UNDERGRADUATE COURSE LECTURES IN OBSTETRICS&GYNECOLOGY PREPARED BY DR MANAL BEHERY PROFESSOR OB&GYNE FACULTY OF MEDICINE ZAGAZIG UNIVERSITY

1. Normal labor
DR MANAL BEHERY
PROFESSOR OB&GYNE
ZAGAZIG UNIVERSITY
2019

2. Definition of normal labor
• Normal labour is contractions of the gravid
uterus that expel the fetus and the other
products of conception
• between 37 and 42 weeks from the last
menstrual period (Term Delivery)

3. Preterm labour：Preterm labor is that occurring
before 37 weeks of gestational age.
Postdate pregnancy：Postdate pregnancy occurs
after 42 weeks .

4. Criteria for normal labour
1. Spontaneous expulsion,
2. Of a single,
3. Mature fetus (37. completed weeks-42. weeks),
4. Presented by vertex,
5. Through the birth canal (vaginal delivery),
6. Within a reasonable time (more than 3, less than
18 hours),
7. Without complications to the mother,
8. Without complications to the fetus.

5. Influencing factors
 The 3 „P”: (progress of labor)
 Power: uterus (myometrium)
 Passenger: fetus (head mostly)
 Passage: (pelvis of the mother)

6. True Labor is
Uterine Contractions that cause-
–Progressive dilation and effacement
of cervix
–Descent of fetus
–Expulsion of fetus
and placenta

7. Cervical dilatation by vaginal examination

8. • Effacemant :is shortening and thining of the
cervical canal (from a length of 3 cm to a circular
aperture.
Effecemant

9. How is station (descent )measured and
recorded?
• -3: 3 cm above the ischial spines
0: at the ischial spines, engaged
+3: 3 cm below the ischial spines

10. Engagement and station of the fetus in
labour

11. Character which define the onset of labor:
 Ruptured membranes
 Bloody „show”
 Complete cervical effacement

12. True labour vs fales labour
• Regular contractions
• Increase in frequency
and intensity
• Cervix dilate
• No relive with
sedation
• Abd and back pain
• Irregular
• Remain the same
• Unchanged
• relive
• Lower abd

13. Stages of labor

 First stage:
 Starts with the onset of true labor contractions
 Ends when the cervix is fully dilated (10cm)
 Longest stage of labor
 Second stage:
 Begins with the complete dilatation of the cervix
 Ends with the birth of the baby
Duration is between 30 and 90 minutes

14. Stages of delivery
 Third stage of labor:
 Separation and expulsion of placenta and
membranes
 Duration is between 5 and 30 minutes
 Shortest stage of labor
 Fourth stage of labor:
 After the expulsion of placenta
 Duration is 2 hours
 Increased risk for bleeding

15. First stage of delivery
 1. Regular contractions
 2. increase in intensity
 3. Increasing in frequency (↑)
 4. increase in duration
 1
causes
Cervical dilatation and effacement

16. First stage of delivery
 Contraction and retraction of uterine muscle
 Mechanical pressure by the membrane
 The descend of the presenting part
 Cervical dilatation and effacement

17. Phases of cervical dilatation:
 Latent phase:
 the first 3 cm of dilatation, it is a slow process
{8 hours at nulliparous, 3 hours at multiparous}
 Active phase:
 faster dilatation, from 3 cm to fully dilatation
(apr. 10cm) {Normal rate is 1 cm / hour}

18. Effacement: thinning of the cervix

19. Effacment of the cervix

20. FRIEDMAN’S CURVE

21. Station

22. 2nd stage of labor – expulsion
of the fetus
 Begins when cervical dilatation is complete
and ends with fetal delivery.
 Median duration 40-60 min for nulliparas
and 20-30 min for multiparas.

23. LOA position

24. How does the head negotiate the
pelvis?
(1) change it’s shape and size
(moulding)
(2) change it’s position (flexion and
rotation)

25. Left occiput position (LOA,
LOT, ROT

26. Cardinal movement of normal labor

39. External rotation

42. The cardinal movements of labor

48. Third stage of labour


 Begins after delivery of the baby and ends with the
delivery of the placenta and membranes
 It contains two phases
 A., Separation
 B., Expulsion
Duration: 5-20minutes (if actively managed)
Blood loss: 150-250 ml (average)

50. NORMAL LABOR VIDEO

51. Video of childbirth

52. Fetal lie
 The relation of the long axis of the fetus to
that of the mother!
 Longitudinal lie (~99%)
 Transverse lie (<1%)
 Oblique lie
unstable and always becomes longitudinal or transverse during
the course of labor

53. Fetal lie – longitudinal axis of the fetus in
relation to the long axis of the maternal uterus. assessed by
abdominal examination prior to delivery.
• Logitudinal transverse oblique
• (unstable)

54. Presentation
*
• the part of the fetus that is presenting or is the
closest in proximity to the birthing canal
• Vertex Breech

55. Presentation
*
• the part of the fetus that is presenting or is the
closest in proximity to the birthing canal
• Vertex Breech

57. Incidences of fetal presentation
 Cephalic
 Breech
 Transverse
 Compound
 Face
 Brow
96,8 %
2,7 %
0,3 %
0,1 %
0,5 %
0,01 %

58. Fetal attitude or posture
 The fetus becomes folded upon itself:
 the back becomes markedly convex,
 the head is sharply flexed,
 the thighs are flexed over the abdomen,
 the legs are bent at the knees,

59. Fetal position
According to the determinig points:
 the fetal occiput (vertex) – left or right
occipital,
 the fetal face (mental) – left or right mental,
 breech (sacrum) – left or right sacral
 shoulder (scapula is the arbitrarily chosen
for orientation)
presentations.

60. There are six varieties of each
of the three presentations

61. Labor with occiput presentations
 Occiput anterior
position (ROA)
 Occiput transverse
position (ROT)
 Occiput posterior
position (ROP)

62. LOA position

63. Us for detection of position