1. The course and conduct of normal labor and delivery

2. A definition of labor
Progressive dilatation of the uterine cervix in association with repetitive uterine contractions.
Spontaneous or induced
Term or preterm

3. Important terms
Lie- relationship between the long axis of the fetus and that of the mother (longitudinal, transverse or oblique).
Presentation- the fetal part that lies closest to the pelvic inlet (cephalic - vertex, face; breech; shoulder).
Attitude- relationship of the fetal parts to each other, usually head and trunk (flexion or extension of the neck).

4. Onset of labor
Regular uterine contractions - from at least 1/2 hr, frequency at least every 10 minutes
Bleeding
Rupture of membranes

5. Stages of the labor I - shortening and dilatation of the cervix
II - delivery of the fetus
III - delivery of the placenta with the umbilical cord and membranes
IV - about two hours after delivery (inspection and surgical help)

6. Duration of the labor

7. Dilatation of the cervix
Nullipara:
I - shortening
II - dilatation of external os
III - dilatation of internal os
Multipara:
phases I, II and III occur together

8. Mechanisms of labor
The special labor mechanisms is due to asymmetry of the shape of both the fetal head and maternal pelvis.
Changes in the position of the fetal head are required for the average size fetus to accomplish passage through the birth canal.
The rotations are accomplished by the propulsive force of uterine activity.

9. Important! Pelvic planes and diameters of the pelvic inlet
Diameters of fetal skull
Leopold’s maneuvers
(Data in each manual of obstetrics)

10. Examination External (Leopold’s maneuvers) Internal
cervix - length and dilatation
membranes - intact or not, color of the amniotic fluid
fetus - presentation, attitude, rotation
pelvis - size

11. Cardinal movements of labor
movements of the head
engagement
descent
1. flexion
2. internal rotation
3. extension
4. external rotation
expulsion

12. Engagement
It is the descent of the largest transverse diameter of fetal head (BPD) to a level below the plane of the pelvic inlet.
Then the head is engaged.

13. Flexion (I movement of the head) - placement of the fetal chin on the thorax
Internal rotation (II movement) - rotation from the transverse position towards symphysis.

14. Extension - III  movement
Begins at the level of maternal vulva
The fetal head is delivered by extension from the flexed to the extended position rotating around the symphysis pubis

15. External rotation - IV  movement
After delivery of the head the forces exerted on the head by the maternal pelvic musculature are relived and the fetus resumes its normal face-forward position.
Its face begins to „look” at one of mother’s leg.

17. Expulsion
Delivery of the shoulders - first the anterior one (under the symphysis pubis) and then the posterior one.
The rest of the body is usually quickly delivered.

18. Assisted spontaneous delivery
Lateral episiotomy
Prevention of rapid delivery of the head
Delivery of the shoulders and body
Aspiration of the mucus from the fetal mouth, pharynx and nose
Cord clamping

19. Episiotomy A lateral incision of perineum before delivery of the head
Why?
to enlarge the area of the outlet  easier delivery of the head  prevention of intraventricular hemorrhage
prevention of lacerations
prevention of late complications - relaxation of pelvic muscles and urine incontinence

20. Episiotomy Prophylactic - nulliparas, some multiparas Mandatory
in instrumental delivery, like forceps or vacuum extractor
in abnormal presentations, like breech
in preterm deliveries

21. Monitoring of fetal well-being
Continuous fetal heart rate and contractions monitoring (CTG) - external or direct
baseline FHR
FHR variability
periodic FHR changes
decelerations (early, late, variable)
accelerations
sinusoidal FHR pattern
Fetal capillary scalp blood sampling

22. Baseline FHR between 110 and 150 bpm
< bradycardia (e.g. hypoxia)
> tachycardia (e.g. infection)

23. FHR variability short-term, a beat-to-beat variability
normal ranges: bpm from the basis
< 5 - loss of variability (silent)
> 25 - exaggerated variability

24. Deceleration Decrease in FHR of at least 15 bpm lasting 15 s or longer
early - begins with the beginning of contraction, reaches its lowest point just with the peak of contraction
late - occurs in the late phase of contraction, its lowest point is after contraction
variable - no association with contractions

25. Deceleration
early - due to pressure of fetal head as it moves down the birth canal, reflex mediated by the vagus nerve
late - result of fetal hypoxia (uteroplacental insufficiency)
variable - effect of umbilical cord compression (cord around the neck, arm or between some part of the fetus and the uterine wall)

26. Acceleration Increase in FHR of at least 15 bpm lasting 15 s or longer
associated with contractions or fetal movements
indicator that fetus is adequately oxygenated

27. Anesthesia for labor Psychoprophylaxis - very important
teaching about physiology
breathing
stress control
husband participation
Narcotic drugs - attention: risk of respiratory depression in newborn
Subarachnoidal block