Cephalo pelvic disproportion (Сpd)

CPD either due to :-

The baby’s head is proportionally too large
the

Causes :-

Large baby due to:
Hereditary factors
Diabetes
Postmaturity (still pregnant after due date

Contracted Pelvis

Contracted Pelvis

Definition:
Anatomical definition: It is a pelvis in which one or

Factors influencing the size and shape

of the pelvis:
Developmental factor: hereditary or congenital.
Racial

Etiology of Contracted Pelvis

Causes in the pelvis
Developmental (congenital):
Smal gynaecoid pelvis (generally

Naegele’s pelvis: absence of one sacral ala
Robert’s pelvis: absence of both

Causes in the pelvis
Metabolic:
Rickets.
Osteomalacia (triradiate pelvic brim).
Traumatic: as fractures.
Neoplastic: as osteoma.
Infection

Causes in the spine
Lumbarkyphosis
Lumbar scoliosis
Spondylolisthesis:
The 5th lumbar vertebra with the above vertebral

Causes in the lower limbs
Dislocation of one or bothfemurs.
Atrophy ofone or

Pelvis

History
Rickets: is expected if there is a history of delayed walking

Examination
General examination:
Gait: abnormal gait suggesting abnormalities in the pelvis, spines or

Examinat ion
General examination:
Manifestations of rickets as:
square head
rosary beads in the costalridges.
pigeon

Abdominal examination:
Nonengagement of the head:
in the last 3-4 weeks in primigravida.
Pendulous abdomen:
in

Pelvimetry :
It is assessment of the pelvic diameters and capacity done at

Pelvimetry:
2.Imaging pelvimetry:
X-ray.
Computed tomography (CT).
Magnetic resonance imaging (MRI) .
N.B. CTand MRI are

Internal pelvimetry

is done through vaginalexamination
1. The inlet:
Palpation of the forepelvis (pelvicbrim):
The index

Internal pelvimetry

2.The cavity:
Height, thickness and inclination of the symphysis.
Shape and inclination

2.The cavity:
d.Ischial spines:
Whether it is blunt (difficult to identify at all), prominent

2.The cavity:
e.Interspinous diameter: By using the 2 examining fingers, if both

3- The outlet:
Subpubic angle: Normally, it admits 2fingers.
Mobility of the coccyx:

External pelvimetry

Thom’s, Jarcho’s or crossing pelvimeter can be used for external

Radiological pelvimetry

Lateral view:
The patient stands with the X-ray tube on one side and

Cephalometry

Ultrasonography: is the safe accurate and easy method and can detect:
The

Cephalopelvic disproportion tests

These are done to detect contracted inlet if the head

(2) Muller - Kerr’s method:
It is more valuable in detection of

Degrees of Disproportion

Minor disproportion:
The anterior surface of the head is in

Degrees of Contracted Pelvis

Minor degree: The true conjugate is 9-10 cm.

Management

depends mainly on the degree of disproportion

Minor

vaginal delivery

Moderate

trial labor, if failed

Trial of Labour

It is a clinical test for the factors that

Procedure :

Trial is carried out in a hospital where facilities for

Indications of trial of labour:

Young primigravida of good health.
Moderate disproportion.
Vertex presentation.
No

Termination of trial of labour:

Vaginal delivery: either spontaneously or by forceps if

Indications of caesarean section in contracted pelvis

Moderate disproportion if trial of labour is

Complications

Maternal

Fetal

Contracted pelvis

Maternal:
During pregnancy:
Incarcerated retroverted gravid uterus.
Malpresentations.
Pendulous abdomen.
Nonengagement.
Pyelonephritis especial y in high assimilation

Complications of Contracted Pelvis

During labour:
Inertia, slow cervical dilatation and prolonged labour.
Premature rupture

Foetal:
Intracranial haemorrhage.
Asphyxia.
Fracture skull.
Nerve injuries.
Intra-amniotic infection.

Complications of Contracted Pelvis