UNIT XIV
Trial of labour (TOL)
Definition : It is the conduction of spontaneous labour in a moderate degree of cephalo –pelvic
disproportion, in an institution under supervision with watchful expectancy ,hoping for vaginal
delivery.
Every arrangement should be made available for operative delivery, either vaginal or
abdominal ,if the condition so arises.
USG or maternal pelvimetry may be done before TOL to rule out CPD. The cervix must
be soft and dilatable during TOL. During TOL the woman is evaluated for the occurance
of active labour.
Aim
The aim of the TOL is to avoid caesarean section and a delivery of a healthy baby.
Suitable for trial of labour
Young primigravida for good health
Disproportion
Vertex presentation
No outlet contraction
Average sized baby
Contraindication
Associated mid-pelvic and outlet contraction
Pregnancy with complicating factors like elderly primigravida, malpresentation, post
maturity, post c/s, pre eclampsia, medical disorder such as heart
disease ,diabetes ,tuberculosis etc. etc.
Where the facilities of caesarean section is not available round the clock.
IUGR
Guidelines for management of labour
Management of trial of labour requires careful supervision and consideration.
o The labour should ideally be spontaneous in onset. But in those cases where the
labour fails to start even at due date, induction of labour may be contempleted.
o Oral feeding remains suspended and hydration is maintained by IV drip.
o The progress of labour is meticulously observed periodically by noting
Progressive descent of the fetus
Progressive dilatation of cervix.
If there is failure to progress due to inadequate uterine contraction, augmentation of
labour in carefully selected cases may be done by amniotomy along with oxytocin
infusion.
No any intervention is employed before the cervix is at least 3cm.
Watch maternal and fetal condition carefully.
After the membrane rupture, pelvic examination is to be done
o To exclude cord prolapse
o To note the colour of liquor
o To assess the pelvis once more
o To note the condition of the cervix including rate of descent and pressure of the
presenting part on the cervix.
Facilitated place with provison of C/S ad post C/S management.
Successful Outcome OF Trial of labour
The outcome of any labour is depends on
Degree of pelvic disproportion
Shape of the pelvis
Favourable vertex presentation
Intact membrane till full dilatation of the cervix
The effectiveness of uterine contraction
The degree of moulding of fetal head.
Tolerance of patient.
Unfavourable features
Appearance of abnormal uterine contraction
Early rupture of membrane
Cervix becoming thick and edematous
Formation of caput and evidence of moulding more than normal
Fetal distress.
Termination of TOL
Augumentation of labour
Spontaneous vaginal delivery with or without episiotomy.
Forceps or vacuum delivery- difficult forceps must be avoided.
Caesarean section for uterine inertia or fetal disteress.
Indication of C/S
CPD: moderate disproportion if trial of labour fails or contraindicated.
Extreme disproportion whether the fetus is dead or living.
Outlet contracted pelvis with other indication such as malpresentation, primigravida,
placenta previa.
Advantages
It eliminates unnecessary C/S electively decided upon.
It eliminates injudicious use of premature induction of labour with its antecedents
hazards.
A successful trial ensures the woman a good future obstetrics
Disadvantages
Increased perinatal mortality or morbidity due to asphyxia or intracranial haemorrhage
when the trial is prolonged/ end in difficult labour.
Increased maternal morbidity due to effects of prolonged labour and/or operative
delivery.
Management during TOL
The woman should not be told that there is uncertainly as to the mode of delivery, as it
may undermine her confidence as she may not be able to cooperate fully.
Labour should preferably be spontaneous and not induced.
As soon as the membranes rupture, the woman may be examined vaginally to see the
colour of the liquor and exclude prolapse of the cord.
Observe adequately for
o Maternal pulse, BP, and temperature
o Fluid balance chart
o Urine for acetone
o Fetal heart rate
o Uterine contraction and progress of labour
Labour must be monitored by using partograph.
Adequate hydration/nutrition should be maintained by IV drip.
Prepare for emergency C/S when indicated.
Successful trial
A trial is called successful, if a healthy baby is born vaginally, spontaneously or by
forceps or ventous with the mother in a good condition.
Unsuccessful trial
A trial is called unsuccessful when delivery by caesarean section or delivery of a dead baby
spontaneously or by craniotomy.
