Normal
Labor and Delivery
Physiological Adaptations
Chapter 17
Presented by
Ann Hearn
LABOR
The process by
which the products of
conception are expelled
from the body
UTERINE CONTRACTIONS

Contraction - exhibits a wavelike pattern that
begins slowly climbing (increment) to a peak
(acme), and decreases (decrement)
acme

Intensity - strength of uterine contraction
Uterine Contractions
Duration- from beginning of one contraction to the end of the same
contraction
Frequency- from beginning of one contraction to the beginning of
another contraction
Interval - resting time between contractions allows for placental
perfusion
Uterine Contraction - review
Assessment of Contraction

1. Subjective symptoms by woman

2. Palpation and timing by the nurse

3. Use of Electronic Fetal Monitor
(EFM)
Upper 2/3 of
uterus
contracts
actively
Lower third
and cervix are
passive
These lead to downward progression of fetus
with each contraction
Uterine Muscle
CERVICAL ASSESSMENT

Dilation:
the size of the
cervical opening
(measured in
centimeters).

Effacement:–
estimated amount
the cervix has
thinned (measured
in percent)

Full dilation = 10cm

Complete
effacement = 100%
Myometrial Activity
Effacement- thinning of the cervix (%)
Dilation – enlargement and widening of the os (cm)
 During
each contraction, blood flow to
the placenta gradually decreases,
resulting in an increase in the woman’s
blood volume causing her B/P to
increase and slowing of her pulse.
 Because
these changes occur during a
contraction, it is best to assess vital
signs between contractions.
 During
labor a woman is likely to
hyperventilate causing:
 Tingling
in hands and feet
 Numbness
 Dizziness
Have the woman slow
her breathing, breath
into her hands or a
paper bag.
 Most
woman are limited to clear liquids
or NPO during the labor process.
 Gastric
motility and digestion of food is
reduced.
 Decrease risk of aspiration
Intense
contractions
Reduce sensations
of needing to void
Anesthesia
Inhibit fetal
descent or
(increased
discomfort if no
anesthesia)
Unaware of having
a Full bladder
 EBL
= Estimated blood loss
 Vaginal
delivery ~ 500ml
 cesarean birth ~1000ml
 Clotting
factors are elevated and
Fibrinolyis is decreased to promote
coagulation at the placental site
Passenger
Passageway
Essential
Factors
in
Labor
Psychological
Powers
THE
POWERS
Major Powers Involved

Primary Force:
 Involuntary


Uterine Contractions or
Muscular contractions which lead to dilation
and effacement in the First Stage of Labor
Secondary Force:
 Voluntary

Uterine Contractions or
Abdominal muscles assist in the Second
Stage of Labor with pushing. Increase intraabdominal pressure to aid in expulsive
forces
THE
PASSAGEWAY
THE PELVIS

Determine if the pelvic cavity is of
adequate size to allow for the
passage of the full term infant
Optimum shaped pelvis is Gynecoid
THE PELVIS
False Pelvis


Supports the
weight of the
uterus
Shallow basin
above the inlet
or brim
True Pelvis
 Represents
the bony
limits of the
birth canal
True Pelvis vs False Pelvis
True Pelvis
Inlet - upper margin of symphysis pubis to the
upper margin of sacrum
Midpelvis - level of the ischial spines
Outlet - Lower pubic bone to tip of coccyx.
This area is the smallest portion that
the baby must travel through.
Station
Station- degree that the
presenting part has
descended into the pelvis
in relationship to ischial
spines.
Goal: Move from
– to + stations
Engagement

Descent of the fetal presenting part
in relation to the ischial spines of the
maternal pelvis = 0 station.
Engagement
Engagement
Ballotable
-largest diameter of
presenting part has
passed through the
pelvic inlet
-
Assessed during
vaginal exam
Engaged
THE
PASSENGER
And
PPRESENTATION
Fetal Head
Because of its size and rigidity,
the fetal head has a major
impact on delivery.
The bones are not firmly united.
There are sutures between the
bones that allow them to
overlap or MOLD to the birth
canal.
Head also can rotate, flex, and
extend
Fetal Lie

Relationship of the long axis of the
fetus to the long axis of the mother.
Longitudinal Lie
Transverse Lie
Attitude
Relationship
of fetal body
parts to
each other
Optimum
attitude is
flexion or
ovoid
Fetal Presentation
The portion of the fetus that enters
the pelvis first
 Three Types:

 Cephalic
 Breech
 Shoulder
Reference Points
of Presentation

Cephalic = Head
 Vertex,

Breech = Buttock or Foot
 Frank,

Military, Brow, Face
Full, Footling
Shoulder = Transverse lie
Cephalic Presentations
Breech Presentations
Position
Position
Relationship of the Fetal Presenting
Part to the Maternal Pelvis
 Steps:

1. Determine the Presenting Part
2. Divide the mothers pelvis into 4 imaginary quadrants
A
12
R
9
3
6
P
L
Test Yourself





Overlapping of the fetal skull to facilitate its
passage through the bony pelvis is ___________.
Relationship of fetal body parts to each other
is_____________.
Head first presentation is_________________.
Relationship of the fetal spine to the maternal
spine is ________________.
Term that refers to the part of the fetus that
enters the pelvic inlet first is _____________.
THE
PSYCHOLOGICAL
BREAK THE CYCLE !
FEAR
TENSION
PAIN
CAUSES OF LABOR
Decrease in Progesterone
Increase in Estrogen
High levels
of
Prostaglandins
Over-distention
of
Uterus
Degeneration
of
Placenta
Premonitory Signs of Labor
The impending signs
that take place the last
several weeks of
pregnancy or even the
last several days
Premonitory Signs of Labor
 Lightening
 False Labor Pain (Braxton Hicks)
 Bloody Show
 Increased clear vaginal secretions
 Small weight loss (~3 pounds)
 Sudden increase in energy
True vs False Labor
 TRUE




LABOR
Contractions are:
* Regular
* Increase in intensity and
duration with walking
* Felt in lower back,
radiating to lower portion
of abdomen
Dilation and effacement
Fetus usually engaged
Progressive changes in
the cervix

FALSE LABOR


Contractions are:
* Irregular

* No change or decrease
with walking
* Contractions felt in
abdomen above
umbilicus:
Braxton Hicks
No change in cervix
Phases and Stages of Labor
 Stage 1:
0 - 10 cm.
 Phase 1 - Latent - dilate 0 - 3 cm.
 Phase 2 - Active - dilate 4 - 7 cm.
 Phase 3 - Transition - dilate 8 - 10 cm
 Stage 2: From complete dilation and
effacement to delivery of the baby
 Stage 3: From delivery of baby to the
delivery of the placenta
 Stage 4: the first hour after delivery
Signs of Second Stage of Labor
Complete dilatation of cervix
Urge to bear down
Perineum begins to bulge, flatten
Increase in bloody show
Rectal pressure
Labia begins to part with each contraction
Mechanisms of Labor/
Cardinal Movements
Descent
Flexion
Internal Rotation
Extension
External Rotation
Expulsion
Signs of Stage Three of Labor
Globular
Shape of Uterus
Protrusion of
Umbilical cord
Fundus Rise in
Abdomen
Sudden Gush of
Blood
Placenta

Fetal side (Schultze)

Maternal side (Duncan)
Forth Stage of Labor

Recovery period after delivery and
bonding with the newborn.
 Last
from 1- 4 hours.
When To Go To The Hospital
 Regular
uterine contractions
 Rupture of Membranes (ROM)
 Red vaginal Bleeding
 Decreased Fetal Movement
 Other concerns
Nursing Care


Establish Relationship
Nursing Assessment:



Maternal and Fetal
Interview
Interventions during
labor and birth.
Leopold’s (1 of 4)
Technique for Assessing Fetal Presentation and Position
Standing on the right side, face the woman and palpate
with the palms of the hands.
Step 1 - Start at upper fundus and palpate for the head
or
buttocks
Leopold’s (2 of 4)
Step 2 - Go down each side and locate
smooth back or “lumpy” extremities.
Leopold’s (3 of 4)
Step 3 - Gently grasp lower portion of uterus and
feel for the head or buttock
Leopold’s (4 of 4)
Step 4 - Turn and face the woman feet, using both hands
palpate lower abd. for cephalic prominence or brow.
Ausculation

Assess for the area of greatest
intensity of the FHR.
 Usually
best heard at the fetal back
Vaginal Examination

Presentation – presenting part (head/buttock)
Position – fetal head (OA, OP etc.)
 Dilation - enlargement & widening of os (cm)


Effacement – thinning of the cervix (%)

Condition of Membranes – ruptured or intact
Vaginal Examination – cont’d

Station- degree that the presenting part
has descended into the pelvis.
Relationship to ischial spines
(ballotable, -, 0, +)

Engagement - largest diameter of
presenting part has passed through the
pelvic inlet
Amniotic Membranes


Intact
Ruptured



Color





SROM
AROM
Clear
Yellow
Meconium
Amount
Odor
Duration of Labor
Resistance of the Cervix
 Presentation and position of the
fetus
 The woman’s pelvis
 Preparation and relaxation of the
mother
 Primigravida - up to 22 hrs; average 12 1/2 hrs
 Multigravida - 8 - 17 hrs; average 10 hrs.


The End
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