16953799 Labor and Delivery
Content
Theories of Labor Onset
1. Uterine stretch theory – any
hallowed organ when stretched to its
maximum capacity will contrast and
empty.
2. Oxytocin theory – Oxytocin, which
causes contractions of the smooth
muscles of the posterior pituitary
gland as a result of stressful event in
labor.
3. Progesterone
Deprivation
Theory – Progesterone, secreted by
the corpus Luteum and then by the
placenta, is essential in maintaining
pregnancy. However, the decrease in
the level of progesterone circulating
in the body will initiate body pains.
4. Prostaglandin
Theory
–
Prostaglandins,
formed
by
the
uterine deciduas under level of
concentration in the amniotic fluid
and blood of women increases
during labor. Research has shown
prostaglandin to be very effective in
inducing uterine contraction at any
stage of gestation. Initiation of labor
is said to be the result of the release
of arachidonic acid is believed to
increase prostaglandin synthesis
contractions.
5. Theory of Aging Placenta – as the
placenta matures, blood supply
decreases
resulting
in
uterine
contractions.
Related Terms:
Labor – is the process of moving the
fetus, placenta and membranes out of
the uterus and through the birth
canal. Synonymous with childbirth and
parturition.
Delivery – is the actual birth of baby
Crowning – encircling of the largest
diameter of the baby’s head by the
vulvar ring
Effacement – shortening and thinning
of the cervical canal. It is expressed in
percentage (%).
Dilatation – is the enlargement of the
cervical os from an orifice a few
millimeters in size to an aperture large
enough to permit the passage of the
fetus.
Show – is a mucoid discharge from the
cervix that is present after the
mucous plug has been discharged.
Attitude – the relationship of the fetal
parts to one another
Lie – relationship of the fetal spine to
the spine of the mother.
Presentation – portion of the fetus that
enters the pelvis first.
Position – relationship of the assigned
area of the presenting part of the
landmark of the material pelvis.
Station – measurement of the
progress of descent of the presenting
part in relation to the ischial spine.
Frequency – from the beginning of one
contraction to the beginning of the
next contraction
Duration – from the beginning of
contraction to its completion
Intensity – the strength of contraction
to its completion
Effacement – progressive thinning and
shortening of the cervix
Dilatation – opening of the cervix os
during labor
SIGNS of LABOR
Preliminary/Prodromal Signs of Labor
1. Ligthening – setting of fetal head
into pelvic brim
occurs approximately 10-14
days before labor begins
gives the woman relief from
diaphragmatic pressure and
shortness of breath
occurs early in primiparas
mother
may
experience:
shooting leg pains from the
increased pressure on the
sciatic
nerve,
increased
amounts of vaginal discharge
and urinary frequency from
pressure on the bladder
2. Increased in Level of Activity –
related
to
an
increase
in
epinephrine release that is initiated
by a decrease in progesterone
produced by the placenta
3. Braxton
Hicks
Contractions
–
painless
irregular
contractions,
sometimes strong that may cause
discomfort
4. Ripening of the cervix – Goodell’s
sign: the cervix feels softer than
normal
similar
to
earlobe
throughout pregnancy; at term
cervix is described butter-soft
Signs of TRUE LABOR:
1. Uterine Contractions – surest sign
that labor has begun
2. Show – the blood mixed with
mucus, takes on a pink tinge. It is
when mucus plug is expelled and
capillaries are exposed.
3. Rupture of the membranes –
experienced either as a sudden
gush or as a scanty, slow seeping
of clear fluid from the vagina.
False Labor:
Irregular contractions
Pain is confined to the abdominal
No increase in duration, frequency, and
intensity.
Pain disappears with ambulating
No cervical change
Sedation stops contractions
True Labor:
Regular contractions
Pain on the lower back to the abdomen
Increase in duration, frequency and
intensity
Pain not relieved upon ambulating
Accompanied with effacement and
dilatation
Sedation does not stop contraction
CHARACTERISTICS of CONTRACTIONS
1. Mild – uterine muscle are somewhat
tense but can be indented by a
gentle pressure
2. Moderate – uterus is moderately firm
and a firmer pressure is needed to
indent
3. Strong – the uterus becomes very
firm that at the height of contraction
cannot be indented.
COMPONENTS of LABOR
1. Passage – refers to the shape and
measurement of maternal pelvis and
distensibility of birth canal
– refers to the route a fetus
must travel from the uterus
through the cervix and
vagina to the external
perineum.
– Elastic to expand and
accommodate
4 Basic Classification of Pelvis:
a. Gynecoid – best pelvis; half of
the population
b. Android – common in men, 20%
in women; heart shape and difficult for
vaginal delivery
c. Anthropoid – common in men;
20-30%, pelvic inlet oval
d. Platypelloid – flat pelvis; least
common; 5% of the population, long
sacrum
2. Passenger – refers to the fetus, its
size, presentation, and position.
3. Power – forces acting together to
expel fetus from the uterus
2 TYPES of POWER
a. Primary Powers – involuntary
contractions of the uterus
b. Secondary Powers- voluntary bearing
down efforts of the mother
4. Psyche – reflects the woman’s
frame of mind in dealing with the
labor experience
Structure of the fetal skull
Cranium – uppermost portion of
the skull, comprises eight bones.
- the four bones: the frontal
(actually 2 fused bones), 2
parietal and occipital.
- The other four: sphenoid,
ethmoid, and 2 temporal
bones
The Suture Lines:
Sagittal suture- joins the 2 parietal
bones of the skull
Coronal suture – the line of juncture
of the frontal bones and the 2
parietal bones
Lambdoid suture – the line of
juncture of the occipital bone
and 2 parietal bones.
Fontanelles:
- significant membrane-covered
spaces that are found at the junction
of the main suture lines
Anterior Fontanelle – referred to as
bregma; lies at the junction of the
coronal and sagittal sutures
- diamond-shape
- anteroposterior diameter is
3-4cm
- transverse diameter is 23cm
Posterior Fontanelle – lies at the
junction of the lambdoidal and sagittal
sutures.
- triangular
- smaller than the anterior
Fontanelle
- only 2cm across its widest
part
Vertex – the space between two
fontanelles
Sinciput – the area over the frontal
bone
Occiput – the area over the occipital
bone
Suboccipitobregmatic – narrowest
diameter 9.5cm; from the inferior aspect
of the occiput to the center of the
anterior fontanelle
Occipitofrontal – measured from the
bridge of the nose to the occipital
prominence is 12cm
Occipitomental – the widest which is
13.5cm; measured from the chin to the
posterior fontanelle
Molding – the change in shape of the
fetal skull produced by the force of
uterine contractions pressing the vertex
of the head against the not-yet-dilated
cervix.
Station – refers to the relationship of the
presenting part of a fetus to
the level of ischial spines
0 station – presenting part of a fetus is
at the level of the ischial
spines
-4 station – head is at outlet
+4 station – head is floating
FETAL LIE – the relationship between the
long axis of the body and the
long axis of a woman’s body
2 Primary Lie
1. Longitudinal
2. Transverse
FETAL PRESENTATIONS – denote the body
part that will first contact the
cervix of be born first.
- this is determined by a
combination of fetal lie and
the degree of flexion
3 Main Presentations
FETAL PRESENTATION and POSITION
Attitude – describes the degree of flexion
a fetus assumes during labor or the
relation of fetal parts to each other
1) Good Attitude (complete flexion) –
the spinal column is bowed forward
that the chin touches the sternum,
the arms are flexed and folded on
chest, the thighs are flexed onto
the abdomen and the calves are
pressed against the posterior
aspect of the thighs.
2) Moderate flexion – the chin is not
touching the chest but is in an alert
or military position
3) Poor flexion – the back is arched,
the neck in extended and a fetus is
in complete extension, presenting
the occipitomental diameter of the
head to the birth canal (face
presentation)
a. Cephalic – the fetal head is the body
part that will first contact the
cervix
- the four types of cephalic
presentation: vertex, brow,
face and mentum
b. Breech – either the buttocks or the
feet are the first body part
that will contact the cervix
- the 3 type of breech presentation:
complete, frank, and footling)
c. Shoulder – the presenting part is
usually one of the shoulders
(acromion process, an iliac
crest, a hand, or an elbow
POSITION – the relationship of the
presenting part to a specific
quadrant of a woman’s pelvis
UTERINE CONTRACTIONS:
Engagement – refers to the settling of
the presenting part of a fetus far enough
into the pelvis to be at the level of the
ischial spines.
Floating – a presenting part that is not
engaged
Dipping – one that is descending but
has not yet reached the
ischial spines
Origins
Labor contractions begin a
“pacemaker” point located in the
myometrium near one of the
uterotubal junctions
In some women, contractions
appear to originate in the lower
uterine segment rather than in the
fundus.
Phases
3 Phases: increment, acme,
decrement
Increment- when the intensity of
the contraction increases
Acme- when the contraction is at
its strongest
Decrement- when the intensity
decreases
As labor progresses the relaxation
intervals decrease from 10 minutes
to 2 – 3 minutes
The duration also changes from 2030 sec to a range of 60-90 sec
Contour Changes
Upper segment becomes thicker
and active, preparing it to be able
to exert the strength necessary to
expel the fetus when the expulsion
phase of labor is reached
The lower segment becomes thinwalled, supple, and passive so that
the fetus can be pushed out of the
uterus easily
Physiologic retraction ring – a ridge
on the inner uterine surface that
marks the boundary between the 2
portions
Pathologic retraction ring (Bandl’s
ring) – it is a danger sign that
signifies impending rupture of the
lower uterine segment if the
obstruction to labor is not relieved
Cervical Changes
Effacement
Shortening and thinning of
the cervical canal
Normally the canal is 1-2cm
With effacement the canal
virtually disappears because of
longitudinal traction from the
contracting uterine fundus
Dilation
Refers to the enlargement or
widening of the cervical canal from
an opening of few millimeters wide
to one large enough (10cm).
First reason why dilation occurs is
uterine contractions gradually
increase the diameter of the
cervical canal lumen by pulling the
cervix up over the presenting part
of the fetus
Second, the fluid-filled membranes
press against the cervix
As dilation begins there is large
amount of vaginal secretions
(show) because the last of the
operculum or mucus plug in the
cervix is dislodged and capillaries
in the cervix rupture
STAGES OF LABOR
1. Stage 1 (stage of dilatation) – begins
with the true labor pains and ends when
the cervix has reached full dilatation
Nursing Care:
Stay with woman; provide constant
support
Reminds, reassures and encourages
woman to reestablish breathing
patterns and concentration as needed
Prompts partial respirations if woman
begins to push prematurely accepts
woman inability to comply with
instructions
Keeps woman aware of progress
4 Phases:
Latent Phase
Begins at the regularly
perceived uterine contractions
and ends when rapid cervical
dilatation begins
Contractions are mild and short
lasting 20-40 seconds
Cervix dilates from 0-3cm
6 hours in nullipara
4.5 hours in multipara
Nursing Care:
- Assists woman to cope with
contraction
- Helps to concentrate in
breathing techniques
- Assists into comfortable
position
- Informs woman of the
progress of labor
- Explains procedure and
routines
- Offer fluids, ice chips, food
as ordered
Active Phase
Dilatation increases from 4 – 7
cm
Contraction lasts 40-60 sec and
occur every 3-5 minutes
3 hours in nullipara
2 hours in multipara
Show and spontaneous rupture
of membranes may occur
Nursing Care:
- Finds assessment
techniques between
contractions
- Assists with frequent
position change
- Applies counter pressure to
sacrococcygeal area
- Encourages and praises
- Keeps woman aware of
progress
- Check bladder and
encourages voiding
- Gives oral care
Transition Phase
Contractions reached their peak
of intensity occurring every 2-3
minutes with duration of 6090sec
Maximum dilatation 8-10cm
Complete cervical effacement
Woman experiences intense
discomfort accompanied by
nausea and vomiting
Woman may also experience a
feeling of loss of control,
anxiety, panic or irritability
2. Stage 2 (Stage of Expulsion) – the
period from full dilatation to birth of the
infant
Contractions change from the
characteristic crescendodecrescendo pattern to
overwhelming uncontrollable urge
to push or bear down with each
contraction as if to move her
bowels
Woman perspire and the blood
vessels in her neck may become
distended
Crowning takes place
The need to push become
intense and the woman cannot
stop herself
6 Cardinal Movements of the
Mechanism of labor
o Descent – downward movement of
the biparietal diameter of the fetal
head to within the pelvic inlet
- full descent occurs and the
fetal head extrudes beyond
the dilated cervix and
touches the posterior
vaginal floor
o Flexion – the head bends forward
onto the chest, making the
smallest anteroposterior diameter
o Internal rotation – the occiput
rotates until it is superior, or just
below the symphysis pubis,
bringing the head into the best
relationship to the outlet of the
pelvis
o Extension – as the occiput is born,
the back of the neck stops beneath
the pubic arch and acts as a pivot
for the rest of the head. The head
extends, and the foremost parts of
the head, the face and chin are
born.
o External Rotation – almost
immediately after the head of the
infant is born, the head rotates
(from the anteroposterior position
it assumed to enter the outlet)
back to the diagonal or transverse
position of the early part of labor
o Expulsion – the rest of the baby is
born easily and smoothly because
of its smaller part size. The end of
the pelvic division of labor.
Nursing Care:
Put both legs at the same
time when positioning to the
lithotomy position
Instruct mother to push as
fetal head crowns. If
hyperventilation occurs, let patient
breathe into a brown paper or a
cupped hand.
3. Stage 3 (Placental Stage) – begins
from the delivery of the baby up to
the delivery of the placenta
2 Phases:
a. Placental Separation
Signs:
- Lengthening of the cord
- Sudden gush of blood
- Change of shape of the
uterus
b. Placental Expulsion
- Brandt Andrew’s Maneuver – tract
the cord slowly, winding it around the
clamp until placenta spontaneously
comes out rotating it slowly so that no
membranes are left
Nursing Care:
Don’t hurry the expulsion of the
placenta, just watch for the signs of
placental separation
Take note of the time of placental
delivery
Inspect for the completeness of the
placenta
Palpate the uterus to determine
degree of contraction. If relaxed,
massage gently and apply ice cap
Inspect for lacerations
Types of Placental Presentation
Schultze’s – appearing shiny and
glittering from the fetal
membranes
Duncan – it looks raw, dirty,
meaty, red and irregular
4. Stage 4 (Puerperium Stage) – first 4
hours after delivery of placenta
Degrees of Perineal Lacerations:
1. First Degree – skin and superficial to
muscle
2. Second Degree – muscles of the
perineum
3. Third Degree – continues to anal
sphincter
4. Fourth Degree – involves the anterior
anal wall
Episiotomy – incision made to the
perineum to enlarge the vaginal opening
for easy delivery
Types:
a. Midline/Median
b. Mediolateral
c. Lateral
Advantages:
1. Enlarging of the vaginal opening
2. Shortening of the second stage of
labor
3. Minimizing the stretching of the
perineal muscle
4. Preventing perineal tearing
Fetal Monitoring – periodic change or
fluctuation in FHR occur in response to
contractions and the fetal movements
are described in terms of accelerations or
decelerations
- done through intermittent
auscultation
- electronic monitoring
1. External – transabdominal,
noninvasive, monitors uterine contraction
and FHR; client needs to decrease extraabdominal movements
2. Internal – membranes must be
ruptured, cervix sufficiently dilated and
presenting part; invasive procedure;
continuous monitoring
- results of monitoring: normal FHR
120-160; must obtain a baseline
Acceleration – 15 bpm rise above
baseline followed by return; usually in
response to fetal movement or
contractions; indicates fetal well-being
Deceleration – fall below baseline lasting
15 seconds or more, followed by a return:
a. Early Deceleration – are periodic
decreases in the FHR resulting from
pressure on the fetal head during
contraction (head compression)
b. Late Deceleration – indicative of
fetal hypoxia because of deficient
placental perfusion (uteroplacental
insufficiency)
c. Variable Deceleration – occurs at
unpredictable times during contractions
and indicates cord compression
Anesthesia – encompasses analgesia
amnesia, relaxation and reflex activity. It
abolishes pain perception by interrupting
the nerve impulses to the brain. The loss
of sensation may be partial incomplete,
sometimes with loss of consciousness.
Analgesia – refers to the alleviation of the
sensation of pain or in the raising of the
threshold for pain perception without loss
of consciousness
1. Uterine stretch theory – any
hallowed organ when stretched to its
maximum capacity will contrast and
empty.
2. Oxytocin theory – Oxytocin, which
causes contractions of the smooth
muscles of the posterior pituitary
gland as a result of stressful event in
labor.
3. Progesterone
Deprivation
Theory – Progesterone, secreted by
the corpus Luteum and then by the
placenta, is essential in maintaining
pregnancy. However, the decrease in
the level of progesterone circulating
in the body will initiate body pains.
4. Prostaglandin
Theory
–
Prostaglandins,
formed
by
the
uterine deciduas under level of
concentration in the amniotic fluid
and blood of women increases
during labor. Research has shown
prostaglandin to be very effective in
inducing uterine contraction at any
stage of gestation. Initiation of labor
is said to be the result of the release
of arachidonic acid is believed to
increase prostaglandin synthesis
contractions.
5. Theory of Aging Placenta – as the
placenta matures, blood supply
decreases
resulting
in
uterine
contractions.
Related Terms:
Labor – is the process of moving the
fetus, placenta and membranes out of
the uterus and through the birth
canal. Synonymous with childbirth and
parturition.
Delivery – is the actual birth of baby
Crowning – encircling of the largest
diameter of the baby’s head by the
vulvar ring
Effacement – shortening and thinning
of the cervical canal. It is expressed in
percentage (%).
Dilatation – is the enlargement of the
cervical os from an orifice a few
millimeters in size to an aperture large
enough to permit the passage of the
fetus.
Show – is a mucoid discharge from the
cervix that is present after the
mucous plug has been discharged.
Attitude – the relationship of the fetal
parts to one another
Lie – relationship of the fetal spine to
the spine of the mother.
Presentation – portion of the fetus that
enters the pelvis first.
Position – relationship of the assigned
area of the presenting part of the
landmark of the material pelvis.
Station – measurement of the
progress of descent of the presenting
part in relation to the ischial spine.
Frequency – from the beginning of one
contraction to the beginning of the
next contraction
Duration – from the beginning of
contraction to its completion
Intensity – the strength of contraction
to its completion
Effacement – progressive thinning and
shortening of the cervix
Dilatation – opening of the cervix os
during labor
SIGNS of LABOR
Preliminary/Prodromal Signs of Labor
1. Ligthening – setting of fetal head
into pelvic brim
occurs approximately 10-14
days before labor begins
gives the woman relief from
diaphragmatic pressure and
shortness of breath
occurs early in primiparas
mother
may
experience:
shooting leg pains from the
increased pressure on the
sciatic
nerve,
increased
amounts of vaginal discharge
and urinary frequency from
pressure on the bladder
2. Increased in Level of Activity –
related
to
an
increase
in
epinephrine release that is initiated
by a decrease in progesterone
produced by the placenta
3. Braxton
Hicks
Contractions
–
painless
irregular
contractions,
sometimes strong that may cause
discomfort
4. Ripening of the cervix – Goodell’s
sign: the cervix feels softer than
normal
similar
to
earlobe
throughout pregnancy; at term
cervix is described butter-soft
Signs of TRUE LABOR:
1. Uterine Contractions – surest sign
that labor has begun
2. Show – the blood mixed with
mucus, takes on a pink tinge. It is
when mucus plug is expelled and
capillaries are exposed.
3. Rupture of the membranes –
experienced either as a sudden
gush or as a scanty, slow seeping
of clear fluid from the vagina.
False Labor:
Irregular contractions
Pain is confined to the abdominal
No increase in duration, frequency, and
intensity.
Pain disappears with ambulating
No cervical change
Sedation stops contractions
True Labor:
Regular contractions
Pain on the lower back to the abdomen
Increase in duration, frequency and
intensity
Pain not relieved upon ambulating
Accompanied with effacement and
dilatation
Sedation does not stop contraction
CHARACTERISTICS of CONTRACTIONS
1. Mild – uterine muscle are somewhat
tense but can be indented by a
gentle pressure
2. Moderate – uterus is moderately firm
and a firmer pressure is needed to
indent
3. Strong – the uterus becomes very
firm that at the height of contraction
cannot be indented.
COMPONENTS of LABOR
1. Passage – refers to the shape and
measurement of maternal pelvis and
distensibility of birth canal
– refers to the route a fetus
must travel from the uterus
through the cervix and
vagina to the external
perineum.
– Elastic to expand and
accommodate
4 Basic Classification of Pelvis:
a. Gynecoid – best pelvis; half of
the population
b. Android – common in men, 20%
in women; heart shape and difficult for
vaginal delivery
c. Anthropoid – common in men;
20-30%, pelvic inlet oval
d. Platypelloid – flat pelvis; least
common; 5% of the population, long
sacrum
2. Passenger – refers to the fetus, its
size, presentation, and position.
3. Power – forces acting together to
expel fetus from the uterus
2 TYPES of POWER
a. Primary Powers – involuntary
contractions of the uterus
b. Secondary Powers- voluntary bearing
down efforts of the mother
4. Psyche – reflects the woman’s
frame of mind in dealing with the
labor experience
Structure of the fetal skull
Cranium – uppermost portion of
the skull, comprises eight bones.
- the four bones: the frontal
(actually 2 fused bones), 2
parietal and occipital.
- The other four: sphenoid,
ethmoid, and 2 temporal
bones
The Suture Lines:
Sagittal suture- joins the 2 parietal
bones of the skull
Coronal suture – the line of juncture
of the frontal bones and the 2
parietal bones
Lambdoid suture – the line of
juncture of the occipital bone
and 2 parietal bones.
Fontanelles:
- significant membrane-covered
spaces that are found at the junction
of the main suture lines
Anterior Fontanelle – referred to as
bregma; lies at the junction of the
coronal and sagittal sutures
- diamond-shape
- anteroposterior diameter is
3-4cm
- transverse diameter is 23cm
Posterior Fontanelle – lies at the
junction of the lambdoidal and sagittal
sutures.
- triangular
- smaller than the anterior
Fontanelle
- only 2cm across its widest
part
Vertex – the space between two
fontanelles
Sinciput – the area over the frontal
bone
Occiput – the area over the occipital
bone
Suboccipitobregmatic – narrowest
diameter 9.5cm; from the inferior aspect
of the occiput to the center of the
anterior fontanelle
Occipitofrontal – measured from the
bridge of the nose to the occipital
prominence is 12cm
Occipitomental – the widest which is
13.5cm; measured from the chin to the
posterior fontanelle
Molding – the change in shape of the
fetal skull produced by the force of
uterine contractions pressing the vertex
of the head against the not-yet-dilated
cervix.
Station – refers to the relationship of the
presenting part of a fetus to
the level of ischial spines
0 station – presenting part of a fetus is
at the level of the ischial
spines
-4 station – head is at outlet
+4 station – head is floating
FETAL LIE – the relationship between the
long axis of the body and the
long axis of a woman’s body
2 Primary Lie
1. Longitudinal
2. Transverse
FETAL PRESENTATIONS – denote the body
part that will first contact the
cervix of be born first.
- this is determined by a
combination of fetal lie and
the degree of flexion
3 Main Presentations
FETAL PRESENTATION and POSITION
Attitude – describes the degree of flexion
a fetus assumes during labor or the
relation of fetal parts to each other
1) Good Attitude (complete flexion) –
the spinal column is bowed forward
that the chin touches the sternum,
the arms are flexed and folded on
chest, the thighs are flexed onto
the abdomen and the calves are
pressed against the posterior
aspect of the thighs.
2) Moderate flexion – the chin is not
touching the chest but is in an alert
or military position
3) Poor flexion – the back is arched,
the neck in extended and a fetus is
in complete extension, presenting
the occipitomental diameter of the
head to the birth canal (face
presentation)
a. Cephalic – the fetal head is the body
part that will first contact the
cervix
- the four types of cephalic
presentation: vertex, brow,
face and mentum
b. Breech – either the buttocks or the
feet are the first body part
that will contact the cervix
- the 3 type of breech presentation:
complete, frank, and footling)
c. Shoulder – the presenting part is
usually one of the shoulders
(acromion process, an iliac
crest, a hand, or an elbow
POSITION – the relationship of the
presenting part to a specific
quadrant of a woman’s pelvis
UTERINE CONTRACTIONS:
Engagement – refers to the settling of
the presenting part of a fetus far enough
into the pelvis to be at the level of the
ischial spines.
Floating – a presenting part that is not
engaged
Dipping – one that is descending but
has not yet reached the
ischial spines
Origins
Labor contractions begin a
“pacemaker” point located in the
myometrium near one of the
uterotubal junctions
In some women, contractions
appear to originate in the lower
uterine segment rather than in the
fundus.
Phases
3 Phases: increment, acme,
decrement
Increment- when the intensity of
the contraction increases
Acme- when the contraction is at
its strongest
Decrement- when the intensity
decreases
As labor progresses the relaxation
intervals decrease from 10 minutes
to 2 – 3 minutes
The duration also changes from 2030 sec to a range of 60-90 sec
Contour Changes
Upper segment becomes thicker
and active, preparing it to be able
to exert the strength necessary to
expel the fetus when the expulsion
phase of labor is reached
The lower segment becomes thinwalled, supple, and passive so that
the fetus can be pushed out of the
uterus easily
Physiologic retraction ring – a ridge
on the inner uterine surface that
marks the boundary between the 2
portions
Pathologic retraction ring (Bandl’s
ring) – it is a danger sign that
signifies impending rupture of the
lower uterine segment if the
obstruction to labor is not relieved
Cervical Changes
Effacement
Shortening and thinning of
the cervical canal
Normally the canal is 1-2cm
With effacement the canal
virtually disappears because of
longitudinal traction from the
contracting uterine fundus
Dilation
Refers to the enlargement or
widening of the cervical canal from
an opening of few millimeters wide
to one large enough (10cm).
First reason why dilation occurs is
uterine contractions gradually
increase the diameter of the
cervical canal lumen by pulling the
cervix up over the presenting part
of the fetus
Second, the fluid-filled membranes
press against the cervix
As dilation begins there is large
amount of vaginal secretions
(show) because the last of the
operculum or mucus plug in the
cervix is dislodged and capillaries
in the cervix rupture
STAGES OF LABOR
1. Stage 1 (stage of dilatation) – begins
with the true labor pains and ends when
the cervix has reached full dilatation
Nursing Care:
Stay with woman; provide constant
support
Reminds, reassures and encourages
woman to reestablish breathing
patterns and concentration as needed
Prompts partial respirations if woman
begins to push prematurely accepts
woman inability to comply with
instructions
Keeps woman aware of progress
4 Phases:
Latent Phase
Begins at the regularly
perceived uterine contractions
and ends when rapid cervical
dilatation begins
Contractions are mild and short
lasting 20-40 seconds
Cervix dilates from 0-3cm
6 hours in nullipara
4.5 hours in multipara
Nursing Care:
- Assists woman to cope with
contraction
- Helps to concentrate in
breathing techniques
- Assists into comfortable
position
- Informs woman of the
progress of labor
- Explains procedure and
routines
- Offer fluids, ice chips, food
as ordered
Active Phase
Dilatation increases from 4 – 7
cm
Contraction lasts 40-60 sec and
occur every 3-5 minutes
3 hours in nullipara
2 hours in multipara
Show and spontaneous rupture
of membranes may occur
Nursing Care:
- Finds assessment
techniques between
contractions
- Assists with frequent
position change
- Applies counter pressure to
sacrococcygeal area
- Encourages and praises
- Keeps woman aware of
progress
- Check bladder and
encourages voiding
- Gives oral care
Transition Phase
Contractions reached their peak
of intensity occurring every 2-3
minutes with duration of 6090sec
Maximum dilatation 8-10cm
Complete cervical effacement
Woman experiences intense
discomfort accompanied by
nausea and vomiting
Woman may also experience a
feeling of loss of control,
anxiety, panic or irritability
2. Stage 2 (Stage of Expulsion) – the
period from full dilatation to birth of the
infant
Contractions change from the
characteristic crescendodecrescendo pattern to
overwhelming uncontrollable urge
to push or bear down with each
contraction as if to move her
bowels
Woman perspire and the blood
vessels in her neck may become
distended
Crowning takes place
The need to push become
intense and the woman cannot
stop herself
6 Cardinal Movements of the
Mechanism of labor
o Descent – downward movement of
the biparietal diameter of the fetal
head to within the pelvic inlet
- full descent occurs and the
fetal head extrudes beyond
the dilated cervix and
touches the posterior
vaginal floor
o Flexion – the head bends forward
onto the chest, making the
smallest anteroposterior diameter
o Internal rotation – the occiput
rotates until it is superior, or just
below the symphysis pubis,
bringing the head into the best
relationship to the outlet of the
pelvis
o Extension – as the occiput is born,
the back of the neck stops beneath
the pubic arch and acts as a pivot
for the rest of the head. The head
extends, and the foremost parts of
the head, the face and chin are
born.
o External Rotation – almost
immediately after the head of the
infant is born, the head rotates
(from the anteroposterior position
it assumed to enter the outlet)
back to the diagonal or transverse
position of the early part of labor
o Expulsion – the rest of the baby is
born easily and smoothly because
of its smaller part size. The end of
the pelvic division of labor.
Nursing Care:
Put both legs at the same
time when positioning to the
lithotomy position
Instruct mother to push as
fetal head crowns. If
hyperventilation occurs, let patient
breathe into a brown paper or a
cupped hand.
3. Stage 3 (Placental Stage) – begins
from the delivery of the baby up to
the delivery of the placenta
2 Phases:
a. Placental Separation
Signs:
- Lengthening of the cord
- Sudden gush of blood
- Change of shape of the
uterus
b. Placental Expulsion
- Brandt Andrew’s Maneuver – tract
the cord slowly, winding it around the
clamp until placenta spontaneously
comes out rotating it slowly so that no
membranes are left
Nursing Care:
Don’t hurry the expulsion of the
placenta, just watch for the signs of
placental separation
Take note of the time of placental
delivery
Inspect for the completeness of the
placenta
Palpate the uterus to determine
degree of contraction. If relaxed,
massage gently and apply ice cap
Inspect for lacerations
Types of Placental Presentation
Schultze’s – appearing shiny and
glittering from the fetal
membranes
Duncan – it looks raw, dirty,
meaty, red and irregular
4. Stage 4 (Puerperium Stage) – first 4
hours after delivery of placenta
Degrees of Perineal Lacerations:
1. First Degree – skin and superficial to
muscle
2. Second Degree – muscles of the
perineum
3. Third Degree – continues to anal
sphincter
4. Fourth Degree – involves the anterior
anal wall
Episiotomy – incision made to the
perineum to enlarge the vaginal opening
for easy delivery
Types:
a. Midline/Median
b. Mediolateral
c. Lateral
Advantages:
1. Enlarging of the vaginal opening
2. Shortening of the second stage of
labor
3. Minimizing the stretching of the
perineal muscle
4. Preventing perineal tearing
Fetal Monitoring – periodic change or
fluctuation in FHR occur in response to
contractions and the fetal movements
are described in terms of accelerations or
decelerations
- done through intermittent
auscultation
- electronic monitoring
1. External – transabdominal,
noninvasive, monitors uterine contraction
and FHR; client needs to decrease extraabdominal movements
2. Internal – membranes must be
ruptured, cervix sufficiently dilated and
presenting part; invasive procedure;
continuous monitoring
- results of monitoring: normal FHR
120-160; must obtain a baseline
Acceleration – 15 bpm rise above
baseline followed by return; usually in
response to fetal movement or
contractions; indicates fetal well-being
Deceleration – fall below baseline lasting
15 seconds or more, followed by a return:
a. Early Deceleration – are periodic
decreases in the FHR resulting from
pressure on the fetal head during
contraction (head compression)
b. Late Deceleration – indicative of
fetal hypoxia because of deficient
placental perfusion (uteroplacental
insufficiency)
c. Variable Deceleration – occurs at
unpredictable times during contractions
and indicates cord compression
Anesthesia – encompasses analgesia
amnesia, relaxation and reflex activity. It
abolishes pain perception by interrupting
the nerve impulses to the brain. The loss
of sensation may be partial incomplete,
sometimes with loss of consciousness.
Analgesia – refers to the alleviation of the
sensation of pain or in the raising of the
threshold for pain perception without loss
of consciousness
