1. Process and Stages of
Labor and Birth
Chapter 17

2. LABOR The Process by which the Products of Conception are expelled
from the body

3. Critical Factors In
Labor

4. THE
Birth
PASSAGE

5. 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
1. Differentiate between the terms true pelvis and false pelvis.

6. True Pelvis vs. False Pelvis
Inlet - upper margin of pubic bone to
upper margin of sacrum
Outlet - Lower pubic bone to tip of
coccyx. This area is the
smallest portion that the baby
must travel through.
2. Explain the difference between the two main sections of the true pelvis and how they impact delivery of the fetus.
Which of the following is most important in providing a successful delivery? Why?

7. The
Fetus

8. 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
3. 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?

9. Attitude Relationship of fetal body parts to each other Optimum
attitude is
ovoid
4. What is attitude? What is the optimum attitude for delivery?
The head is flexed forward, with the chin almost resting on the chest. The arms and legs are flexed.

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

11. True or False? The optimum lie of the fetus is the longitudinal lie.
A. True
B. False
True

12. Fetal Presentation
That portion of the fetus that enters the Pelvis first and covers the internal os.
Three Types:
Cephalic
Vertex, Face, Brow
Breech
Shoulder
6. Define the term “fetal presentation” and explain difference between presentations.
Cephalic Presentation
The head is entering the pelvis first.

13. Reference Points Cephalic = Occiput, posterior fontanel
Breech = Sacrum
Face = Mentum
7. What reference point would the nurse use when assessing cephalic presentation? A breech presentation? A face presentation?
9. What reference point would the nurse use when assessing breech presentation?

14. Relationship of
Maternal Pelvis
and
Presenting Part

15. 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

16. Station- degree that the presenting part has descended into the pelvis
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?

17. 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
10. What is fetal position? What are the steps in assessing position? A 12 R L 9 3 6 P

18. Test Yourself !
What is the reference point of a cephalic presentation when the head is fully flexed?
A. occiput
B. mentum
C. frontal
d. sagittal

19. 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 _____________.

20. The
Physiologic
Forces of Labor

21. Major Powers Involved
Involuntary Uterine Contractions or Primary Powers
Muscular contractions which lead to dilation and effacement in the First Stage of Labor
Voluntary Uterine Contractions or Secondary Powers
Abdominal muscles assist in the Second Stage with pushing. Increase intra-abdominal pressure to aid in expulsive forces
12. What are the primary and secondary powers/forces of labor?
13. When are the secondary powers used during the labor process?
15. When are the secondary powers used during the labor process?

22. FORCES OF LABOR
Contraction -exhibits a wavelike pattern that begins slowly climbing (increment) to a peak (acme), and decreases (decrement)
acme
Decrement
Increment
Duration
14. Explain the parts of a contraction and the relationship including:
Interval
Frequency
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 for placental perfusion

23. Fill in the Blank Length of a uterine contraction__________.
Strength of a uterine contraction is ___________.
The time from the beginning of one contraction to the beginning of the next contraction is _______.
The time that allows for placental perfusion is __.
The peak of a contraction is also known as ____.
When the biparietal diameter of the head passes through the pelvic inlet it is said to be ________.

24. PSYCHOLOGICAL
Considerations

25. BREAK THE CYCLE ! FEAR TENSION PAIN
18. How can stress and anxiety interfere with the process of labor?
19. What are nursing interventions to assist clients in decreasing anxiety?
PAIN

26. Physiology Of
Labor

27. Progesterone Withdrawal Corticotropin-Releasing Hormone
CAUSES OF LABOR
Progesterone Withdrawal
High levels of
Prostagladins
Corticotropin-Releasing Hormone
20. What are the possible causes of labor onset?

28. Myometrial Activity Effacement- thinning of the cervix (%)
Dilation – enlargement and widening of the os (cm)
21. Define effacement and dilatation and how measured

29. Critical Thinking
If the fetal head did not descend through the pelvis and stayed at the same station for a prolonged period of time, what do you think would be the treatment of choice?

30. Try this ! When the cervical os widens or opens it is said to________.
The level of the ________ _________ is station zero.
The most common type of pelvis for a woman ___________.
When the cervix shortens and thins is _______________.
For delivery to occur, the fetus must accomodate to this rigid passageway______________.

31. Premonitory Signs of Labor
The impending signs
that take place the last
several weeks of
pregnancy or even the
last several days
22. What are the premonitory signs of labor?

32. Premonitory Signs of Labor
LIGHTENING
Braxton-Hicks Contractions
Cervical changes
SHOW
ROM
BACKACHE
SUDDEN INCREASE IN ENERGY

33. True vs. False Labor TRUE LABOR FALSE LABOR Contractions are:
* Regular
*Increase in intensity and duration with walking
*Felt in lower back, radiating to lower portion of abdomen
Bloody show
Dilation and effacement
Fetus usually engaged
FALSE LABOR
Contractions are irregular
Often stop with walking
Contractions felt in abdomen above umbilicus (abdominal pains)
No change in cervix
Fetus is ballotable
23. What assessment findings differentiate true labor from false labor?

34. Phases and Stages of Labor
Stage 1 – From 0 cm. dilated to 10 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

35. Phases of First Stage of Labor
Latent Phase – is from 0 to 3 cm. dilated
Active Phase – is from 4cm. to 7 cm.
Transistion Phase – is from 8 cm. to 10 cm.
24. What are the three phases of the first stage of labor and characteristics of each? (p )

36. Signs of Second Stage of Labor
Complete dilatation of cervix
Urge to bear down
Perineum begins to bulge, flatten and move anteriorly
Increase in bloody show
Rectal pressure
Labia begins to part with each contraction

37. 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?
Expulsion

38. Signs of Stage Three of Labor
Globular
Shape of Uterus
Fundus Rise in Abdomen
Sudden Gush of Blood
Protrusion of Umbilical cord
26. What are the signs in the third stage that indicate that the placenta is ready for delivery? (p. 412)

39. The End