LaborLabor

andand DELIVERYDELIVERY

LABORLABORLabor (parturition) is a series of events by which uterine contractions and abdominal pressure expel a fetus and placenta from a woman’s body.

Physiologic Effects of the Birth Physiologic Effects of the Birth ProcessProcess

MATERNAL RESPONSEMATERNAL RESPONSE

Cardiovascular System

Contraction increase blood flow to placenta increase blood volume increase BP slightly and slows pulse

pressure

Respiratory System

Labor pain Depth and rate respiratory alkalosis tingling of hands and feet, numbness, dizziness

Gastrointestinal System

Gastric motility N / V , thirsty, dry mouth

Urinary System

Sensation of urinary bladder due to intense contractions and regional anesthesia inhibits fetal descent

Placental ResponsePlacental ResponsePlacental Circulation During strong labor contractions the spiral arteries supplying the

intervillous spaces are compressed by the uterine muscles

maternal blood supply to the placenta and stops temporarily due to compression

Cardiovascular System

Alterations in the rate and rhythm of the fetal heart may result from normal labor effects or suggest fetal intolerance to the stress of labor

Pulmonary System

Catecholamines produced by the fetal adrenal glands in response to the stress of labor appear to contribute to the infant’s adaptation to extrauterine life.

- It stimulates cardiac contraction and breathing, quicken the clearance of remaining lung fluid and aid in thermoregulation

The Physiology of LaborThe Physiology of LaborPOSSIBLE CAUSES OF LABOR POSSIBLE CAUSES OF LABOR ONSETONSET

Progesterone Withdrawal Hypothesis

Prostaglandin HypothesisUterine stretch Oxytocin theory

Preliminary Signs of LaborPreliminary Signs of Labor

1. Lightening (“dropping”)

- or the descent of the fetal presenting part into the pelvic inlet, occurs approximately 10 to 14 days before labor begins

2. Increase in level of activity

(energy spurt or “ nesting”)

- r/t an increase in epinephrine release initiated by a decrease in progesterone produced by the placenta.

3. Slight loss of weight

- as progesterone falls, body fluid is easily excreted by the body increasing urine production leading to weight loss between 1 and 3 lbs.

4. Braxton Hicks Contractions

– painless, erratic uterine contractions that occur toward the end of pregnancy. They ready the cervix for labor, but cervical dilatation does occur with them.

5. Ripening of the cervix

- is an internal sign only on pelvic examination. Throughout pregnancy it is softer than normal like an earlobe. At term it will be butter-soft and it tips forward.

Signs of True LaborSigns of True Labor

1. Uterine contractions

- a rhythmic tightening of the uterus that aids in achieving cervical dilatation and effacement.

- Are the surest sign that labor has begun

2. Show or Bloody show

- as the cervix softens and ripens the mucus plug that filled the cervical canal during pregnancy is expelled.

3. Rupture of membranes

- experienced either as a sudden gush or scanty, slow seeping of clear fluid from the vagina.

- AF is continuously produced until delivery.

2 risk with ROM: Intrauterine infectionCord prolapse

Cord prolapse is the descent of the umbilical cord Cord prolapse is the descent of the umbilical cord into the vagina ahead of the fetal presenting part into the vagina ahead of the fetal presenting part with resulting compression of the cord between with resulting compression of the cord between the presenting part and the maternal pelvis.the presenting part and the maternal pelvis.

Factors Affecting Labor(5 Factors Affecting Labor(5 Ps)Ps)

1.Passenger - the size, presentation, and position of the fetus.

2. Passageway - shape and measurement of maternal pelvis.

3. Powers - forces of labor, acting in concert, to expel the

fetus and placenta.

4. Placenta - position of placenta

5. Psyche or Psychologic Response - A woman who is relaxed, aware, and

participating in the birth usually has a shorter, less intense labor.

PASSENGERPASSENGER

1. PASSENGER- is the fetus.

sinciput

vertex

occiput

Occipitofrontal-12 cmOccipitofrontal-12 cmSuboccipitobregmatic- 9.5 cmSuboccipitobregmatic- 9.5 cmOccipitomental- 13.5 cmOccipitomental- 13.5 cm

Biparietal diameter- 9.25Biparietal diameter- 9.25

Engagement- settling of the fetal head in the pelvis.

Molding - is a change in the shape of the

fetal skull produced by the force of

uterine contractions pressing the vertex of

the head against the not yet dilated cervix.

Variations in the Variations in the PassengerPassengerA. Fetal Lie – the orientation of the long

axis of the fetus to the long axis of the woman

Types:

1. Longitudinal2. Transverse3. Oblique

B. Attitude- degree of flexion a fetus assumes during labor or the relation of the fetal parts to each other.

Vertex- full flexion SOM- good attitude

Sinciput- moderate flexion OF- military attitude

Brow- partial extensionFace- poor flexion OM

- very poor attitude

C. Presentation – the fetal part that first enters the pelvis

Types:1.Cephalic2.Breech3.Shoulder

Types of PresentationTypes of Presentation

1. CEPHALIC = the fetal head presents itself to the passage, occurs in 97% of births

Classified as:

1. Vertex – most common; fetal head is completely flexed; smallest diameter of the fetal head (suboccipitobregmatic ) presents to the maternal pelvis

2. Military – fetal head is neither flexed nor extended; top of the head is the presenting part

3. Brow – fetal head is partially extended; sinciput is the presenting part

4. Face – fetal head completely extended; face is the presenting part

2. BREECH (buttocks) or (lower extremities)

a.Frank: thighs flexed, legs extended

on anterior surface,

buttocks presenting

b.Full or complete: thighs and legs flexed,

buttocks and feet

presenting(squatting)

c. Footling: one or both feet are presenting

3. SHOULDER (Acromion)

- It is also called as transverse lie and accounts for 0.2% of births

- A CS birth is necessary in a viable fetus

Position: relationship of reference point on fetal Position: relationship of reference point on fetal presenting part to maternal bony pelvis. Maternal presenting part to maternal bony pelvis. Maternal bony pelvis divided into 4 quadrants (R and L anterior, bony pelvis divided into 4 quadrants (R and L anterior, R and L posterior)R and L posterior)

Station- refers to the relationship of the presenting part of a fetus to the level of the ischial spine.

2. PASSAGE2. PASSAGE Refers to the route the fetus must travel from

the uterus through the cervix and vagina to the external perineum.

Gynecoid Gynecoid Inlet rounded with all inlet

diameters adequate.

Midpelvis diameters adequate with parallel side walls.

Outlet adequate

Favorable for vaginal birth

AndroidAndroidInlet heart-shaped Midpelvis diameters reduced Descent into pelvis is slow Not favorable for vaginal

birth

Anthropoid Anthropoid Inlet oval in shapeOutlet adequate

Platypelloid Platypelloid Inlet oval in shapeOutlet capacity inadequateNot favorable for vaginal birth

3. POWER3. POWER

Major forces: Involuntary and voluntary

Involuntary: includes frequency, regularity, intensity and duration.

Voluntary: bearing-down efforts. The contraction of levator ani muscles.

Uterine contractionUterine contraction

3 phases of labor 3 phases of labor contractioncontraction1. INCREMENT – building up of

the contraction (longest phase)

2. ACME – peak of the contraction

3. DECREMENT – letting up of the contraction

Terms to describe uterine Terms to describe uterine contractions during laborcontractions during laborDURATION - measured from the

beginning of a contraction to the completion of the same contraction

FREQUENCY- refers to the time between the beginning of one contraction and the beginning of the next contraction

INTERVAL- refers to the time between the end of one contraction to the beginning of the next contraction

INTENSITY – refers to the strength of the contraction during acme.

4. POSITION4. POSITION

Maternal positioning during labor Influence pelvic size and contoursAffects pelvic joints, facilitate descent

and rotationE.g. squatting – enlarges the pelvic

outlet by approximately 25%Kneeling removes pressure on the

maternal vena cava and assists to rotate the fetus in the posterior position (Breslin and Lucas, 2003)

1. Semi-recumbent position- woman sits with upper body elevated.

2. Lateral position- Removes pressure from the vena cava

compression and back to enhance uteroplacental perfusion and relieves backache.

3. Upright position- Effect of gravity enhances the

contraction cycle and fetal descent.

Squatting Squatting

4. Hands and knees position- All fours.- Facilitates internal rotation of the

fetus.

5. PSYCHE5. PSYCHE A woman’s psychological outlook refers to the psychological state or feelings that a woman brings into labor.The woman manage best in labor typically are those who have a strong sense of self esteem and a meaningful support person with them.Women without inadequate support can have an experience so frightening and stressful they can develop PTSD.

true labor VERSUS false labortrue labor VERSUS false laborTRUE LABORTRUE LABOR FALSE LABORFALSE LABOR

ContractionContraction Regular, increasing frequency Regular, increasing frequency and intensity, shortening of and intensity, shortening of intervalinterval

Irregular, no change in Irregular, no change in frequency, duration and frequency, duration and intensityintensity

DiscomfortDiscomfort Felt from the lower back Felt from the lower back radiates to the abdomen in radiates to the abdomen in wavewave

Pain remains in the Pain remains in the abdomen and groinabdomen and groin

Rest/Rest/

ActivityActivity

Continue no matter what the Continue no matter what the woman’s level of activity woman’s level of activity

Often disappear with Often disappear with ambulation and sleep ambulation and sleep

CervixCervix Achieve dilatation of cervixAchieve dilatation of cervix Does not achieve cervical Does not achieve cervical dilatationdilatation

Four Stages of Labor:

1. First Stage: Dilationa. Latent or preparatory phaseb. Active phasec. Transition phase

2. Second Stage: Crowning3. Third Stage: Birth of the

baby and delivery of the placenta

4. Fourth Stage: Recovery

FIRST STAGEFIRST STAGE- begins with the initiation of true labor - begins with the initiation of true labor contractions and ends when cervix is fully dilated.contractions and ends when cervix is fully dilated.

The latent or preparatory phase onset of regularly perceived uterine

contractions rapid cervical dilatation begins.

Contractions mild and shortlasting 20 to 40 seconds.

Emotional status: excited, anxious, talkative, and ambivalent about the ability to cope with labor; “in control”

Active PhaseRapid cervical dilatation : 4 cm to 7 cm Contractions

Stronger lasting 40 to 60 seconds every 3 to 5 minutes.

lasts approximately 3 hours in a nullipara 2 hours in a multipara

Show : increased vaginal secretionsPerhaps spontaneous rupture of the membranes may occur. Emotional status:Intoverted, lessresponsive, decreased attention span, intenseconcentration on“work of labor”, someloss of control may occur along with a growing irritability

Transition Phase Contractions peak in intensity occurring every 2-

3mins with a duration of 60-90secs Membranes will rupture as a rule at full

dilatation (10 cm) Show will be present as the last of the mucus

plug from the cervix is released. By the end of this phase, full dilatation (10 cm)

and complete cervical effacement (obliteration of the cervix) have occurred.

Emotional status: decreased confidence, loss of control, desire to give up and go home, fear of death of self and fetus; does not want to be touched and rejects help.

Comfort Measures for the Laboring Comfort Measures for the Laboring WomanWoman

Do not leave alone in active labor.Do not leave alone in active labor. Change soiled and damp linen promptly.Change soiled and damp linen promptly. Provide mouth care.Provide mouth care. Ice chips, lubricate lips.Ice chips, lubricate lips. Keep room cool, uncluttered, quiet and Keep room cool, uncluttered, quiet and

privacy.privacy. Promote participation of coach.Promote participation of coach.

SECOND STAGESECOND STAGE- extending from the time of full dilatation until - extending from the time of full dilatation until the infant is bornthe infant is born

“Crowning”As she pushes, using her

abdominal muscles and the involuntary uterine contractions, the fetus is pushed out of the birth canal.

Mechanism of a spontaneous Mechanism of a spontaneous vaginal delivery/ Cardinal vaginal delivery/ Cardinal movementsmovements

• Definition: A mechanism of labor is Definition: A mechanism of labor is a series of passive, adaptive a series of passive, adaptive movements of the fetal head and movements of the fetal head and shoulders through the birth canal. shoulders through the birth canal.

Mechanisms of LaborDescentFlexionInternal RotationExtensionExternal RotationExpulsion

1. Descent- downward movement of the BPD of the fetal head to within the pelvic inlet.

2. Flexion- the head flexes forward onto the chest, making the smallest anteroposterior diameter SOM present to the birth canal.

3. Internal rotation- fetal head turns to allow the BPD to pass between the ischial spine

4. Extension- fetal head extends upward when it reaches the perineum; occiput pivots beneath the pubic symphysis.

5. External rotation- fetal head turns, realigning with shoulders, on emerging from the pelvis; shoulders move through pelvis and are delivered from under the symphysis pubis and the from over the perineum.

6. Expulsion- delivery of the fetal trunk follows the birth of its head and shoulders.

THIRD STAGE (Placental stage)THIRD STAGE (Placental stage)From delivery of the baby to delivery of the placenta. This From delivery of the baby to delivery of the placenta. This stage usually lasts only a few minutes but may last up to stage usually lasts only a few minutes but may last up to 30 minutes30 minutes..

Placental Separation◦ Folding and separation of the placenta occur.

◦ Active bleeding maternal surface of the placenta the bleeding helps to separate the placenta still further by pushing it away from its attachment site.

Signs of placental separation◦Lengthening of the umbilical cord

◦ Sudden gush of vaginal blood ◦ Change in the shape of the uterus

◦Firm contraction of the uterus◦Appearance of the placenta at the vaginal opening

Made up of 15-20 lobes called cotyledons 2 mechanisms of placental separation 1. SCHULTZE – separates from the inside to the outer

margin; expelled with the fetal side ; “Shiny” 2. DUNCAN- separates from the outer margins inward,

rolls up and presents sideways with the maternal surface; “Dirty”

Fourth stageFourth stage Recovery: The woman is observed

frequently for signs of hemorrhage or other complications; 1-4 hours after birth

Hemodynamic changes occur Blood loss ranges from 300-500ml Uterus remains contracted in the midline

Possible complications for Possible complications for the mother include:the mother include:rupture (tearing) of the uterus hemorrhage (heavy bleeding)

after the delivery bruising or tearing of the cervix

or vagina tearing of the rectum bruising or irritation of the

bladder.

Maternal Adaptation during Maternal Adaptation during the Postpartum Periodthe Postpartum Period Normal uterine involution occurs at a

predictable rate. One hour after chilbirth, the fundus is at the level of the umbilicus.

On the 1st postpartum day, the fundus is approximately 1 fingerbreadth or 1 cm below the level of the umbilicus.

Thereafter, it descends downward at the rate of 1 cm per day until it becomes a pelvic organ again on the 10th day postpartum.

Lochia rubra, serosa and alba.

Normal blood loss during NSVD 300 to 500 ml.

CS: 500 to 1,000 mL.

Maternal Role DevelopmentMaternal Role Development Taking In Phase Mother is dependent, has difficult making

decisions and needs assistance with self-care. Can last several hours to days.

Taking Hold PhaseAfter she has rested and recovered from stress

of delivery, the new mother has energy for the infant. Lasts 2 days to several weeks.

Letting Go PhaseFamily relationships are adjusted to

accommodate the infant. Give up the fantasy child and gets to know the real child.

“Postpartum blues” = a temporary depression that usually begins on the 3rd day and lasts for 2-3 days.

S/S: tearful, difficulty sleeping and eating, and feel generally down.

Psychological adjustment, plus fatigue, disturbed sleep patterns, and discomfort may contribute.

Focus of early postpartum period:1. Preventing and detecting hemorrhage2. Treating pain3. Preventing infection4. Detecting and treating urinary retention5. Promoting sleep6. Promoting healthy parental-newborn attachment.

POSTPARTUM COMPLICATIONS

1. HEMORRHAGE - 1-4 hrs postpartum is the most critical stage

Causes:

a. Laceration

b. Placental retention

c. Uterine rupture

d. Uterine inversion

e. Uterine atony

2. INFECTIONS a. Endometritis – Endometriosis is the growth

of endometrial tissue outside the uterus. When infected, it is called endometritis.

Clinical manifestations: foul smelling vaginal discharge fever & chills profuse bleeding b. Episiotomy Infection

Operative Obstetrical Procedures

Forceps DeliveryForceps Delivery

Forceps Delivery – method of delivering infants through the use of forceps extraction

- 2 double-crossed, spoonlike articulated blades that are used to assist in delivery of fetal head

- may cause damage on the facial nerve of the baby

Vacuum DeliveryVacuum Delivery – method of delivering an infant using a vacuum applied over the scalp of the baby

- may cause caput succedaneum

Cesarean SectionCesarean SectionIn the case of severe obstetric emergencies, the time In the case of severe obstetric emergencies, the time from decision to delivery is ideally within 30 minutes from decision to delivery is ideally within 30 minutes ..

3 types

a. Low Segment CS – method os choice since lower segment is thinner, fewer bld vessels, passive during labor

b. Classical CS – indicated for transverse lie, placenta previa, adhesion of tissues

c. Pfannenstiel or bikini