Dr. Areefa Al Bahri

1
Dr. Areefa Al Bahri
Ch. 5 The Birth Experience
Physiological, psychological, and
emotional changes that take place during
pregnancy help to prepare the woman for labor and
birth. Near the end of the pregnancy, the fetus
continues to develop physiological abilities that
facilitate successful adaptation for the
transition from in utero life to the outside
environment.
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The Process of Labor and Birth

• A number of forces affect the progress of labor
  and help to bring about childbirth. These
  critical factors are often
• referred to as the Ps of labor
• Powers (physiological forces)
• Passageway (maternal pelvis)
• Passenger (fetus and placenta)
• Passageway Passenger and their relationship
• (engagement, attitude, position)
• 5. Psychosocial influences (previous
  experiences, emotional status)

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POWERS The powers are the physiological forces of
labor and birth that include the uterine
contractions and the maternal pushing efforts.
The uterine muscular contractions, primarily
responsible for causing cervical effacement and
dilation, also move the fetus down toward the
birth canal during the fi rst stage of labor.
Uterine contractions are considered the primary
force of labor. Once the cervix is fully dilated,
the maternal pushing efforts serve as an
additional force. During the second stage of
labor, use of the maternal abdominal muscles for
pushing (the secondary force of labor) adds to
the primary force to facilitate childbirth.
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Characteristics of Uterine Contractions Contractio
ns are a rhythmic tightening of the uterus that
occurs intermittently. Over time, this action
shortens the individual uterine muscle fi bers
and aids in the process of cervical effacement
and dilation, birth, and postpartal involution
(the reduction in uterine size after birth). Each
contraction consists of three distinct
components the increment (building of the
contraction), the acme (peak of the contraction)
and the decrement (decrease in the contraction).
Between contractions, the uterus normally returns
to a state of complete relaxation. This rest
period allows the uterine muscles to relax and
provides the woman with a short recovery period
that helps her to avoid exhaustion. In addition,
uterine relaxation between contractions is
important for fetal oxygenation as it allows for
blood fl ow from the uterus to the placenta to be
restored.
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The lower uterine segment becomes thin-walled and
passive. The boundary between the upper lower
uterine segments becomes marked by a ridge on the
inner uterine surface, known as the
physiological retraction ring. With each
contraction, the uterus elongates. Elongation
causes a straightening of the fetal body so that
the upper body is pressed against the fundus and
the lower, presenting part is pushed toward the
lower uterine segment and the cervix. The
pressure exerted by the fetus is called the fetal
axis pressure. As the uterus elongates, the
longitudinal muscle fibers are stretched upward
over the presenting part. This force, along with
the hydrostatic pressure of the fetal membranes,
causes the cervix to dilate (open).
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The coordinated efforts of the contractions help
to bring about effacement and dilatation of the
cervix. Effacement is the process of shortening
and thinning of the cervix. As contractions
occur, the cervix becomes progressively shorter
until the cervical canal eventually disappears.
The amount of cervical effacement is usually
expressed as a percentage related to the length
of the cervical canal, as compared to a non
effaced cervix. For example, if a cervix has
thinned to half the normal length of a cervix it
is considered to be 50 effaced. Dilation is the
opening and enlargement of the cervix that
progressively occurs throughout the first stage
of labor. Cervical dilation is expressed in
centimeters and full dilation is approximately 10
cm. With continued uterine contractions, the
cervix eventually opens large enough to allow the
fetal head to come through. At this point, the
cervix is considered fully dilated or completely
dilated and measures 10 cm.
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Maternal Pushing Efforts After the cervix has
become fully dilated, the laboring woman usually
experiences an involuntary bearing
down sensation that assists with the expulsion
of the fetus. At this time, the woman can use her
abdominal muscles to aid in the expulsion. It is
important to remember that the cervix must be
fully dilated before the patient is encouraged to
push. Bearing down on a partially dilated cervix
can cause cervical edema and damage and adversely
affect the progress of the labor. For most women,
the urge to bear down generally occurs when the
fetal head reaches the pelvic fl oor. Women who
have a strong urge to push often do so more
effectively than women who force themselves to
push without experiencing any sensations of
pressure.
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PASSAGEWAY The passageway consists of the
maternal pelvis and the soft tissues. The bony
pelvis through which the fetus must pass is
divided into three sections the inlet, midpelvis
(pelvic cavity), and outlet. Each of these pelvic
components has a unique shape and dimension
through which the fetus must maneuver to be born
vaginally. In human females, the four classic
types of pelvis are the gynecoid, android,
platypelloid, and anthropoid.
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PASSENGER The passenger is referred to as the
fetus and the fetal membranes. In the majority
(96) of pregnancies, the fetus presents in a
head-fi rst position. The fetal skull, usually
the largest body structure, is also the least
flexible part of the fetus. However, because of
the sutures and fontanels, there is some
flexibility in the fetal skull. These structures
allow the cranial bones the capability of
movement and they overlap in response to the
powers of labor. The overlapping or overriding of
the cranial bones is called molding.
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The fetal skull, or cranium, consists of three
major components the face, the base of the
skull, and the vault of the cranium (roof). The
facial bones and the cranial base are fused and
fixed. The cranial base is made up of two
temporal bones. The cranial vault is composed of
five bones two frontal bones, two parietal
bones, and the occipital bone. These bones, which
are not fused, meet at the sutures. The sutures
of the fetal skull are composed of strong but
flexible connective tissue that fills the spaces
that lie between the cranial bones.
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The sagittal suture lies between the parietal
bones and runs in an anteroposterior direction
between the fontanels, dividing the head into a
right and a left side. The lambdoidal suture
extends from the posterior fontanel and separates
the occipital bones from the parietal bones. The
coronal sutures are located between the frontal
and parietal bones. They extend from the anterior
fontanel laterally and separate the parietal from
the frontal bones. The frontal (mitotic) suture
lies between the frontal bones and extends from
the anterior fontanel to the prominence between
the eyebrows. Two membrane-fi lled spaces are
present where the suture lines meet. These spaces
are referred to as the anterior and posterior
fontanels. The anterior fontanel is the larger of
the two and measures approximately 0.8 1.2 inch
(2 3 cm). It is diamond shaped and is positioned
where the sagittal, frontal, and coronal
sutures intersect. The anterior fontanel remains
open until approximately 18 months of age to
allow normal brain growth to occur. The posterior
fontanel is triangular in shape and is much
smaller than the anterior fontanel. It measures
approximately 0.8 inch (2 cm) at its widest
point. The posterior fontanel is positioned where
the lambdoidal and sagittal sutures meet. Shaped
like a small triangle, it closes at approximately
6 to 8 weeks after birth.
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Fetal Presentation The fetal presentation refers
to the fetal part that enters the pelvic inlet
first and leads through the birth canal during
labor. The fetal presentation may be cephalic,
breech, or shoulder. The part of the fetal body
first felt by the examining finger during a
vaginal examination is the presenting part. The
presenting part is determined by the fetal lie
and attitude. CEPHALIC PRESENTATION fetal head
will be first to come into contact with the
maternal cervix. Cephalic presentations occur in
approximately 95 of pregnancies. There are four
types of cephalic presentations Vertex. The
fetal head presents fully flexed. This is
the most frequent and optimal presentation as it
allows the smallest suboccipitalbregmatic
diameter to present. It is called a vertex
presentation. Military. In the military
position, the fetal head presents in a neutral
position, which is neither flexed nor extended.
The occipitofrontal diameter presents to the
maternal pelvis and the top of the head is the
presenting part. Brow. In the brow position, the
fetal head is partly extended. This is an
unstable presentation that converts toFace. Face
presentation. the fetal head is fully extended.
The submentobregmatic diameter presents to the
maternal pelvis and the face is the presenting
part
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The following advantages are associated with a
cephalic presentation The fetal head is
usually the largest part of the infant. Once the
fetal head is born, the rest of the body usually
delivers without complications. The fetal head
is capable of molding. There is sufficient time
during labor and descent for molding of the fetal
head to occur. Molding helps the fetus to
maneuver through the maternal birth passage.
The fetal head is smooth and round, which is the
optimal shape to apply pressure to the cervix and
aid in dilation. Other presentations (e.g.,
breech, shoulder) are associated with difficult,
prolonged labor and often require cesarean
births. They are called malpresentations.
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BREECH PRESENTATION A breech presentation occurs
when the fetal buttocks enter the maternal pelvis
first. Breech presentations occur in
approximately 3 of births and are classified
according to the attitude of the fetal hips and
knees. Breech presentations are more likely to
occur in preterm births or in the presence of a
fetal abnormality such as hydrocephaly (head
enlargement due to fluid) that prevents the head
from entering the pelvis. They are also
associated with abnormalities of the maternal
uterus or pelvis. Since many factors can
compromise the normal labor and birth process
associated with breech presentations, delivery is
usually accomplished via cesarean section. There
are three types of breech presentations Frank.
The frank breech is the most common of all breech
presentations Complete (Full). The complete, or
full, breech position is the same as the flexed
position with the fetal buttocks presenting
first. The legs are typically flexed. Footling.
In the footling breech position, one or both
of the fetal leg(s) are extended with one foot
(single footling) or both feet (double
footling) presenting first into the maternal
pelvis.
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• Several disadvantages are associated with a
  breech presentation
• An increased risk for umbilical cord prolapsed
  because the presenting part may not be covering
  the cervix (i.e., footling breech).
• 2. The presenting part (buttocks, feet) is not as
  smooth and hard as the fetal head and is less
  effective in dilating the cervix.
• 3. Once the fetal body (abdomen) is delivered,
  the umbilical cord can become compressed.
• Rapid delivery may be difficult since the fetal
  head is usually the largest body part and in this
  situation, there is no time to allow for molding.
  In response to adverse outcomes that have been
  associated with vaginal breech births, the
  American College of Obstetricians and
  Gynecologists (ACOG, 2006) has published a
  Committee Opinion concerning planned breech
  deliveries.

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SHOULDER PRESENTATION The shoulder presentation
is a transverse lie (Fig. below). This
presentation is rare and occurs in fewer than 1
of births. When a transverse lie is present, the
maternal abdomen appears large from side to side,
rather than up and down. In addition, the woman
may demonstrate a lower than expected (for the
gestational age) fundal height measurement.
Although the shoulder is usually the presenting
part, the fetal arm back, abdomen, or side may
present in a transverse lie. This presentation
occurs most often with preterm birth, high
parity, prematurely ruptured membranes,
hydramnios, and placenta previa. It is important
for the nurse to promptly identify a transverse
lie or shoulder presentation since the infant
will almost always require a cesarean birth.
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Station Station refers to the level of the
presenting part in relation to the maternal
ischial spines. In the normal female pelvis, the
ischial spines represent the narrowest diameter
through which the fetus must pass. The ischial
spines is a landmark to identify station zero. To
visualize the location of station zero, an
imaginary line may be drawn between the ischial
spines. Engagement has occurred when the
presenting part is at station zero. When the
presenting part lies above the maternal ischial
spines, it is at a minus station. Therefore, a
station of minus 5 (5) cm indicates that the
presenting part is at the pelvic inlet. Positive
numbers indicate that the presenting part has
descended past the ischial spines. During labor,
the presenting part should continue to descend
into the pelvis, indicating labor progress. As
labor advances and the presenting part descends,
the station should also progress to a numerically
higher positive station. If the station does not
change in the presence of strong, regular
contractions, this finding may indicate a problem
with the relationship between the maternal pelvis
and the fetus (cephalopelvic disproportion).
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Position Position refers to the location of a
fixed reference point on the fetal presenting
part in relation to a specific quadrant of the
maternal pelvis (Fig. 12-10). The presenting part
can be right anterior, left anterior, right
posterior, and left posterior. These four
quadrants designate whether the presenting part
is directed toward the front, back, right, or
left of the passageway.
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Passageway (passenger) The passageway and the
passenger have been identified as two of the
factors that affect labor. The next P is the
relationship between the passageway (maternal
pelvis) and the passenger (fetus and membranes).
The nurse assesses the relationship between the
two when determining the engagement, station, and
fetal position. Engagement Engagement is said to
have occurred when the widest diameter of the
fetal presenting part has passed through the
pelvic inlet. In a cephalic presentation, the
largest diameter is the biparietal in breech
presentations, it is the intertrochanteric
diameter. Engagement can be determined by
external palpation or by vaginal examination. In
primigravidas, engagement usually occurs
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PSYCHOSOCIAL INFLUENCES The first four Ps
discussed address the physical forces of labor.
The last P (psychosocial influences)
acknowledges the many other critical factors that
have an effect on parents such as their readiness
for labor and birth, level of educational
preparedness, previous experience with labor and
birth, emotional readiness, cultural influences,
and ethnicity. Transition into the maternal role,
and most likely, into the paternal role as well,
is facilitated by a positive childbirth
experience. A number of internal and external
influences can affect the womans
psychological well-being during labor and birth.
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Culturally oriented views of childbirth help to
shape the womans expectations and ongoing
perceptions of the birth experience. The nurses
understanding of the cultural values and
expectations attached to childbirth provide a
meaningful framework upon which to plan and
deliver sensitive, appropriate care. Cultural
considerations for the laboring woman encompass
many elements of the birth experience including
choice of a birth support person strategies for
coping with contractions, pain expression and
relief and food preferences. Signs and Symptoms
of Impending Labor Before the onset of labor, a
number of physiological changes occur that signal
the readiness for labor and birth. These changes
are usually noted by the primigravid woman at
about 38 weeks of gestation. In multigravidas,
they may not take place until labor begins. It is
important for nurses to empower pregnant women
and their families by teaching them about the
signs and symptoms of impending labor. Providing
guidelines about when to contact the health care
provider or come to the birth facility helps to
demystify the sometimes confusing events that
surround birth and lessen the anxieties that can
accompany the onset of labor.
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LIGHTENING At about 38 weeks in the primigravid
pregnancy, the presenting part (usually the fetal
head) settles downward into the pelvic cavity,
causing the uterus to move downward as well. This
process, called lightening, marks the beginning
of engagement. This downward settling of the
uterus may decrease the upward pressure on the
diaphragm and result in easier breathing. The
downward settling may also lead to the following
maternal symptoms Leg cramps or pains
Increased pelvic pressure Increased urinary
frequency Increased venous stasis, causing
edema in the lower extremities Increased
vaginal secretions, due to congestion in
the vaginal mucosa
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BRAXTON-HICKS CONTRACTIONS As the pregnancy
approaches term, most women become more aware of
irregular contractions called Braxton-Hicks
contractions. As the contractions increase in
frequency (they may occur as often as every 10 to
20 minutes), they may be associated with
increased discomfort. Braxton-Hicks contractions
are usually felt in the abdomen or groin region
and patients may mistake them for true labor. It
is believed that these contractions contribute to
the preparation of the cervix and uterus for the
advent of true labor. Braxton-Hicks contractions
do not lead to dilation or effacement of the
cervix, and thus are often termed false
labor. CERVICAL CHANGES In the non pregnant
woman, the cervix is normally rigid. In
preparation for passage of the fetus, the cervix
undergoes many physiological changes. The cervix
softens (cervical ripening), stretches, and
thins, and eventually is taken up into the lower
segment of the uterus. This softening and
thinning is called cervical effacement.
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BLOODY SHOW During pregnancy the cervix is
plugged with mucus. The mucus plug acts as a
protective barrier for the uterus and its
contents throughout the pregnancy. As the cervix
begins to soften, stretch, and thin through
effacement, there may be rupture of the small
cervical capillaries. The added pressure created
by engagement of the presenting part may lead to
the expulsion of a blood mucus plug, called
bloody show. Its presence often indicates that
labor will begin within 24 to 48 hours. Late in
pregnancy, vaginal examination that involves
cervical manipulation may also produce a bloody
discharge that can be confused with bloody show.
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Rupture Of The Membranes About 12 of pregnant
women experience spontaneous rupture of the
amniotic sac (ruptured membranes or ruptured
bag of waters) prior to the onset of labor. In
the majority of pregnancies, the amniotic
membranes rupture once labor is well established,
either spontaneously or by amniotomy, the
artificial rupture of the membranes by the
primary care provider. Rupture of the membranes
is a critical event in pregnancy. If the
membranes do rupture at home, the woman should be
taught to immediately contact the birthing center
who will advise her to report for an examination.
It is important for the woman to note the
color, amount, and odor of the amniotic fluid.
The fluid should be clear and odorless. A yellow
green tinged amniotic fluid may indicate
infection or fetal passage of meconium and this
finding always signals the need for further
assessment and fetal heart rate monitoring.
Urinary incontinence (frequently associated with
urgency, coughing, and sneezing) is sometimes
confused with ruptured membranes. The presence of
amniotic fluid can be confirmed by a Nitrazine
tape test or by a fern test.
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First Stage of Labor This stage begins with the
onset of regular uterine contractions and ends
with complete dilation of the cervix. woman may
not always recognize when true labor actually
begins. The first stage of labor is most often
the longest stage and its duration can vary
considerably among women. The first stage of
labor is divided into three distinct phases
latent, active, and transition. Factors such as
analgesia, maternal and fetal position, the
womans body size and her level of physical
fitness can also affect the length of labor.
LATENT PHASE Labor pains are often initially
felt as sensations similar to painful menstrual
cramping and are usually accompanied by low back
pain. Contractions during this phase are
typically about 5 minutes apart, last 30 to 45
seconds, and are considered to be mild. During
the latent phase cervical effacement and early
dilation (0 to 3 cm) occurs. The latent phase of
labor can last as long as 10 to 14 hours as the
contractions are mild and cervical changes occur
slowly.
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ACTIVE PHASE The active phase of labor is
characterized by more active contractions. The
contractions become more frequent (every 3 to 5
minutes), last longer (60 seconds), and are of a
moderate to strong intensity. During the active
labor phase, the woman becomes more focused on
each contraction and tends to draw inward in an
attempt to cope with the increasing demands of
the labor. Cervical dilation during this phase
advances more quickly as the contractions are
often more efficient. While the length of the
active phase is variable, nulliparous women
generally progress at an average speed of 1 cm of
dilation per hour and multiparas at 1.5 cm of
cervical dilation per hour. TRANSITION
PHASE The transition phase is the most intense
phase of labor. Transition is characterized by
frequent, strong contractions that occur every 2
to 3 minutes and last 60 to 90 seconds on
average. Fortunately, this phase often does not
take long because dilation usually progresses at
a pace equal to or faster than active labor (1
cm/hr for a nullipara and 1.5 cm/hr for a
multipara).
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Assessment of the Fetus During Labor and
Birth Fetal assessments include the
identification of fetal position and
presentation, and the evaluation of the fetal
status. Nurses use a variety of assessment
techniques including observation, palpation, and
auscultation. When assessing a woman in labor,
the nurse is able to use observation and
interview skills from the moment the woman comes
through the door. Astute observation assists the
nurse in assessing the patients level of pain,
her coping abilities
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Baseline Fetal Heart Rate The normal baseline
fetal heart rate at term is 110 to 160 beats per
minute (bpm). There are two abnormal variations
of the baseline tachycardia (baseline above 160
bpm) and bradycardia (baseline below 110
bpm). TACHYCARDIA. Tachycardia is generally
defi ned as a sustained baseline fetal heart rate
greater than 160 beats per minute for a duration
of 10 minutes or longer. A number of conditions
are associated with fetal tachycardia Fetal
hypoxia The fetus attempts to compensate for
reduced blood flow by increasing sympathetic
stimulation of the central nervous system (CNS).
Maternal fever Maternal medications Both
parasympathetic drugs (i.e., atropine,
scopolamine) and beta-sympathetic drugs
(tocolytic drugs used to halt contractions) can
have a stimulant effect and increase the fetal
heart rate. Infection uterine infection
(amnionitis) Fetal anemia In response to a
decrease in hemoglobin, the FHR increases to
compensate and improve tissue metabolism.
Maternal hyperthyroidism Thyroid-stimulating
hormone (TSH) may cross the placenta and
stimulate the fetal heart rate (Tucker, 2004).
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• BRADYCARDIA
• Bradycardia is defined as baseline FHR of less
  than 110 to 120 bpm. Fetal bradycardia may be
  associated with
• Late hypoxia Myocardial activity becomes
  depressed and lowers the fetal heart rate.
• Medications Beta-adrenergic blocking drugs
  (e.g., propanolol Inderal).
• Maternal hypotension
• Prolonged umbilical cord compression
• Bradyarrhythmias With complete heart block,
  the FHR
• baseline is often as low as 70 to 90 bpm.

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Variability Variability of the FHR is manifested
by fluctuations in the baseline fetal heart rate
observed on the fetal monitor. The pattern
denotes an irregular, changing FHR rather than a
straight line that indicates few changes in the
rate. The variability of the FHR is a result of
the interplay between the fetal sympathetic
nervous system, which assists to increase the
heart rate and the parasympathetic nervous
system, which acts to decrease the heart
rate. The absence of or undetected variability
is considered non-reassuring. FHR variability
is indicative of an adequately oxygenated
neurological pathway in which impulses are
transmitted from the fetal brain to the cardiac
conduction system (Fox, Kilpatrick, King,
Parer, 2000). Conversely, the absence of
variability may indicate normal variations such
as fetal sleep (the sleep state should not last
longer than 30 minutes), a response to certain
drugs that depress the CNS, such as analgesics
(meperidine Demerol, tranquilizers (diazepam
Valium),
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ACCELERATIONS An acceleration is defined as an
increase in the FHR of 15 bpm above the fetal
heart baseline that lasts for at least 15 to 30
seconds. Accelerations are considered a sign of
fetal well-being when they accompany fetal
movement. Thus, when a fetus is active in utero,
accelerations are normally present. When
contractions are present, accelerations are often
noted as a response to the contraction.
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DECELERATIONS Decelerations are defined as any
decrease in FHR below the baseline FHR.
Decelerations are further defined according to
their onset and are characterized as early,
variable, and late. Early Decelerations Early
decelerations are characterized by a deceleration
in the FHR that resembles a mirror image to the
contraction. Therefore, the onset of the
deceleration begins near the onset of the
contraction, and the FHR returns to baseline by
the end of the contraction. Early decelerations
are usually repetitive and are commonly observed
during active labor and descent of the fetus
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Variable Decelerations Variable decelerations, as
the name implies, are decelerations that are
variable in terms of their onset, frequency,
duration, and intensity. The decrease in FHR
below the baseline is 15 bpm or more, lasts at
least 15 seconds, and returns to the baseline in
less than 2 minutes from the time of onset
(NICHD, 1997) (Fig. 12-19). The deceleration is
unrelated to the presence of uterine
contractions. Variable decelerations are thought
to be a result of umbilical cord compression.
Thus, the degree by which the cord is compressed
(partially versus completely) can affect the
severity of the deceleration. The American
College of Obstetricians and Gynecologists (ACOG,
2005) classifies variable decelerations as
significant when the FHR falls below 70 bpm and
lasts longer than 60 seconds. In addition, the
Society of Obstetricians and Gynaecologists of
Canada (SOGC, 2005) concurs and further identifi
es non-reassuring or atypical variable
decelerations as
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Late Decelerations This type of deceleration does
not resolve until after the contraction has
ended. Late decelerations indicate the presence
of uteroplacental insufficiency, a decline in
placental function. a decrease in blood flow
from the uterus to the placenta results in fetal
hypoxia and late decelerations. Late
decelerations require prompt attention and
reporting. The longer the late decelerations
persist, the more serious they become. For
example, late decelerations in the presence of an
oxytocin infusion may signal a need to
immediately discontinue the oxytocin infusion,
especially if uterine hyperstimulation is
suspected. Nursing interventions that should be
implemented immediately include reporting the
late decelerations, changing the maternal
position, discontinuing the oxytocin
infusion, increasing the intravenous fl uids, and
administering oxygen by mask.
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The Cardinal Movements The cardinal movements, or
mechanisms of labor, have been used to describe
how the fetus (in a vertex presentation) passes
through the birth canal and the positional
changes required to facilitate birth (Fig.
12-23). The cardinal movements are presented in
the order in which they occur. Descent Four
forces facilitate descent, which is the
progression of the fetal head into the maternal
pelvis (1) pressure of the amniotic fluid (2)
direct pressure of the uterine fundus on the
fetal breech (3) contraction of the maternal
abdominal muscles and (4) extension and
straightening of the fetal body. The fetal head
enters the maternal inlet in the occiput
transverse or the oblique position because the
pelvic inlet is widest from side to side. The
sagittal suture is equidistant from the maternal
symphysis pubis and sacral promontory. The degree
of fetal descent is measured by stations.
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Flexion Flexion occurs as the fetal head descends
and comes into contact with the soft tissues of
the pelvis, the muscles of the maternal pelvic
floor, and the cervix. The resistance encountered
with these structures causes the fetal chin to
flex downward onto the chest. This position
allows the smallest fetal diameters to enter the
maternal pelvis.
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Internal Rotation To fit into the maternal pelvic
cavity, which is widest in the anteroposterior
diameter, the fetal head must rotate.
Extension As the fetal head passes under the
maternal symphysis pubis, it meets with
resistance from the pelvic floor. The head pivots
and extends with each maternal pushing effort.
The head is born in extension as the occiput
slides under the symphysis and the face is
directed toward the rectum. The fetal brow, nose,
and chin then emerge. Restitution Internal
rotation causes the fetal shoulders to enter the
maternal pelvis in an oblique position. After the
head is delivered in the extended position, it
rotates briefly to the position it occupied when
it was engaged in the inlet. This movement is
termed restitution. The 45-degree turn of the
fetal head facilitates realignment with the long
axis of the body.
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External Rotation As restitution continues, the
shoulders align in the anteroposterior diameter,
causing the head to continue to turn farther to
one side (external rotation). The fetal trunk
moves through the pelvis with the anterior
shoulders descending first. Expulsion After
external rotation, maternal pushing efforts bring
the anterior shoulder under the symphysis pubis.
Lateral flexion of the shoulder and head occurs
and the anterior, then posterior, shoulder is
born. Once the shoulders are delivered, the rest
of the body quickly follows.
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Second Stage of Labor
The second stage of labor commences with full
dilation of the cervix and ends with the birth of
the infant. Often the woman or nurse may suspect
that the woman has entered the second stage of
labor because of the patients urge to push or
the presence of involuntary bearing down efforts.
The contractions often remain very similar to
those experienced during the transition stage.
It is important to encourage the patient to
rest between pushing in order to maintain her
energy throughout the second stage. The duration
of the second stage is variable and may be
influenced by several factors such as parity the
type and amount of analgesia or anesthesia
administered the frequency, intensity, and
duration of contractions maternal efforts in
pushing, and the support the patient receives.
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Achieving A Position Of Comfort
Positions such as squatting and kneeling may also
help to increase the dimensions of the maternal
pelvis. Assuming a hands and knees position or
leaning over a table or chair helps to take
pressure off the maternal spine and often reduces
backache commonly associated with a fetal
occipitalposterior position
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Preparation For The Birth As the fetus descends,
the woman experiences an increasing urge to bear
down due to pressure of the fetal head. As the
fetal head progresses downward, the perineum
begins to stretch, thin out, and move anteriorly.
The amount of bloody show may increase at this
time and the labia begin to part with each
contraction. The fetal head, which may be
observable at the vaginal. Crowning, which means
that birth is imminent, occurs when the fetal
head is encircled by the vaginal introitus. The
woman may also feel intense pressure in the
rectum and a need to evacuate her bowels. Some
women may feel as though they are losing control
and a variety of emotions (e.g., irritability,
fear, embarrassment, and helplessness) may be
displayed.
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EPISIOTOMY Episiotomy is a surgical incision of
the perineum that is performed to enlarge the
vaginal orifice during the second stage of labor
(Carroli Belizan, 2006). At that time, many
physicians routinely performed episiotomies based
on the belief that surgical enlargement of the
vaginal opening would prevent complications such
as fetal trauma, and severe lacerations, and
later maternal problems such as cystocele,
rectocele, dyspareunia, and uterine prolapse. In
studies where episiotomy had been performed for
medical indications, the results demonstrated
positive benefits. The use of episiotomy for
medical indications, which include
instrumentation during birth (forceps or vacuum),
a need to expedite the birth (evidence of fetal
compromise), or in the event of maternal
exhaustion.
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Two different methods are used for the
episiotomy. The most common method is the midline
or median episiotomy. An incision is made from
the vaginal opening downward toward the rectum. A
midline episiotomy is easily repaired, heals
quickly, and is associated with less
postoperative pain than a mediolateral
episiotomy. However, the primary disadvantage of
a midline episiotomy is the risk of third-
and fourth-degree lacerations with extension
through the rectal sphincter.
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Third Stage of Labor The third stage of labor is
the period of time from the birth of the baby to
the complete delivery of the placenta. This stage
usually lasts 5 to 10 minutes, and may last up to
30 minutes. Once the baby is born, the uterine
cavity immediately becomes smaller. The change in
the interior dimension of the uterus results in a
reduction in the size of the placental attachment
site.
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The following clinical indicators signal that
separation of the placenta from the uterus has
occurred The uterus becomes spherical in
shape. The uterus rises upward in the abdomen
due to the descent of the placenta into the
vagina. The umbilical cord descends further
through the vagina. A gush of blood occurs once
the placenta detaches from the uterus. As the
placenta separates from the uterine wall, it is
important that the uterus continues to contract.
The contractions minimize the bleeding that
results from the open blood vessels left at the
placental attachment site. Failure of the uterus
to contract adequately with separation of the
placenta can result in excessive blood loss or
hemorrhage. To enhance the uterine contractions
after expulsion of the placenta, oxytocic
medications are often given. Oxytocin is
administered either by the intravenous (IV) route
or by intramuscular (IM) injection.
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NURSING CARE OF THE MOTHER DURING THE THIRD STAGE
OF LABOR After the birth of the infant, the nurse
observes for signs that the placenta has
separated from the wall of the uterus. The uterus
is palpated to determine the rise upward as well
as the characteristic change in shape from one
resembling a disk to that of a globe. The nurse
may ask the woman to push again, to facilitate in
the delivery of the placenta. If 30 minutes have
elapsed from completion of
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the second stage of labor and the placenta has
not yet been expelled, it is considered to be
retained. (See Chapter 14 for further
discussion.) Oxytocic medications such as Pitocin
and Syntocinon are often administered at the time
of the delivery of the placenta. These drugs are
used to stimulate uterine contractions, thereby
minimizing the bleeding from the
placental attachment site and reducing the risk
of postpartum hemorrhage.
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The nurse administers oxytocic medications accordi
ng to institutional protocol. If a peripheral
intravenous infusion has been established,
oxytocin 10 to 20 units may be added to the
intravenous infusion. If no intravenous infusion
is present, 10 units of oxytocin may
be administered intramuscularly. In situations
where there is excessive blood loss, the
physician may order up to 40 units of oxytocin
per liter of intravenous infusion fl uid. Other
medications such as methylergonovine
maleate (Methergine) or carboprost tromethamine
(Hemabate) may be given intramuscularly to
control blood loss. During this time the nurse
continues to assess the volume of blood loss and
monitor the patients vital signs, paying
close attention to the blood pressure and heart
rate. Once the placenta has been delivered, the
nurse carefully examines it to ensure that all
cotyledons are intact (Fig. 12-26). If any part
of the placenta is missing, the nurse immediately
reports this fi nding to the attending physician.
Because retained placental fragments can
contribute to postpartum hemorrhage or infection,
the physician may perform a manual exploration of
the uterus to remove any remaining placental
tissue.
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Immediate Nursing Care of the Newborn Once the
newborn has been born, the primary care
provider (physician or certifi ed nurse midwife)
places the infant on the mothers abdomen (if the
infant is stable), in a modifi ed Trendelenburg
position. This immediate contact between mother
and newborn provides reassurance to the mother
regarding the overall well-being of the baby, and
begins the attachment process. Birth signals the
transition from fetus to newborn. Several
physiological adaptations must occur to
facilitate the adjustment of the newborn to the
extrauterine environment. Of primary importance
is the initiation of the newborns respirations,
a process that results in the replacement of
fetal lung fl uid with air. In most
situations, the actions of drying the newborn and
performing nasopharyngeal suctioning, if needed,
provide adequate stimulation to initiate the
newborns respiratory effort. While respirations
are being established, the newborns cardiovascula
r system is also undergoing major adaptations to
allow the fl ow of deoxygenated blood into
the lungs for gas exchange. Fetal circulation
transitions to neonatal circulation after closure
of the ductus arteriosus, the foramen ovale, and
the ductus venosus. (See Chapter 17 for further
discussion of the physiological transitions in
the newborn.) The modifi ed Trendelenburg
position facilitates the drainage of mucus from
the newborns nasopharynx and trachea. The nurse
suctions the newborns nose and mouth with a bulb
syringe as needed. Preventing heat loss in the
neonate constitutes an important nursing
role. Before the infant is placed on the mothers
abdomen, the nurse dries the infant, discards the
wet linens, and applies warm blankets.
Skin-to-skin contact between the mother and baby
also helps to maintain the newborns temperature.
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THE APGAR SCORING SYSTEM The nurse assesses this
transition stage after one minute and again after
5 minutes, using the Apgar Scoring
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HEART RATE. The priority assessment of the
newborn is the heart rate. On auscultation or
palpation, the nurse recognizes an absent heart
rate or heart rate less than 100 bpm as a signal
for resuscitation. RESPIRATORY EFFORT. The
newborns vigorous cry best indicates adequate
respiratory effort, the next most
important assessment after birth. A weak or
absent cry is a signal for intervention. MUSCLE
TONE. The nurse determines the newborns muscle
tone by assessing the response to the extension
of the extremities. Good muscle tone is noted
when the extremities return to a position of fl
exion. REFLEX IRRITABILITY. The nurse assesses
refl ex irritability by observing the newborns
response to stimuli such as a gentle stroking
motion along the spine or fl icking the soles of
the feet. When this stimulation elicits a cry,
the score is 2. A grimace in response to
stimulation scores 1, and no response is a score
of 0. COLOR. The nurse assesses skin color for
pallor and cyanosis. Most newborns exhibit
cyanosis of the extremities at the 1-minute Apgar
check, and this normal fi nding is termed
acrocyanosis. A score of 2 indicates that
the infants skin is completely pink. Newborns
with darker pigmented skin are assessed for
pallor and acrocyanosis
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summary points ? Each patients labor and birth
experience is unique, and nurses play a vital
role in facilitating a positive outcome for the
patient, infant, and family. ? Nurses recognize
that the labor and birth experience is infl
uenced by a myriad of factors such as maternal
age and well-being, social support, and cultural
and religious beliefs and practices. ? Nurses
need a strong knowledge base about the
physiological processes of labor and birth in
order to provide safe and effective care. ? In
each of the four stages of labor, the nurse
uses well-developed assessment skills to
recognize the normal progression of labor, to
identify potential risks to the patient and
fetus, and to identify how and when to intervene
and consult with other health care providers. ?
The overall goal of intrapartal nursing care is
to promote comfort and safety of the patient, the
fetus, and the newborn infant. ? A positive
nursepatient relationship in which the woman
feels cared for and informed will empower her in
coping with her labor. ? Nurses include the
patient and her support person(s) in the planning
and delivery of care. ? The nursing care given
throughout labor and birth is an important
determinant of the womans overall perception of
her childbirth experience.
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THANKS A LOT