Mechanical theory of labor
Organ becomes filled and distended, empties itself.
Hormonal theory of labor
- Maternal progesterone and estrogen levels change.
- Maternal production of oxytocin and prostaglandin
- Increase in fetal cortisol
Signs of labor
- Braxton Hicks
- Cervical changes
- Bloody show
- Rupture of Membranes
- GI disturbance
- Sudden burst of energy.
Descent of fetus into the pelvis. Can occur two weeks before labor in primagravida (first pregnancy)
Braxton Hicks is
Irregular intermittent contractions that do not dilate cervix
Cervical changes during labor
Around 34 weeks the cervix begins to soften and become spongy. Effacement may begin
Bloody show during labor is
Cervical secretion,blood tinged mucus, and the mucus plug. Labor often begins 24-48 hours after bloody show
False labor is
- Irregular short contractions (1-2 hrs)
- Intervals between contractions stay the same
- stops when pt ambulates or changes positions
- Will stop with breathing, relaxing, comfort or hydration.
- Cervix May soften but doesn’t effect or dilate
- Contractions felt above navel.
True labor is
- Contractions at regular intervals and will gradually shorten
- Will increase in intensity and duration
- Will continue and often worsen with ambulation
- Usually isn’t stopped with breathing etc
- Cervix softens, effaces, and dilates.
- Felt in lower back and radiates to abd.
Responses to labor
- Increased CO and BP during contractions
- Increased RR and o2 consumption
- Bladder pushed forward and upward-encourage pt to void. Distention May impede fetal descent
- Peristalsis and absorption decrease- NPO
- Body temp increases and starts sweating
- WBC increases
- Small tears in vagina and perineum May occur from
- Relaxation of pelvic joints resulting in back age and leg cramps
- Endorphins increase pain tolerance and pressure at perineum produces physiologic anesthesia
Pain during labor is
- Expressed differently
- May be affected by culture
5 p’s of labor
- Psychological response
- Maternal passage is of primary concern when patient is planning a vaginal birth.
- True pelvis- must be big enough for baby
- Uterus- fundus thickens while lower uterus forms thinner tube.
- Cervix- contractions put pressure on fetus cause cervix pressure and dilation and effacing
- Vagina - has to stretch
- Perineum- pressure caused stretching and thinning
- Fetal size- head is largest part. Bones aren’t fused and can move and overlap through moms pelvis.
- Fetal attitude- relationship of fetal body parts. Ideal is flexion with head flexed on chest, arms over chest, and hips and knees over abdomen. Extension of limbs causes difficulty in labor.
- Lie- relationship of the cephalocaudal axis of fetus with cephalocaudal axis of mom
- Fetal presentation-determined by the fetal lie snd part of the fetus that enters the pelvis first. Most common is cephalic (head)
Head out first
Buttocks our first
Frank breed presentation
Hips flexed, knees extended
Head well flexed on chest, occiput is presenting part
Sinciput (forehead) is presenting part
Face is presenting part
- Engagement- fixation of the fetal presenting part in the maternal true pelvis in which the widest diameter of the presenting part is at or below the level of the ischial spines.
- *** immediate concern when a pts membranes rupture prior to engagement is a prolapsed cord***
- ***take fetal HR for full minute in that situation ****
Station - relationship of the fetal presenting part to the isnial spines, it is measured in cm above (-) or below (+) the isnial spines.
Fetal position- relationship of the identified landmark on the presenting part of the four quadrants of the mother’s pelvis.
- Primarily involuntary contractions of uterus with phases of relaxation.
- Rest restores oxygenation.
- Contractions have three phases.
- Secondarily voluntary use of abd muscles by mother to push.
Increasing intensity of contraction
Decreasing intensity of contractions
- Time from the beginning of one contraction to the next. Includes rest period.
- Persistent contractions at intervals shorter than 60 seconds will reduce oxygenation
The amount of time the uterus relaxes.
Is the length of one contraction of the increment to the conclusion of the decrement.
- Duration of a contraction SHOULD NOT BE LONGER THAN 90 SECONDS or interval LESS THAN 60 SECONDS.
- REDUCES FETAL 02
Strength of the contraction at acme
- Spontaneous, involuntary urge to bear down
- Triggered when presenting parts reach pelvic floor where receptors trigger release of oxytocin
- Anxiety reduces blood flow
- Responses influenced by culture
First sign of labor:
Dilation and effacement
- Starts with Regular contractions ends with cervical dilation
- Longest stage of labor
- Divided into three phases: latent, active, and transition
Latent phase of labor
- Ends with 3cm of dilation
- Longest phase
- Contractions 10-20 minutes lasting 15-30 seconds
- Contractions become more moderate
- Mom alert and talkative
- Educate on breathing
- Begins with 4 cm dilation
- Ends at 8 cm
- Contractions 3-5 minutes lasting 40-60 sec
- Have pt void q2h to prevent impeding fetal descent
- Intensity is stronger
- Focus on breathing.
- Begins at 8 cm
- Ends at 10 cm
- Contractions 2-3min lasting 60-90 sec
- Strong contractions
- Focus on breathing, relaxing( pant- blow breathing)
- No narcotics- reduce fetal oxygenation.
Characteristics during transition
- Focused on self
- Not following directions
- Very warm
- Increasing recital pressure
- Begins with complete cervical effacement and dilation of 10 cm
- End with birth of baby
- When cervix is 10 cm mom can push
- Pushing beforehand will cause cervical lacerations
Crowning- head seem at bulbs between contractions
Episiotomy- incision in perineum
Mechanism of labor
- Engagement- occurs when presenting part of the fetus is in the pelvis. At station 0
- Descent- begins with engagement and continued with each contraction
- Flexion- fetal head is bent forward and meets resistance during descent causing chin to rest in sternum. Allows narrowest part of head to enter the pelvic outlet.
- Internal rotation- takes place during second phase. Head rotated so the occipital is next to the symphysis pubis
- Extension- the occipital pivots under the symphysis pubis and the fetal head becomes extended and pushes upward out of the vagina. Head born during this.
- External rotation and restitution: head rotated back into normal alignment with shoulders
- Expulsion: rest of body is born with gentle downward pressure on baby’s head.
- Begins with birth of baby
- Ends with delivery of placenta
- Takes 5-30 minutes
- Most places dispose of placenta, occasionally clients ask for it back.
- MD will examine the placenta and membranes for intactness.
- Retained fragments can cause hemorrhage.
- First 4 hours after birth
- Assess for hemorrhage****
- Blood loss usually 250-500ml ***
- Uterus should remain contracted to control bleeding.
- *keep check in firmness and position of the fundus.
- *positioned in midline of abd level with umbilicus
- * regular voiding to prevent uterine hemorrhage.
- Mother may experience shaking and chills
- Bonding is important
- May us ice pack for 12 hours
Women having first child should enter facility when
Contractions are regular and every 5 minutes for an hour
Women having 2nd or later child should enter facility when
Contractions are 10 min apart for 1 hr
Determine fetal line and presentation.
A 15 beat fetal heart rate increase that lasts 15-20 seconds indicates
Good oxygenation to fetus
Mild fundus contractions.
Feels like tip of nose
Moderate fundus contractions
Feels like a chin
Strong fundus contraction
Feels like forehead
S/s of hyperventilating
Blurred vision, numbness, and tingling of hands and mouth.
Normal fetal heart rate
Disadvantage of epidural
Maternal Hypotension, bladder distention, epidural migration, n/v, pruritus, delayed resp depression.
Epidural contraindicated with
Low platelet count
Reverses narcotic- induced resp depression.
To prevent side effects of intrathecal block
Have client lie flat on back for hours.
Birth before 37 weeks
Terbutaline (breathine) (causes maternal tachycardia) and magnesium sulfate (causes warm flushing) given to inhibit contractions.
*keep calcium gluconate beside for magnesium sulfate side effects
Long, difficult or abnormal labor caused by any of the 5 ps
NPO 6 hours prior to prevent aspiration.
Hypertonic uterine contractions
Frequent uncoordinated contractions with increased resting time usually during latent phase of labor
Hypotonic uterine contractions
Also called uterine inertia, usually occurs during active stage. Contractions become weak and ineffective and may cease
Large baby size weighing more than 8.8 lbs.
When fetal head will not fit through mother’s pelvis
Secretion of catecholamines inhibit
When the active phase of first stage of labor lasts longer than 15 hours, the risk for fetal death increases.
- Too late for pain meds
- Labor lasting less than 3 hrs from onset of contractions to the birth.
- Complications: loss of coping ability, increased risk for uterine rupture, lacerations to cervical, vagina, and perineum.
- Fetal complications: hypoxia, distress, cerebral trauma
Precipitate labor tips
Breath with pt! No time to teach breathing. Walk them through it during contractions
- Birth occurs suddenly and unexpectedly with md to help.
- Stay with pt and call for help
Crowning May occur.
- Umbilical cord lies below the presenting part of fetus.
- May occur at any time and may not be visible
- Pressure on cord needs to be relieved
- Position mother on her back with her head lower than the rest of the body. Left modified sims with pillows under hips or knee chest position.
- Artificial rupture of membranes.
- Uses hook
- Assess fhr for a full minute
- Assess amniotic fluids for color, odor, consistency and quantity.
- Fluid should be clear with mild odor.
- Report watery green or discolored amniotic fluids
- Meconium stained fluids =fetal distress
Induction of labor
- Iv oxytocin at slow rate then increase slowly at regular intervals.
- Assess fhr and contractions, bp and pulse.
Augmentation- stimulations of uterine contractions after they start on their own
- Incision in abd and uterus
- Scheduled or unscheduled
- May be able to have vagina birth next time.
- Assess fundus post op. Firm and at umbilicus
Assisted birth: forceps
- Used on fetal head
- Cervix must be dilates, membranes ruptured, position and station of fetal head must be known.
- Assess infant for facial asymmetry
- Newborn may have bruising or edema
- Mom may have lacerations or hematoma
Assists birth: vaccum
- Risk: vaginal and recital lacerations
- Fetal risk: cephalobematoma, brachial plexus palsy, retinal and intracranial hemorrhage snd hyperbilirubinemia.
- Can cause an elevated dome over posterior fontanelle.
Care of infant
- Airway suctioned
- Apgar score assessed at 1 and 5 minutes after birth
- Apgar score of less than 6/10= fetal distress
- Warmth- skin to skin w/parent. Stockinette cap. Radiant warmer.
Care of mother
BP before and after oxytocic meds
Fundus= firm, grape fruit sized, around umbilicus
Clean and dry episiotomy
Mom and baby allow to bond.