Abnormal Labour
Normal labour
3 elements,
? expulsive force
? birth canal
? fetus
Abnormal labour
Abnormalities of the expulsive forces
Abnormalities of the fetus
Abnormalities of the maternal pelvis
Abnormal expulsive force
Uterine dysfunction
?hypotonic uterine dysfunction
?hypertonic uterine dysfunction
Hypotonic uterine dysfunction
Effective contraction:
? uterine activity is sufficient to make the
cervix effacement and dilatation,fetus
descent.
Etiology
Cephalopelvic disproportion or fetal
malposition
abnormal uterus
psychological factors
endocrinal dysfunction
excessive sedation or conduction
analgesia
Clinical manifestation
Coordinate hypotonic uterine
dysfunction
incoordinate hypotonic uterine
dysfunction
partogram,World Health Organization
partograph
World Health Organization partograph
A partogram was designed for use in developing
countries (1992).Labour is divided into a latent
phase,which should last no longer than 8hours,and
an active phase starting at 3cm dilatation,the rate of
which should be no slower than 1cm per hour,A 4-
hour wait is recommended before intervention when
the active phase is slow,Labor is graphed and
analysis includs use of alert and action lines,The
protocol was found to be beneficial in Southeast
Asia.(WHO,1994)
7 concepts
Prolonged latent phase:16 hr
prolonged active phase:8 hr
arrest active phase:0cm/2hr
prolonged second-stage labor:2hr/1hr
arrest second-stage labor:0cm/1hr
delayed descent:<1cm/hr
arrest descent:>=0cm/hr
Treatment
Enhance the uterine contractibility
the goal is to affect uterine activity that
is sufficient to produce cervical change
and fetal descent while avoiding uterine
hyperstimulation and fetal distress.
Hypertonic uterine contraction
Localized abnormalities of uterine action
? constriction ring
? pathological retraction ring
? localized rings or constrictions of the uterus develop in
association with prolonged labors,which is often the
result of obstructed labor,with marked streching and
thinning of the lower uterine segment,The ring may be
seen clearly as an abdominal indentationand signifies
impending rupture of the lower uterine segment.
Generalized abnormalities of uterine
action
Precipitate labor:
? extremely rapid-labor
? total duration less than 3 hours
?abnormally low resistance
?abnormally strong uterine and abdominal
contractions
?very rarely,the consequence of painful
sensations and thus a lack of awareness of
vigorous labor.