PROCESS OF NORMAL LABOR

1
PROCESS OF NORMAL LABOR

• CHAPTER 7

2
Events Before Onset of Labor

• Unknown what actually starts labor
• Lightening baby drops down, baby settles in
  maternal pelvis
• Vaginal discharge or bloody show pink stained
  mucus
• Energy spurt or nesting time
• False labor no cervical dilatation
• Spontaneous rupture of membranes or SROM
• Cervical changes effacement dilatation
• see Figures 7-1,Table 7-1

3
Major Variables in the Birth Process The 4 Ps

• PELVIS--size and shape of the pelvis
• PASSENGER- fetus size and position
• POWERS-effectiveness of contractions
• PSYCHE-preparation, previous experience

4
PELVIS

• Must be adequate proportions in order for the
  fetal head to fit through
• Angles are downward, forward, upward somewhat
  like the letter J

5
PASSENGER

• Fetal Head must be able to stand extreme
  pressure
• Fetal Bony Skull bones thin, very elastic,
  allows for molding

6
Fetopelvic Relationship

• Terminology
• Attitude, fig 7-3
• Lie relationship of the longitudinal axis of
  the fetus to the mother, should be parallel, not
  crosswise
• Presentation, body part lowest in mothers
  pelvis, fig 7-4
• Position, more specific description of the
  relationship of the fetal presenting part to the
  maternal pelvis, fig 7-4
• Station fig 7-5, -5 to 5, ischial spines used,
  hardest to determine during a vaginal exam

7
POWERS-UTERINE CONTRACTIONS

• Involuntary
• Intermittent but regular
• Exhibit a wavelike pattern in 3 phases
• Increment, building up
• Acme, peak
• Decrement, decreasing intensity
• Affected by maternal position
• supine, more freq, lower intensity
• side lying, less freq, more effective

8
Assessment of Uterine Contractionsfig 7-6

• Frequency amount of time between the beginning
  of one contraction to the beginning of the next
• Duration time between the onset of the
  contraction its end
• Intensity strength of the contraction, rough
  estimate made by palpation
• mild easy to indent, like touching tip of
  nose
• moderate harder to indent but still able to
  touching the chin
• strong fundus is very firm difficult to
  indent, like touching the forehead

9
PSYCHE--Psychological and Cultural factors that
affect labor

• Anxiety and fear can decrease ability to cope,
  previous poor experience can effect present
  experience negatively
• Culture, ethnic background may play a strong role
  in the way a woman perceives labor and her
  reaction to it
• Maternal/newborn bonding very important!
  

10
MECHANISMS OF LABOR (cardinal movements)

• Figure 7-7
• Engagement and decent
• Flexion
• Internal rotation
• Extension
• Crowning
• External rotation
• Delivery of anterior shoulder
• Delivery of posterior shoulder
  expulsion

11
Placental expulsion

• 5-30 min after delivery s/s lengthening of
  cord--change in shape of uterus-trickle or gush
  of vaginal blood
• Dull- maternal side --Duncans mechanism or Dirty
  Duncanusually implanted low in uterus
• Shiny- fetal side- Schultzs mechanism or Shiny
  Schultzusually implanted high in uterus

12
FOUR STAGES OF LABOR

• 1ST STAGE begins with the onset of regular
  contractions until the cervix is fully dilated to
  10cm
• 2nd STAGE begins when cervix is fully dilated
  ends with birth of the infant
• 3rd STAGE begins with birth of the baby ends
  with expulsion of the placenta
• 4th STAGE from placental expulsion to the end
  of the recovery stage usually 1-4 hours

13
Phases of 1st STAGE OF LABOR-

• LATENT PHASE-EARLY STAGE 0-4CM EARLY, SLOW PART
• ACTIVE PHASE-MID PHASE 4CM-7CM STRONGER
  CONTRACTIONS
• TRANSITION PHASE-- LAST PART 8CM-10CM-CONTRACTIONS
  STRONGER, MORE FREQUENT LASTING 60-90 SECS
  WOMAN BECOMES IRRITABLE, ANXIOUS, SELF FOCUSED
  !!!!!

14
Second Stage of Labor

• Expulsion stage cervix 10 cm
• Coach-- do not hold breath more than 5 secs when
  pushing
• crowning of fetal headseen in external opening
  of vaginarecedes after contractions

• Second stage lasts from a few minutes to 2 hours
• episiotomy- midline or mediolateral
• support fetal head and check position of
  umbilical cord nuchal cord
• Birth relief for laboring woman

15
Third and Fourth Stage

• Third stage-
• Begins with birth to expulsion of placenta lasts
  up to 30 minutes
• Oxytocin (Pitocin) given to keep uterus firm and
  lessen blood loss after delivery of placenta

• Fourth stage-
• Recovery phase after delivery of placenta through
  first 1-4 hours or until VS stable. 250-500 ml
  blood loss. CRITICAL--Observe for excessive
  bleeding! Teach fundal massage.

16
Physiologic Changes in Laborsee table 7-2

• Cardiovascular- increase in b/p, supine
  hypotension, increased pulse rate
• Respiratory- 02 demand equal to strenous
  exercise, hyperventilationencourage to relax
  between contractions

• Renal--proteinuria, due to muscle breakdown
  distended bladder, due to pressure
• GI--peristalsis and absorption decrease--NPO
  except ice chips,
• hydration by IV