1. RELATION BETWEEN FETUS & PELVIS

2. LIE
PRESENTATION
PRESENTING PARTS
ATTITUDE
DENOMINATOR
POSITION
CEPHALIC PROMINENCE

3. LIE
The relationship b/w the long axis of fetal ovoid to the long axis of uterine ovoid
LONGITUDINAL LIE
TRANSVERSE LIE
OBLIQUE LIE

5. PRESENTATION
That part of the fetus that lies over the pelvic inlet & occupies the lower poles of the uterus
3 presentation
CEPHALIC
PODALIC/BREECH
SHOULDER

7. PRESENTING PARTS
The most dependant part of the fetus,
which is felt first on vaginal examination
In cephalic presentation depending upon degree of flexion,
vertex
brow
face
deflexed head

8. In breech presentation
Flexed breech (fetal legs may be flexed)
Extended breech (extended at knees)
Footling breech (completely extended)

10. ATTITUDE
The relation of fetal parts to each other
Main attitudes
FLEXION
EXTENSION

11. TYPICAL FETAL ATTITUDE
universal flexion with head flexed over chest, arms & legs flexed in front of the body and back curved forward

12. Anteroposterior diameters of the fetal skull
AP diameter
Attitude
Presenting part
Suboccipitobregmatic 9.4 cm
Complete flexion
Vertex occipitoanterior
Suboccipitofrontal 10.5 cm
Incomplete flexion
Vertex occipitoposterior
Occipitofrontal 11 cm
Deflexion
Verticomental 13.5 cm
Extension
Brow
Submentobregmatic 9.4 cm
Complete extension
face

14. DENOMINATOR
An arbitrarily chosen point on the presenting part of the fetus which is used to describe the position.

15. Presentations of the fetus
Attitude
Denominator
Cephalic
vertex occipitoanterior
Flexion
Occiput
vertex occipitoposterior
Deflexion
occiput
brow
Extension
face
Complete extension
Chin or mentum
Podalic or breech
sacrum
shoulder
acromion

16. Frequency of lie and presenting part
Presentation and presenting part
Longitudinal 99.5%
Vertex %
Transverse or oblique 0.5%
Face %
Brow %
Breech 3%
Shoulder 0.5%

17. POSITION
The relationship of the denominator to the four quardrants of the maternal pelvis.

18. In vertex presentation
Left occipitoanterior(common)
Left occipitotransverse
Left occipitoposterior
Right occipitoanterior
Right occipitotransverse
Right occipitoposterior

20. Occipitoanterior

21. Left occipitoposterior

22. LeftOccipitoanterior

23. LeftOccipitotransverse

24. Occipitoposterior

25. CEPHALIC PROMINENCE
The most prominent part of the head palpable per abdomen
Produced by flexion and extension of the head
Vertex presentation (head well flexed)
occiput is lower than sinciput (can be felt on the side opposite to the back)

26. When the presenting part is face or brow (extension of head)
sinciput is lower than occiput (can be felt on the same side of the back)
Cephalic prominence can be palpated by the second pelvic grip

27. When no cephalic prominence is felt, there is neither flexion nor extension and the attitude is one of deflexion . This is also called military position

28. Longitudinal lie commoner –fetus being an ovoid accommodates itself easily along the long axis of the uterine ovoid
Cephalic presentation commoner -the head being heavier and more compact , due to gravitation, comes to occupy lower pole and bulkier breech adapts to the fundus of uterus ,which is roomier

29. MOULDING
Cranial bones are connected by membrane and this allows considerable shifting or sliding of each bone to accommodate to the maternal pelvis.
Frontal and occipital bone pass under parietal bone.
Posterior parietal is subject to more pressure by the sacral promontory , it passes under anterior parietal.

30. MOULDING (conti…..)
Thus there is compression of the presenting diameter with compensatory bulging of the diameter at right angles
Eg: in occipitoanterior head is compressed in the presenting suboccipitobregmatic and elongated in the verticomental diameter .

31. Moulding is assessed on vaginal examination at two sites
parietal-parietal
parietal-occipital
disappears a few hrs after birth
Protective mechanism & prevents the fetal brain from compression as long as it is not excessive or not rapid

32. GRADING
Grade 1 / +moulding :obliteration of suture line
Grade 2 / ++moulding : reducible overlap
Grade 3 /+++moulding:irreducible overlap (pathological)

33. Clinical significance
Some amount of moulding is beneficial and this is one of the factors which decide the success of a trial of labour
Severe moulding can lead to intracranial haemorrhage
The site of moulding gives information about the position of the head

34. Thank you