CONTRACTED PELVIS

DEFINITION A contracted pelvis may be defined as one in which there is alteration in the size and shape of the pelvis of sufficient degree so as to alter the normal mechanism of labour in an average size baby.

ETIOLOGY NUTRITIONAL AND ENVIRONMENTAL DEFECTS Rachitic - a flat pelvis distorted as a result of rickets. Osteomalacic- Softening of the bones, typically through a deficiency of vitamin D or calcium.

DISEASES OR INJURIES AFFECTING THE BONES OF THE PELVIS Fracture, tumour, TB, poliomyelitis, hip joint disease DEVELOPMENTAL DEFECTS Naegele’s pelvis-It is produced due to arrested development of one ala of the sacrum

Robert’s pelvis- Ala of both sides are absent and sacrum is fused to the innominate bone Kyphotic pelvis a deformed pelvis associated with a kyphotic deformity of the spine.

DIAGNOSIS Medical history- Fracture, tumour, TB, poliomyelitis, hip joint disease Obstetric history Previous prolonged labour Previous still birth Baby born with asphyxia History of neonatal convulsion and mental retardation Instrumental delivery Maternal injury Appearance of the patient

Contd…. Contracted pelvis should suspected in following cases Small stature Pendulous abdomen Exaggerated spinal curvature Deformities of the limb

Contd…. ABDOMINAL EXAMINATION Posterior position – common Pendulous abdomen Badly flexed head VAGINAL EXAMINATION CLINICAL PELVIMETRY

HAZZARDS radiation exposure to the mother and the fetus

CEPHALOPELVIC DISPROPORTION The disparity in the relation between the head and the pelvis is called CPD

DIAGNOSIS Clinical- Abdominal and Abdomino-vaginal method Imaging pelvimetry Cephalometry –USG, MRI, X-ray

MANAGEMENT Preterm induction of labour TRIAL OF LABOUR CAESAREAN SECTION Severely contracted pelvis Elderly primi gravida Breech Previous LSCS Failed trial of labour If disproportion due to fetal cause, Craniotomy Symphysiotomy Manipulative correction

TRIAL OF LABOUR It is the conduction of spontaneous labour in a moderate degree of CPD, in an institution under supervision with watchfull expectancy, hoping for a vaginal delivery

Aims – avoiding unnecessary CS and at delivering a healthy baby Contraindications midpelvic and outlet contraction Complicating factors like elderly primigravida, malpresentation, postmaturity, post CS, pre-eclampsia, medical disorders Facilities of CS is not available

Conduction of trial labour Labour should ideally spontaneous Hydration maintained by IV drip Progress of labour is observed-descent of fetus, dilatation of cervix No procedure should be employed before the cervix is at least 3cm dialated Watch maternal and fetal condition After the membranes are ruptured, pv is to be done Cord prolapse Colour of liquor Assess the pelvis and cervix

Successful outcome depends on- Degree of pelvic contraction Shape of the pelvis Favourable vertex presentation Intact membranes till the full dilatation of cervix Effective uterine contractions Tolerance of the patient

Trial labour to be continued till evidence of descent of the head and progressive cervical dilatation and maternal and fetal condition remain good

Termination of trial labour Spontaneous delivery with or without episiotomy Forceps or ventouse Caesarean section Successful trial labour- a healthy baby is born vaginally, spontaneous or by forceps or ventouse with the mother in good condition Advantages – eliminates unnecessary CS Eliminates injudicious use of premature induction of labour Ensures the woman a good future obstetrics

Disadvantages Test of disproportion remains unproven Increased perinatal morbidity or mortality