Normal
Labor and Delivery
Physiological Adaptations
Chapter 17
Presented by
Amie
Bedgood
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
acm
e
Duration
Interval
Frequency
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)
Fill in the blank !

Length of a uterine contraction__________.

Strength of a uterine contraction is ___________.

The time from the beginning of one contraction to
the beginning of the next contraction is _______.

The time that allows for placental perfusion is __.
The peak of a contraction is also known as ____.


When the biparietal diameter of the head passes
through the pelvic inlet it is said to be ________.
CERVICAL ASSESSMENT

Dilation – is
expressed in
centimeters of the
size of the cervical
opening.

Effacement – is
estimated as a
percentage of the
amount the cervix
has thinned.

Full dilation = 10cm

Complete
effacement = 100%
Myometrial Activity
Effacement- thinning of the cervix (%)
Dilation – enlargement and widening of the os (cm)
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.
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
True or False?

The optimum lie of the fetus is the
longitudinal lie.
A. True
B. False
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 !

What is the reference point of a
cephalic presentation when the head
is fully flexed?
A.
B.
C.
d.
occiput
mentum
frontal
sagittal
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)
SHOW
Rupture of Membranes (ROM)
BACKACHE
DIARRHEA
SUDDEN INCREASE IN ENERGY
True vs False Labor

TRUE LABOR

FALSE LABOR

Contractions are:

Contractions are:
* Irregular



* Regular
* Increase in intensity and
duration with walking
* Felt in lower back,
radiating to lower portion
of abdomen
Bloody show
Dilation and effacement
Fetus usually engaged



* No change or decrease
with walking
* Contractions felt in
abdomen above
umbilicus:
Braxton Hicks
No change in cervix
Fetus is ballotable
Mechanisms of Labor/
Cardinal Movements
Descent
Flexion
Internal Rotation
Extension
External Rotation
Expulsion
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
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 and
move anteriorly
Increase in bloody show
Rectal pressure
Labia begins to part with each contraction
Signs of Stage Three of Labor
Globular
Shape of Uterus
Protrusion of
Umbilical cord
Fundus Rise in
Abdomen
Sudden Gush of
Blood
Fourth Stage of Labor

Recovery period after delivery and
bonding with the newborn.
 Last
from 1- 4 hours.
Nursing Care
Nursing
Assessment and
Interventions
during Labor and
Birth.
Technique for Assessing Fetal
Presentation and Position

Abdominal Palpation/Leopold’s Maneuver

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
 Step 2 - Go down each side and locate back
 Step 3 - Gently grasp lower portion of uterus
and feel for the head or buttock
 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
True or False ?

If the fetal heart tones (FHT’s) are
heard loudest (PMI) in the patient’s
upper right quadrant of her
abdomen, the fetus would be
assessed for a breech presentation.
A. True
B. False
Amniotic Membranes


Intact
Ruptured



Color




SROM
AROM
Clear
Yellow
Meconium
Amount
Vaginal Examination
 Presentation
(head/buttock)
– presenting part
– fetal head (OA, OP etc.)
 Condition of Membranes – ruptured or
 Position
intact
 Dilation - enlargement & widening of os (cm)
 Effacement
– thinning of the cervix
(%)
Vaginal Examination – cont’d
 Station- degree that the presenting part
has descended into the pelvis.
Relationship to ischial spines (-, 0, +)
 Engagement -largest diameter of
presenting part has passed through the
pelvic inlet
Try this !

When the cervical os widens or opens it is said
to________.

The level of the ________ _________ (bony structure) is
station zero.

The most common type of pelvis for a woman
____________.
When the cervix shortens and thins is _______________.


For delivery to occur, the fetus must accommodate to
this rigid passageway______________.
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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