Download - Contracted Pelvis by KABERA Rene
CONTRACTED PELVIS
KABERA René,MD Resident- PGY II Ruhengeri Hospital Family and Community Medicine National University of Rwanda
Plan
� Introduction
� Definition
� Types of Pelvis
� Risk factors
� Diagnosis
� Management
� References
10/5/2010 Contracted Pelvis
Introduction
Knowledge of the shape and dimensions of the
normal female pelvis is essential for a proper
understanding of the second stage of labour and its
abnormalities since the body pelvis is an important
component which determines the birth canal
structure.
10/5/2010 Contracted Pelvis
Definition
� Anatomical definition: It is a pelvis in which
one or more of its diameters is reduced below
the normal by one or more centimeters.
� Obstetric definition: It is a pelvis in which
one or more of its diameters is reduced so
that it interferes with the normal mechanism
of labour.
10/5/2010 Contracted Pelvis
Major types of pelvis
Anthrapoid Android
Gynecoid
Platypelloid 10/5/2010 Contracted Pelvis
Risk factors
� Factors influencing the size and shape of the pelvis
� Developmental factor: hereditary or congenital.
� Racial factor.
� Nutritional factor: malnutrition results in small pelvis.
� Sexual factor: as excessive androgen may produce android pelvis.
� Metabolic factor: as rickets and osteomalacia.
� Trauma, diseases or tumors of the bony pelvis, legs or spines.
10/5/2010 Contracted Pelvis
Diagnosis
History
� Trauma or diseases: of the pelvis, spines or
lower limbs.
� Bad obstetric history: e.g. prolonged labour
ended by difficulty; forceps, caesarean
section or still birth.
10/5/2010 Contracted Pelvis
Diagnosis
Examination
General examination
� Abnormal gait.
� Stature: women < 150 cm.
Abdominal examination
� Pendolous abdomen in primigravida.
� Non engagement in last 3-4 wks of pregnancy
in primigravida.
10/5/2010 Contracted Pelvis
Diagnosis
Pelvimetry
� External pelvimetry is of little value as it measures diameters of the false pelvis.
� Internal pelvimetry (done by per vagina exam)
� The inlet:
� Palpation of the forepelvis (pelvic brim): V-shaped depression.
� Diagonal conjugate: <11.5 cm (not used if the head is engaged).
10/5/2010 Contracted Pelvis
Forepelvis
Diagnosis
Diagonal conjugate 10/5/2010 Contracted Pelvis
Diagnosis
� The outlet:
� Bituberous diameter : ≤8 cm
� Mobility of the coccyx: fixed
10/5/2010 Contracted Pelvis
Management
The true
conjugate
Bituberous
diameter
Decision
> 9 > 8 cm Vaginal delivery
8-9 cm > 8 cm Trial of labour
8-9 cm ≤ 8 cm C-section
< 8 cm > or < 8cm C-section
N.B: The fetal measurements must be considered!!! 10/5/2010 Contracted Pelvis
References
� Geneva Foundation for Medical Education
and Research, Contracted Pelvis, Obstetrics
Simplified - Diaa M.EI-Mowafi.2009
� Williams Obstetrics .Section IV. Labor and
Delivery. Chapter 20. Dystocia: Abnormal
Labor, 22nd ed. 2005.
� Current Obstetrics and Gynecologic diagnosis
and treatment. Section III Pregnancy at risk.
Abnormalities of the passage, 9th ed. 2003.
10/5/2010 Contracted Pelvis
� Thank you
10/5/2010 Contracted Pelvis