3. The Five “Ps” of
Labor
Passageway:
Pelvis -maternal bony and tissues
Passenger: the fetus
Powers: primary and secondary forces of labor
Position: maternal position y
Psyche: psychological component of mother
5. Passageway:
Pelvis
Pelvis: Fusion of ilium, ischium,
pubis & sacral bones
– False pelvis: above pelvic
inlet
– True pelvis: inlet, mid-pelvis
and outlet
4 main pelvic types:
Gynecoid: round, most
common type, vaginal birth
(female type)
Android: heart-shaped,
usually have C/S(male type)
Anthropoid: oval, vaginal
birth (often forceps)(Ape like)
Platypelloid: flat, least
common, vaginal birth.
6. Fetal Skull
Anatomy
Bones: frontal, occipital, 2
parietal, and 2 temporal
Molding: overlapping of fetal
skull bones during labor;
resolved by 3 days after birth
Sutures: membranous tissue
between bones of skull
Fontanels: membrane-filled
spaces where sutures intersect: ·
Anterior: large; diamond
shaped (junction of 4 sutures);
closes by 18 months after birth ·
Posterior: small; triangular
(junction of 3 sutures); closes 6 to
8 weeks after birth
7. Passenger-Fetal Attitude and Fetal Lie
Attitude: relation of fetal parts to one another −
Flexion: normal −
Hyperextension: abnormal
Lie: relationship of fetal longitudinal axis to maternal longitudinal axis
Longitudinal: fetal spine parallel to mother’s spine
Transverse: fetal spine at right angle to mother’s spine
8. Passenger-Fetal
Presentation
The Fetal part entering pelvis first (felt on
vaginal exam) –
Cephalic: occiput presents in vertex (brow,
face or military are other cephalic
presentations)
Breech: sacrum presents, complete, frank or
footling breech
Shoulder: scapula presents
9. Passenger: Fetal
Position
relation of fetal presenting part
to maternal pelvis
First letter: side of maternal
pelvis that presenting part is
toward (R: right or L: left)
Second letter: landmark of
fetal presenting part: O for
occiput, S for sacrum, M for
mentum (chin), or Sc for scapula
(shoulder)
Third letter: location of
presenting part in relation to A
for anterior, P for posterior or T
for transverse portion of the
maternal pelvis y Most
common: ROA or LOA
10. Passenger: Fetal
station
Relationship of presenting part to ischial spines of
maternal pelvis.
The level of the Ischial spines mark the narrowest
diameter through which fetus must pass
Station at level of spines is 0
If higher than ischial spines, it is negative number. -
1,-2
If below the ischial spines, it is a positive number-
+1,+2
11. Passenger:
Engagement –
Fetal head
Engagement is when largest diameter of
presenting part (BPD) crosses the pelvic inlet and
can be detected by vaginal exam
Floating: presenting part directed towards pelvis,
but can easily be moved out of the inlet. Both
fetal poles- occiput and sinciput felt easily.
Ballotable: presenting part dips into inlet, yet is
displaced with upward pressure from
obstetricians fingers
Engaged: presenting part fixed in pelvic inlet;
cannot be dislodged
12. Power:
Forces of Labor Primary &
secondary powers combine
to expel fetus and placenta
from uterus
Primary (involuntary)
forces: contractions of
uterine muscle fibers
Secondary (voluntary)
forces: use of abdominal
muscles during second
stage of labor to facilitate
descent & delivery of fetus
13. Primary Forces of Labor
Effacement: Shortening and thinning of cervix
during first stage of labor. Measured from 0% to
100%.
Dilation: Opening or widening of cervix as labor
progresses.
Measured from 0 to 10 cm.
Is complete when cervix not palpable on vaginal
examination
14. Position of Laboring Woman
Affects circulation, fatigue & comfort
1. Upright position (walking, sitting. Standing, squatting) beneficial –
Promotes descent of fetus
Improves blood flow
Relieves backache
Straightens axis of birth canal
Increases pelvic outlet
2. Hands & knees(All fours) may relieve back pain, help fetus to rotate
3. Lateral position may help fetus rotate favorably and slow birth
4. Supine position- worst as it compromises blood flow to uterus and fetus –
should be avoided as far as possible.
15. Psyche
Preparation for childbirth – reading, antenatal exercise
Sociocultural heritage
Previous childbirth experience
Support from significant others- family, husband, friend, student,
staff.
Emotional status – fearful, anxious, confident, relaxed mentally
prepared.
Environmental influence
Role of health personal and treating team, family , friends, and
reading materials.
16. Cardinal Movements of
Labor
1. Engagement - presenting part fixed into pelvic
inlet
2. Descent –of fetal head into pelvis
3. Flexion – of fetal head on neck as it reaches
levator ani muscle.
4. Internal rotation -by 180degrees of fetal head to
accommodate widest diameter of maternal pelvis
5. Extension - of fetal head as it comes under pubic
symphysis
6. Restitution - as head turns 45° to untwist neck
7. External rotation -viewed as head turns 45° to
align shoulders with widest diameter of pelvis
8. Expulsion- as anterior shoulder slips under pubis
17. Signs &
Symptoms of
Labor
Preceding labor: – Lightening – Bloody show – Stronger
Braxton Hicks – Cervical ripening – Diarrhea – Energy
burst
Onset of labor: – Regular contractions with progressive
frequency and intensity –
Progressive effacement and dilation of cervix –
Progressive descent of presenting part
Marked on the Partogram
18. Stages of labor
First stage- onset of labor till full
cervical dilatation
Second stage- delivery of baby
Third stage – placenta delivery
19. Stages of Labor
First stage: 6-8 hours
multi, 8-10 hours primi.
Begins with onset of true
labor and ends with
complete dilation -
Second stage: 30 minutes
multi, 30 minutes-1 hour
primi
Begins with complete
dilation and ends with
birth of infant
Third stage: 15 minutes
multi, 30 minutes primi
Begins with expulsion of
infant and ends with
expulsion of placenta
Fourth stage:
Begins with expulsion of
placenta, lasting 4 hours -
to monitor vital signs,
vaginal bleeding and urine
passage by the mother.
20. First Stage of
Labor
Latent Phase
Cervical dilation: 0 - 3 cm
Maternal pain usually under
control
Active Phase
Cervical dilation: 4 - 7 cm
Contractions closer, longer &
stronger.
Mom working to maintain
control
Transition
Cervical dilation: 8 - 10 cm
Increased bloody show; urge
to push Mom may be irritable,
discouraged and tired or
dehydrated
21. Second Stage of Labor
10 cm to birth of baby
0 - 30 min in multipara; up to 2 hours in nullipara
Bearing down pains- urge to pass stool.
Urge to push increases , as presenting part descends,
with
increased rectal & perineal pressure.
sensation of burning & stretching of vagina & perineum
Mom may be eager or reluctant to push ’
Crowning of fetal head:
bulging and thinning of perineum and opening of vagina
as widest part of head (biparietal diameter) presses
downward onto the perineum and becomes visible prior
to delivery.
22. Birthing and after
Check baby
Time of birth
Cry
Apgar score at 1 and 5 minutes
Sex
Weight
Anomaly- structural
Head and abd circumference
Ponderal index
Skin color
Reflexes
Passage of urine
23. Third Stage of
Labor
From birth of infant to birth of
placenta
Usually ≤ 30 minutes •
Uterine surface volume
decreases, shearing placenta
from wall
Signs of placental separation :
Separation causes gush of
blood vaginally ,
Umbilical cord appears to
lengthen.
Mild uterine contractions;
feeling of fullness in vagina as
placenta is expelled
Supra-pubic bulge
26. Episiotomy-
Perineal
incisions
Surgical incision into perineum to enlarge vaginal opening during
2nd stage
Midline:
incision made from vagina toward rectum.
Advantage: muscle fibers split lengthwise with faster/less painful
healing. Disadvantage: 30 % extend into 3rd/4th degree
Medio-lateral:
incision from vagina obliquely toward one buttock.
Advantage: larger episiotomy possible; rectal structures avoided.
Disadvantage: cut across muscle fibers causes more pain during
healing.
27. Lacerations
Lacerations to perineum or surrounding tissue may occur during childbirth; 3rd and
4th degree lacerations most commonly occur after midline episiotomy performed
1st degree :
involves only epidermal layers; if no bleeding may not need repair
2nd degree:
epidermal and muscle/fascia involvement requires suturing
3rd degree:
extends into rectal sphincter
4th degree:
through rectal mucosa
28. Non-
pharmacologic
Pain
Management
Position change to decrease weight of fetus
Hydrotherapy: warm tub or shower, hot towels
Breathing techniques to prevent breath-holding, facilitate
O2/CO2 exchange
Hypnotherapy
Relaxation techniques: imagery, verbal instruction,
massage, soft music, therapeutic touch
Childbirth prep: Dick-Read, Bradley, Lamaze
ANTENATAL EXERCISE CLASSES FOR COUPLES
29. Pharmacologic Pain
Management
IV narcotics For example: Fentanyl, Pethidine and phenargan. (Need to have Nalorphin -)
Advantages: Rapid onset, short duration.
Disadvantages: Can decrease UC frequency & intensity & cause neonatal respiratory depression
Local infiltration: Anesthetic injected into perineum to numb tissues before episiotomy incision or
suturing – 10 ml of 1% lignocaine (Xylocaine)
Advantages: Rapid onset
Disadvantages: vascular tissue quickly disperses medication & repeated injections may be needed
Epidural anesthesia
Advantage- Very effective, Top up doses possible, operative delivery easy if needed.
Disadvantage- Can prevent or slow down the bearing down sensation and thus urge to push in
second stage- needing assistance by forceps or ventouse.
Nitrous oxide inhalation- laughing gas.
30. Some aspects of patient education, for timely reaching delivery
unit.
31. Summary of approach to labor patient
Greet and give your name to patient, ask her name, age and also permission to examine verbally
Greet and give
Take history and clinically determine if in true or false labor from history
Take
Do general, complete physical examination, abdominal and vaginal examination to determine stage of labor clinically.
Do
Start the white apron, gowning, gloving, use of googles , opening the delivery pack and checking delivery and episiotomy
instruments.
Start
Keep talking to laboring patient explaining what you plan to do next and to avoid pushing if she has crowned with fetal head
visible at the introitus.
Keep
32. Summary
Conduct delivery of baby completely till cord
clamping,
assessing condition of baby and placing on
mother’s belly if all good.
Inj. Oxytocin at delivery of anterior shoulder/
after delivery of placenta
Conduction of delivery of placenta by
controlled cord traction, after explain signs of
placental separation – examining of placenta
and membranes.
Examining uterus and vagina – for bleeding,
clots, and contractility of the uterus.
Check perineum for tears, suture episiotomy if
given.
Complete by doing a Per- vaginal and per
rectal examination before transferring patient
to the post deliver area.
Help mother pass urine ,check vitals, bleeding,
fever in the fourth stage.
Encourage breastfeeding,
Discuss briefly contraception before
transferring patient to post natal ward.
33. Suggested
reading and
homework
Ten teachers
Williams Obstetrics
Look up
Maternal pelvis and fetal head-diameters
Partogram
Care in I st, 2nd 3rd and 4th stages of labor.
Episiotomy types and repairs and complications