Labor and delivery involves three stages: 1) The first stage begins with contractions and ends with full cervical dilation. It includes early latent and active phases of dilation. 2) The second stage begins at full dilation and ends with baby's delivery. It involves baby's descent and delivery. 3) The third stage begins after delivery and ends with placenta delivery, usually within 30 minutes but sometimes requiring intervention.

1. Labor and delivery

2. DEFINITION
•Labor is a physiologic process during which the
products of conception (i.e., the fetus, membranes,
umbilical cord, and placenta) are expelled outside of
the uterus
•i.e. culmination of pregnancy
•Effacement and dilatation of the uterine cervix is a
result of rhythmic uterine contractions of sufficient
frequency, intensity, and duration.

3. •The onset of labor is defined as regular, painful
uterine contractions that becomes more
frequent and stronger resulting in progressive
cervical effacement and dilatation.
•Cervical dilatation in the absence of uterine
contraction suggests cervical insufficiency,
whereas uterine contraction without cervical
change does not meet the definition of labor.

4. Effacement and dilatation of the cervix
•Cervical dilation is the opening of the cervix
during childbirth or in other conditions like
miscarriages/abortion.
•Effacement is the thinning and shortening of the
cervix that occurs during labor

5. Dilatation progress
•Latent phase: 0-3 centimeters
•Active Labor: 4-7 centimeters
•Transition: 8-10 centimeters
•Complete: 10 centimeters.
Delivery of the infant takes place shortly after
this stage is reached

6. Effacement

7. Effacement and dilatation

8. Stages of Labor
Obstetrician have divided labor into 3 stages that
delineate milestones in a continuous process.
•First stage (Dilatation stage)
•Second stage (Descent and delivery of the baby)
•Third stage (Delivery of placenta and membranes)

9. First stage of labor
•The first stage begins with regular uterine
contractions and ends with complete
cervical dilatation at 10 cm.
Divided into:
•Latent phase( 0-3cm dilatation)
•Active phase (4-10cm dilatation)

10. •The latent phase begins with mild, irregular
uterine contractions that soften and shorten the
cervix. The contractions become progressively
more rhythmic and stronger.
•This is followed by the active phase of labor, which
usually begins at about 3-4 cm of cervical dilation
and is characterized by rapid cervical dilation and
descent of the presenting fetal part.

11. Friedman curve

12. Second stage
•The second stage begins with complete cervical
dilatation and ends with the delivery of the fetus.
•Stage of descent and delivery of the baby.
•Normally takes 2hrs.
•If it takes longer then 2hrs is should be considered
prolonged.

13. Prolonged second stage
Risk factors associated with a prolonged second
stage include
•nulliparity,
•increasing maternal weight and/or weight gain,
•use of regional anesthesia,
•fetal occiput in a posterior or transverse
position, and
•increased birth weight

14. Third stage of labor
•The third stage of labor is defined by the time period
between the delivery of the fetus and the delivery of
the placenta and fetal membranes.
•Although delivery of the placenta often requires less
than 10 minutes, the duration of the third stage of
labor may last as long as 30 minutes.

15. Management of third stage
Aims at;
• Shortening of the third stage
• Minimize blood loss
Expectant/passive management of the third stage
of labor involves spontaneous delivery of the
placenta

16. Active management
• Involves :
•prophylactic administration of oxytocin or other
uterotonics (prostaglandins or ergot alkaloids),
•early cord clamping/cutting, and
•controlled cord traction of the umbilical cord.

17. A systematic review of the literature
reveals that that active management
shortens the duration of the third stage
and is superior to expectant
management with respect to blood
loss/risk of postpartum hemorrhage

18. Duration of third stage
•The third stage of labor is considered
prolonged after 30 minutes, and active
intervention, such as manual extraction
of the placenta, is commonly considered

19. Mechanism of normal Labor
• The ability of the fetus to successfully negotiate the
pelvis during labor involves changes in position of its
head during its passage in labor.
• The mechanisms of labor, also known as the cardinal
movements, are described in relation to a vertex
presentation, as is the case in 95% of all pregnancies

20. Criteria for normal labor.
• Spontaneous in its onset and at term
• With vertex presentation
• Without prolongation
• Natural termination with minimum aids
• Without having complications affecting the health of the
mother and/or the baby.
-Any deviation from these criteria is an abnormal labor.

21. 1. Engagement
• The widest diameter of the presenting part (with a
well-flexed head, where the largest transverse
diameter of the fetal occiput is the biparietal diameter)
enters the maternal pelvis to a level below the plane
of the pelvic inlet.
• On the pelvic examination, the presenting part is at 0
station, or at the level of the maternal ischial spines

22. 2. Descent
The downward passage of the
presenting part through the pelvis. This
occurs intermittently with contractions.
The rate is greatest during the second
stage of labor.

23. 3. Flexion
As the fetal vertex descents, it encounters resistance
from the bony pelvis or the soft tissues of the pelvic
floor, resulting in passive flexion of the fetal occiput.
The chin is brought into contact with the fetal thorax,
and the presenting diameter changes from
occipitofrontal (11.0 cm) to suboccipitobregmatic (9.5
cm) for optimal passage through the pelvis

24. Internal rotation
• As the head descends, the presenting part, usually in
the transverse position, is rotated about 45° to
anteroposterior (AP) position under the symphysis.
• Internal rotation brings the AP diameter of the head in
line with the AP diameter of the pelvic outlet.

25. Extension
With further descent and full flexion of the head, the
base of the occiput comes in contact with the inferior
margin of the pubic symphysis. Upward resistance from
the pelvic floor and the downward forces from the
uterine contractions cause the occiput to extend and
rotate around the symphysis. This is followed by the
delivery of the fetus' head.

26. Restitution and external rotation
When the fetus' head is free of
resistance, it untwists about 45° left or
right, returning to its original anatomic
position in relation to the body.

27. Expulsion
After the fetus' head is delivered, further
descent brings the anterior shoulder to the
level of the pubic symphysis. The anterior
shoulder is then rotated under the
symphysis, followed by the posterior
shoulder and the rest of the fetus.

28. Mechanisms of labor.

29. Engagement and descent

30. flexion

31. Internal rotation

32. extension

33. Deliv..ant shoulder