phases

  • Latent phase: 0-4/6cm dilation, contractions q5-10 minutes, lasting 30-35 seconds, mild
  • Active phase: 6-10cm dilation, contractions q2-5 minutes, lasting 45-60 seconds, moderate
  • Transitional phase: 8-10cm dilation, faster progression, feels everything

• Second stage: from complete dilation to birth of baby, contractions q2-3 minutes, lasting 60-90 seconds

• Third stage: from birth of newborn to separation and birth of placenta, placental separation, uterus continues to contract

• Fourth stage: after delivery of placenta, beginning of postpartum period, monitoring vital signs, lochia, and for hemorrhage, bladder distension, and venous thrombosis

Obstetric Emergencies

• Uterine rupture: tearing of uterus at previous scar site, sudden fetal bradycardia, acute and continuous abdominal pain, vaginal bleeding, hematuria, loss of fetal station, hypovolemic shock
• Placental abruption: placenta detaches, partial or complete separation, concealed or apparent hemorrhage
• Placenta previa: placenta partially or fully covers internal os of cervix, sudden painless bleeding
• Umbilical cord prolapse: cord goes through cervix and around baby's neck, increased risk with breech, premature, and hydramnios

Pain Management

• Pharmacologic measures: regional analgesia/anesthesia, pain relief without loss of consciousness
• Epidural: may increase second stage labor, doesn't slow down labor, complications: hypotension, fetal distress, N/V, fever, pruritus, respiratory depression
• Combined spinal/epidural: rapid onset, limited duration, injection of anesthetic agent in subarachnoid space
• Local infiltration: pudendal block, provides long-lasting perineal analgesia, pain relief to lower vagina
• Systemic analgesia: given PO, IM, IV, need to avoid before delivery due to CNS depression in newborn
• Nonpharmacologic measures: continuous labor support, hydrotherapy, ambulation, maternal position changes, attention focusing and imagery, therapeutic touch and massage, gate control theory, application of heat and cold, breathing techniques

Signs of Shock

• Hypotension
• Increase HR/pulse
• Rapid respiration
• Hnh increase
• Peripheral cyanosis
• Hypovolemia
• Altered mental state
• Decreased urine output
• Weakness

Dystocia

• Definition: abnormal progression of labor, can be an issue with powers, passenger, or passageway
• Failure to progress: arrest in dilation, failure to descend, baby will be OP, eyes looking up and head facing mother's butt

Factors Affecting Labor Process

• Passageway (birth canal): bony pelvis is important, relaxin and estrogen work on soft tissue and ligaments for flexibility
• Passenger (fetus and placenta)
• Powers (contractions)
• Position (maternal)
• Psychological response
• Philosophy (low-tech/high touch)
• Partners (support)
• Patience (natural timing)
• Patient (client-childbirth knowledge base)
• Pelvic shapes: gynecoid, platypelloid, anthropoid, android