1. Physiological Adaptations
Normal
Labor and Delivery
Physiological Adaptations
Chapter 17
Presented by
Ann Hearn

2. LABOR The process by which the products of conception are expelled
from the body

3. UTERINE CONTRACTIONS
Contraction - exhibits a wavelike pattern that begins slowly climbing (increment) to a peak (acme), and decreases (decrement)
Intensity - strength of uterine contraction
acme
Define the characteristics of uterine contractions. P. 318
Decrement
Increment

4. Uterine Contractions
2. Define the following terms related to uterine contractions:
a. frequency
b. duration
c. intensity
d. interval
Duration- from beginning of one contraction to the end of the same contraction
Frequency- from beginning of one contraction to the beginning of another contraction
Interval - resting time between contractions allows for placental perfusion

5. Uterine Contraction - review

6. Assessment of Contraction
1. Subjective symptoms by woman
2. Palpation and timing by the nurse
3. Use of Electronic Fetal Monitor
(EFM)

7. Opposing Features of Uterine Activity
Upper 2/3 of uterus contracts actively
Lower third and cervix are passive
1. b. uterine activity is characterized by opposing features, explain.
These lead to downward progression of fetus
with each contraction

8. Uterine Muscle

9. CERVICAL ASSESSMENT Dilation:
the size of the cervical opening (measured in centimeters).
Full dilation = 10cm
Effacement:–estimated amount the cervix has thinned (measured in percent)
Complete effacement = 100%
3. Define the following terms related to cervical changes during labor: p. 319
a. effacement
b. dilation

10. Myometrial Activity Effacement- thinning of the cervix (%)
Dilation – enlargement and widening of the os (cm)
4. How are cervical dilation and effacement measured? P. 320

11. Cardiovascular System Changes
During each contraction, blood flow to the placenta gradually decreases, resulting in an increase in the woman’s blood volume causing her B/P to increase and slowing of her pulse.
Because these changes occur during a contraction, it is best to assess vital signs between contractions.
2. Why is it best to assess the mother’s vital signs during the interval between contractions?

12. Respiratory System Changes
During labor a woman is likely to hyperventilate causing:
Tingling in hands and feet
Numbness
Dizziness
3. What are nursing interventions to alleviate hyperventilation during labor?
Have the woman slow her breathing, breath into her hands or a paper bag.

13. Gastrointestinal System Changes
Most woman are limited to clear liquids or NPO during the labor process.
Gastric motility and digestion of food is reduced.
Decrease risk of aspiration
Why?
4. Why is a woman placed on clear liquids or NPO during labor?

14. Urinary System Changes
Reduce sensations of needing to void
Intense contractions
Anesthesia
Unaware of having a Full bladder
5. Why is the woman prone to a full bladder? What are the consequences of a full bladder during labor?
Inhibit fetal descent or (increased discomfort if no anesthesia)

15. Hematopoietic System EBL = Estimated blood loss
Vaginal delivery ~ 500ml
cesarean birth ~1000ml
Clotting factors are elevated and Fibrinolyis is decreased to promote coagulation at the placental site

16. Passenger
Essential
Factors in
Labor
Powers
Passageway
Psychological

17. THE
POWERS

18. Major Powers Involved Primary Force: Secondary Force:
Involuntary Uterine Contractions or
Muscular contractions which lead to dilation and effacement in the First Stage of Labor
Secondary Force:
Voluntary Uterine Contractions or
Abdominal muscles assist in the Second Stage of Labor with pushing. Increase intra-abdominal pressure to aid in expulsive forces
5. What are the primary and voluntary forces of labor? P.3 18

19. THE
PASSAGEWAY

20. THE PELVIS
Determine if the pelvic cavity is of adequate size to allow for the passage of the full term infant
Optimum shaped pelvis is Gynecoid
See pg. 322 for pelvic shapes.

21. THE PELVIS False Pelvis True Pelvis Represents
Supports the weight of the uterus
Shallow basin above the inlet or brim
True Pelvis
Represents
the bony
limits of the
birth canal
6. Differentiate between the terms true pelvis and false pelvis. p. 322 & 323

22. True Pelvis vs False Pelvis
Inlet - upper margin of symphysis pubis to the upper margin of sacrum
Midpelvis - level of the ischial spines
Outlet - Lower pubic bone to tip of coccyx This area is the smallest portion that the baby must travel through.
7. Differentiate between the inlet, the midpelvis, and the outlet of the true pelvis?

23. Station- degree that the presenting part has descended into the pelvis
in relationship to ischial spines.
Goal: Move from
– to + stations
9. What is station? How is station determined and measured? Does the station need to be a + or – for delivery?

24. Engagement
Descent of the fetal presenting part in relation to the ischial spines of the maternal pelvis = 0 station.

25. Engagement
Engagement
-largest diameter of presenting part has passed through the pelvic inlet
Assessed during
vaginal exam
Ballotable
8. What is engagement? How is it determined?
Engaged

26. THE
PASSENGER
And
PPRESENTATION

27. Fetal Head
Because of its size and rigidity, the fetal head has a major impact on delivery.
The bones are not firmly united. There are sutures between the bones that allow them to overlap or MOLD to the birth canal.
Head also can rotate, flex, and extend
8. Compare the bones, suture lines and fontanels of the fetal head. What do the bones of the fetal head do to accommodate the birth canal? p. 324.

28. Fetal Lie
Relationship of the long axis of the fetus to the long axis of the mother.
Longitudinal Lie Transverse Lie
9. Define the term "fetal lie". What is the difference between transverse lie and longitudinal lie. Which is the most favorable for a vaginal delivery? P. 324

29. Attitude Relationship of fetal body parts to each other Optimum
attitude is
flexion or
ovoid
10. What is fetal attitude? What is the normal fetal attitude? p. 324

30. Fetal Presentation
The portion of the fetus that enters the pelvis first
Three Types:
Cephalic
Breech
Shoulder
11. Define the term "fetal presentation" and explain the difference between the following presentations: p. 325.
cephalic presentation
Vertex
Military
Brow
Face
breech presentation

31. Reference Points of Presentation Cephalic = Head
Vertex, Military, Brow, Face
Breech = Buttock or Foot
Frank, Full, Footling
Shoulder = Transverse lie
p. 325

32. Cephalic Presentations

33. Breech Presentations

34. Position
12. What is fetal position? Explain the position indicated by the letters: p. 325 & 325
LOA
ROA
LOP
ROP
Fetal position describes the location of the fixed reference point on the presenting part in relation to the four quadrants of the maternal pelvis.
R= right, L= left, O= occiput, A=anterior, P=posterior.
13. What is the reference point for a vertex presentation? Occiput
14. What is the reference point for a breech presentation? Sacrum

35. Position
Relationship of the Fetal Presenting Part to the Maternal Pelvis
Steps:
1. Determine the Presenting Part
2. Divide the mothers pelvis into 4 imaginary quadrants A 12 R L 9 3 6 P

36. Test Yourself
Overlapping of the fetal skull to facilitate its passage through the bony pelvis is ___________.
Relationship of fetal body parts to each other is_____________.
Head first presentation is_________________.
Relationship of the fetal spine to the maternal spine is ________________.
Term that refers to the part of the fetus that enters the pelvic inlet first is _____________.

37. THE
PSYCHOLOGICAL

38. BREAK THE CYCLE ! FEAR TENSION PAIN
15. How does anxiety, fear, and fatigue physiologically affect the process of labor? P
PAIN

39. CAUSES OF LABOR Increase in Estrogen Decrease in Progesterone
Page 328
High levels of
Prostaglandins
Degeneration of
Placenta
Over-distention of
Uterus

40. Premonitory Signs of Labor
The impending signs
that take place the last
several weeks of
pregnancy or even the
last several days
Pg. 328 & 329

41. Premonitory Signs of Labor
Lightening
False Labor Pain (Braxton Hicks)
Bloody Show
Increased clear vaginal secretions
Small weight loss (~3 pounds)
Sudden increase in energy

42. True vs False Labor TRUE LABOR FALSE LABOR Contractions are:
* Irregular
* No change or decrease
with walking
* Contractions felt in
abdomen above
umbilicus:
Braxton Hicks
No change in cervix
TRUE LABOR
Contractions are:
* Regular
* Increase in intensity and
duration with walking
* Felt in lower back,
radiating to lower portion
of abdomen
Dilation and effacement
Fetus usually engaged
Progressive changes in the cervix
Pg. 329

43. Phases and Stages of Labor
Stage 1: cm.
Phase 1 - Latent - dilate cm.
Phase 2 - Active - dilate cm.
Phase 3 - Transition - dilate cm
Stage 2: From complete dilation and
effacement to delivery of the baby
Stage 3: From delivery of baby to the
delivery of the placenta
Stage 4: the first hour after delivery
21. Define the first stage of labor. P. 329.
22. What are the three phases of the first stage of labor?
23. What are the characteristics of each of each of these three phases in terms of cervical dilation, uterine contractions, and maternal behavior?

44. Signs of Second Stage of Labor
Complete dilatation of cervix
Urge to bear down
Perineum begins to bulge, flatten
Increase in bloody show
Rectal pressure
Labia begins to part with each contraction
24. Define the second stage of labor and the maternal behavior associated with this stage. P. 333.

45. Mechanisms of Labor/ Cardinal Movements
Descent
Flexion
Internal Rotation
Extension
External Rotation
25. Explain the positional changes /cardinal movements of stage 2 and why they occur in this order? Pg. 330 & 331
Expulsion

46. Signs of Stage Three of Labor
Globular
Shape of Uterus
Fundus Rise in Abdomen
Sudden Gush of Blood
Protrusion of Umbilical cord
25. What is the third stage of labor and what are the signs that indicate placental separation? P. 333.

47. Placenta
Fetal side (Schultze)
Maternal side (Duncan)

48. Forth Stage of Labor
Recovery period after delivery and bonding with the newborn.
Last from 1- 4 hours.
26. Define the fourth stage of labor and the maternal behavior associated with this stage. P. 333.

49. When To Go To The Hospital
Regular uterine contractions
Rupture of Membranes (ROM)
Red vaginal Bleeding
Decreased Fetal Movement
Other concerns

50. Nursing Care Establish Relationship Nursing Assessment:
Maternal and Fetal
Interview
Interventions during labor and birth.
Intrapartum assessment guide pg

51. Leopold’s (1 of 4) Technique for Assessing Fetal Presentation and Position
Standing on the right side, face the woman and palpate with the palms of the hands.
Step 1 - Start at upper fundus and palpate for the head or buttocks
Pg. 342

52. Leopold’s (2 of 4)
Step 2 - Go down each side and locate smooth back or “lumpy” extremities.

53. Leopold’s (3 of 4)
Step 3 - Gently grasp lower portion of uterus and feel for the head or buttock

54. Leopold’s (4 of 4)
Step 4 - Turn and face the woman feet, using both hands palpate lower abd. for cephalic prominence or brow.

55. Ausculation Assess for the area of greatest intensity of the FHR.
Usually best heard at the fetal back

56. Vaginal Examination Presentation – presenting part (head/buttock)
Position – fetal head (OA, OP etc.)
Dilation - enlargement & widening of os (cm)
Effacement – thinning of the cervix (%)
Condition of Membranes – ruptured or intact

57. Vaginal Examination – cont’d
Station- degree that the presenting part has descended into the pelvis. Relationship to ischial spines
(ballotable, -, 0, +)
Engagement - largest diameter of presenting part has passed through the pelvic inlet

58. Amniotic Membranes Intact Ruptured Color Amount Odor SROM AROM Clear
Yellow
Meconium
Amount
Odor

59. Duration of Labor Resistance of the Cervix
Presentation and position of the fetus
The woman’s pelvis
Preparation and relaxation of the mother
Primigravida - up to 22 hrs; average 12 1/2 hrs
Multigravida hrs; average 10 hrs.

60. The End
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