2. CEPHALOPELVIC DISPROPORTION (CPD)
Cephalopelvic disproportion exists when the capacity of the
pelvis is inadequate to allow the fetus to negotiate to allow the
birth canal.
This may be due to a small pelvis , a nongynecoid pelvic
formation , a large fetus , an unfavourable orientation of the
fetus or combination of these factors.
Certain medical conditions may distort pelvic bones such as
rickets or a pelvic fractures.
3. CAUSES
Large fetus can be one cause of CPD. A large fetus can be
caused by gestational diabetes , post term pregnancy , genetic
factors and multiparity.
The shape of the pelvis can also be a cause of CPD. The pelvis
may be too small , or shape of the pelvis may be malformed .
Shorter women are more likely to suffer from CPD.
4. DIAGNOSIS
Diagnosis of CPD may be made when there is failure of
progress , but not all cases of prolonged labour are the result of
CPD.
Use of ultrasound to measure the size of the fetus in the womb is
controversial , as these methods are often inaccurate and may
lead to unnecessary caeserian section ;
A trial of labour is often recommended even if size of the fetus is
estimated to be large.
5. TREATMENT -
In case of a fetus being too large , some obstetricians
recommend induction of labour for earlier delivery .
Diagnosis of CPD in active labour will usually result in a
caeserian section .