Stages of Labor Flashcards
When does the onset of labor usually occur?
38 - 42 weeks
What are the 4 P’s of labor?
- Power
- Passenger
- Pelvis
- Psyche
What are the aspects of “power”? (2)
- Uterine contractions
- Cervical effacement / dilation
What are contractions?
Rhythmic tightening / pulling of uterine muscles (increment, acme, decrement)
______ DO NOT dilate / efface the cervix
Braxton Hicks contractions
What is contraction duration?
Start to end of same contraction
What is contraction frequency?
Start of one contraction to start of next contraction
What is the increment of a contraction?
Contraction increases / muscle tightens
What is the acme of a contraction?
Peak / strongest point of a contraction
What is the decrement of a contraction?
Contraction decreases / muscle relaxes
How is contraction intensity measured?
By pressing the fingertips into the fundus
Describe the comparisons used to measure contraction intensity (3)
- Mild = fundus indentation similar to nose
- Moderate = fundus indentation similar to chin
- Strong = fundus indentation similar to forehead
What is cervical effacement?
Thinning / shortening of the cervical canal (usually 2 - 3 cm –> becomes paper thin)
Describe the process of cervical effacement (2)
- As the cervix begins to efface, more amniotic fluid collects below the fetal head
- Increased amount of amniotic fluid creates hydrostatic pressure on the cervix
Describe cervical dilation
Enlargement of the cervical opening for passage of the fetus
Describe the occurrence of cervical effacement / dilation in primigravida mothers
Effacement typically occurs before dilation
How often should the cervix be checked for dilation?
Once every hour
What are the signs of impending labor? (6)
- Lightening
- Cervical ripening
- Bloody show
- Backache
- Nesting
- ROM
What is lightening?
Fetus settles into pelvic inlet
When does lightening occur?
2 weeks before labor in primigravida
What are the manifestations of lightening? (3)
- Easier breathing
- Decreased pressure on the diaphragm
- Increased bladder pressure - frequent urination
What is bloody show?
Blood-tinged secretion of mucus plug from cervix
When does bloody show occur?
24 - 48 hours before labor
When can blood-tinged mucus occur and be confused with bloody show?
During a vaginal exam
When does nesting / sudden burst of energy occur?
24 - 48 hours before labor
Why should induction occur if labor hasn’t started 24 hours after ROM?
To prevent infection
How can ROM be distinguished from urinary incontinence?
Nitrazine paper - will turn blue if amniotic fluid
Describe contractions associated with true labor (2)
- Regular contractions
- Increase in duration / frequency
Describe discomfort / pain associated with true labor (3)
- Back / lower abdomen
- Worse with activity / walking
- Not relieved with mild sedation
Describe cervical changes associated with true labor (2)
- Progressive effacement / dilation
- Bloody show
Describe contractions associated with false labor (2)
- Irregular contractions
- No increase in duration / frequency
Describe discomfort / pain associated with false labor (3)
- Groin / middle abdomen
- Improved with activity / walking
- Relieved with mild sedation
Describe cervical changes associated with false labor (2)
- No effacement / dilation
- No bloody show
Why is it important to NEVER lay supine when pregnant (regardless of labor stage)?
Risk of vena cava syndrome
Which position is best to prevent vena cava syndrome?
Left lateral position
Describe vena cava syndrome
Uterus puts pressure on vena cava - cuts off blood return
What are the manifestations of vena cava syndrome? (4)
- Pallor
- Clammy skin
- Hypotension
- Late decelerations
What are the labor triggers? (2)
- Prostaglandin
- Oxytocin
What is the drug class of cervidil?
Prostaglandin E2 (PGE2)
What is the drug class of misoprostol (Cytotec)?
Prostaglandin E1 (PGE1)
Which class of prostaglandin causes faster and more effective cervical ripening?
Prostaglandin E1 (PGE1)
What is the drug class of indomethacin?
Prostaglandin inhibitor
What is the purpose of indomethacin?
Inhibits premature labor
When can indomethacin be used?
≤ 32 weeks
What is the drug class of pitocin?
Oxytocin
IV pitocin can be used to induce labor if the cervix is ______
Inducible (softened)
What hormone is needed to sustain a pregnancy?
Progesterone
Describe the length of labor in multipara mothers compared to primipara mothers
Multipara labors are typically faster - the more times that the cervix has been stretched, the faster it will dilate
If a patient has had several previous births and been in labor for hours prior to admission, the nurse should …
Do a vaginal exam ASAP after admission to check for dilation
When is the first stage of labor?
Cervical effacement / dilation from 1 - 10 cm
The first stage of labor consists of what 3 sub-phases?
- Latent phase
- Active phase
- Transition phase
How effaced / dilated is the patient during the latent phase?
- 0% - 40% effaced
- 0 - 3 cm dilated
How effaced / dilated is the patient during the active phase?
- 40% - 80% effaced
- 4 - 7 cm dilated
How effaced / dilated is the patient during the transition phase?
- 80% - 100% effaced
- 8 - 10 cm dilated
What is the frequency / duration of contractions during the latent phase?
Q 5 - 30 minutes, lasting 30 - 45 seconds
What is the frequency / duration of contractions during the active phase?
Q 2 - 5 minutes, lasting 45 - 70 seconds
What is the frequency / duration of contractions during the transition phase?
Q 2 - 3 minutes, lasting 45 - 90 seconds
Describe maternal behaviors during the latent phase (3)
- Anticipation / excitement
- Teachable / follows directions
- Pain is controlled
Describe maternal behaviors during the active phase (2)
- Concentration / serious
- Fear of being alone
What nursing interventions should take place during the active phase of labor? (4)
- Position
- Urination
- Relaxation
- Respiration
Pain medication should be avoided until ______
4 cm - can slow down labor
Why is it important to urinate frequently during the active phase of labor?
A full bladder can increase the intensity of contractions
Describe maternal behaviors during the transition phase (4)
- Screaming / crying
- Shaking / chills
- Nausea / vomiting
- Need for BM - rectal pressure
What are the aspects of “passenger”? (4)
- Fetal attitude
- Fetal lie
- Fetal presentation
- Fetal position
Define fetal attitude
The relationship of fetal parts to each other
Describe proper fetal attitude at term (5)
- Head flexed (vertex)
- Chin tucked
- Arms crossed over chest
- Thighs against abdomen
- Knees flexed
Define fetal lie
The relationship of fetal and mother spines
What are the 2 types of fetal lie?
- Longitudinal
- Transverse
Describe longitudinal fetal lie
Fetal and mother spines are parallel (preferred)
Describe transverse fetal lie
Fetal and mother spines are perpendicular (cannot deliver vaginally)
Define fetal presentation
The manner in which the fetus enters the pelvis
What are the 3 types of fetal presentation?
- Cephalic
- Breech
- Transverse
What is the presenting part in cephalic presentation?
Occiput
Which type of cephalic presentation is shown?
Vertex
Which type of cephalic presentation is shown?
Face
Which type of cephalic presentation is shown?
Brow
When does the anterior fontanel close?
18 months
When does the posterior fontanel close?
8 - 12 weeks
Which fontanel is larger / easier to palpate?
Anterior fontanel (2 - 3 cm)
What is the presenting part in breech presentation?
Sacrum
What are the complications associated with breech presentation? (2)
- Cord prolapse
- Passage of meconium
Describe frank breech presentation
Flexed hips
Describe complete breech presentation
Flexed hips and knees
Describe incomplete / footling breech presentation
One or both feet extending at the hips and knees
What is the presenting part in transverse presentation?
Acromion
Define fetal position
Relationship of fetal landmarks to the pelvis
Which fetal position has the best outcome?
Occiput anterior
Which fetal position is shown?
Right occiput anterior (ROA)
Which fetal position is shown?
Left occiput anterior (LOA)
Which fetal position is shown?
Right occiput posterior (ROP)
Which fetal position is shown?
Left occiput posterior (LOP)
Why is occiput posterior position not preferred?
Increased pressure on sacral nerves - causes back pain
______ is used to determine the presentation / position of the fetus
Leopold’s maneuver
Describe the Leopold Maneuver
1st - determines fetal direction (longitudinal or transverse)
Describe the Leopold Maneuver
2nd - determines position of fetal back and small parts
Describe the Leopold Maneuver
3rd - determines degree of engagement
Describe the Leopold Maneuver
4th - determines fetal occipital prominence
It is important to determine the ______ of the pelvis in early pregnancy
Diameter
What are the 4 types of pelvis shape?
- Gynecoid
- Anthropoid
- Android
- Platypelloid
Describe gynecoid pelvis shape (2)
- Round / wide shape
- Most favorable for vaginal delivery
Describe anthropoid pelvis shape (2)
- Oval / narrow shape
- Adequate for vaginal delivery
Describe android pelvis shape (2)
- Heart shape
- Not favorable for vaginal delivery
Describe platypelloid pelvis shape (2)
- Flat shape
- Not favorable for vaginal delivery
What are the aspects of “psyche”? (3)
- Level of excitement, tension, and fear
- Unfamiliar environment
- Loss of control / pain
When is the second stage of labor?
From 10 cm until the baby is born
What are the 7 cardinal movements of labor?
- Engagement
- Descent
- Flexion
- Internal rotation
- Extension
- External rotation / restitution
- Expulsion
When is the fetus considered engaged?
When the biparietal diameter (BPD) passes through the pelvic inlet
What is the biparietal diameter (BPD)?
The largest transverse diameter of the fetal head
______ is the most important indicator of fetal size
Biparietal diameter (BPD)
Define floating / ballottable
Fetal head freely moveable above the pelvic inlet
Describe descent
Progressive movement of fetus through the pelvis
How is descent measured?
Station
Where is 0 station?
The ischial spine
What does negative station indicate?
Number of cm above the ischial spine
What does positive station indicate?
Number of cm below the ischial spine
At what station is the fetal head visible (crowning)?
+3
Describe flexion
Chin becomes tucked
Describe internal rotation
Fetal head turns to fit through pelvis (ideally assumes occiput anterior position)
Describe extension
Fetal head is born (back of the head exits first)
Describe external rotation / restitution
Realignment of head and shoulders (turn 45 degrees)
Describe expulsion
Anterior shoulder is delivered, followed by posterior shoulder and rest of the body
When is the third stage of labor?
Expulsion of the placenta
Describe placental separation (2)
- Sudden gush of blood
- 8 inches of umbilical cord exits vagina
Placenta separation indicates that …
The placenta is ready for expulsion
How long does placental expulsion typically take?
5 - 20 minutes
______ control bleeding during placental expulsion
Uterine contractions
______ is routinely given after placental expulsion
IV pitocin
What intervention should take place after an unattended delivery if no medication can be ordered?
Put the baby to the breast - breastfeeding stimulates oxytocin
A placenta is considered retained after ______
30 minutes
When is the fourth stage of labor?
1 - 4 hours postpartum recovery
What is the average amount of blood loss during birth?
250 - 500 cc
What changes occur during the first 1 - 4 hours postpartum? (2)
- Physiologic readjustment
- Hemodynamic changes
What is the primary focus during the first 1 - 4 hours postpartum?
Uterine contractility
How often should vital signs be assessed during the first 1 - 4 hours postpartum?
Q 15 minutes
Describe the nursing interventions associated with uterine contractility postpartum (2)
- Palpate for firmness Q 15 minutes
- If boggy, massage to prevent uterine atony / hemorrhage
