This document discusses abnormal uterine action during labor, including definitions, types, causes, diagnosis, and management. The main types discussed are uterine inertia, ineffective contractions, abnormal polarity, incoordinate contractions including spastic lower segment and constriction ring, cervical dystocia, precipitate labor, tonic contractions, and retraction ring. The importance of assessing uterine tone, frequency and strength of contractions is emphasized for diagnosis. Management depends on the specific abnormality but may include oxytocin augmentation, amniotomy, operative vaginal delivery, or cesarean section.

1. ABNORMAL
UTERINE ACTION
BY, MS.PRIYANKA GOHIL
M.Sc. (N) OBG
Nursing Tutor, MBNC

2. • Normal labour is characterized by
coordinated uterine contractions
associated with progressive dilation
of cervix and descent of fetal head.
• Associated with cervical dilatation
≥ 1 cm /hr in Nulliparous woman
• Likely to end in successful vaginal
delievery.

3. Normal Uterine Contractions:-
Polarity of Uterus
When the upper segment contracts, the
lower segment relaxes
Pacemakers
There are two pacemakers
situated at each cornua of the uterus
Generates uterine contractions in a
coordinated fashion

4. Properties of Normal Uterine Contractions:-
The intensity of contraction diminishes
from top to bottom of the uterus
The contraction waves starts of the
pacemaker and propogates towards the
lower uterine segment
The duration of contraction diminishes
progressively as the wave moves away
from the pacemaker
In dysfunctional labor, new pacemaker
may come up anywhere in the uterus

5. DEFINITION:-
“Any deviation of the normal
pattern of uterine contractions
affecting the course of labour is
designated as disordered or
abnormal uterine action.”

6. Effective Uterine Contractions strats
at the cornua and gradually sweeps
downwards over the uterus.
In Primary Dysfunctional Labor,
Uterine Activity instead of being
governed by a single dominant
pacemaker, is shifted to less
efficient contractions due to
emergence of other pacemaker foci.
Oxytocin therapy may be effective in
restoring the global and effective uterine
contractions.

7. Primary Dysfunctional Labor, is
defined when the cervix dilates <
1cm/hr following a normal latent
phase of labor.
Commonest abnormality
Mostly corrected by,
Amniotomy or/and
Oxytocin Augmentation

8. Secondary Arrest, is defined when
the cervical dilatation stops or slows
after the active phase of labour has
started normally.

9. Uterine activity is measures by
noting...
Basal tone
Active (peak) pressure
Frequency

10. Assesment is usually done by...
Clinical Palpation (inaccurate)
Tocodynamometer with external
transducer
Using intrauterine pressure catheter
(accurate)
Normal baseline tonus is between 5
and 20 mm of Hg and peak pressure is
around 60 mm of Hg

11. INCEDENCE:-
25 % in Nulliparous Women
10 % in Multiparous Women

12. ETIOLOGY:-
Unknown
Prevalent in first birth specially with elderly
women
Prolonged Pregnancy
Overdistension of uterus ( twins & fibroids
Emotional factor ( anxiety, stress)
Constitutional labor ( obesity)
Contracted pelvis & malpresentation
Injudicious administration of sedatives,
analgesics & oxytocics
Premature attempt of VD & instrumental VD

13. TYPES:-

15. Abnormal Polarity
Ineffective Uterine Contraction

17. UTERINE INERTIA /
HYPOTONIC UTERINE
CONTRACTION

18. • Common but comparatively less serious
• May complecate at any stage of labour
• May be present from beginning of labour
or develop subsequently after a variable
period of effective contraction

19. Uterine Contractions...
The intensity is diminished
 Duration is shortened
 Good relaxation inbetween contractions
 Intervals are increased
General pattern of uterine contractions of
labor is maintained but intrauterine pressure
during contraction is below 25 mm of Hg.

20. Diagnosis...
 Patient feels less pain during contraction
 Hand placed over the uterus during uterine
contraction reveals less hardening of the
uterus
 Uterine wall is easily indentable at the
acme of a pain
 Uterus remains relaxed after contraction
 Fetal parts are well palpable
 Fetal heart rate remains normal

21. Internal Examination reveals...
 Poor dilation of the cervix
 Associated presence of contracted pelvis,
malposition, deflexed head or
malpresentation
 Membranes usually remains intact
Effects on mother and fetus...
 Maternal Exhaustion
 Fetal Distress , are unusual and appear
late.

22. Management...
 Case is reassessed to exclude CPD or
Malpresentation
Place of Cesarean Section...
 Presence of Contracted Pelvis
 Malpresentation
 Evidences of fetal or maternal distress

23. Vaginal Delivery...
Genral Measures:-
Keep up the morale of patient
 Manage maternal stress and emotion
 Avoid supine position
 Empty the bladder ( catheterization)
 Maintain hydration by infusion of
Ringer's solution
 Adequate pain relief

24. Vaginal Delivery...
 Active Measures:-
 Acceleration of uterine contraction by
low rupture of the membrane followed by
oxytocin drip
The drip rate is gradually increased until
effective contractions are set up
The drip is to be continued till one hour
after delivery

25. INCOORDINATE UTERINE
CONTRACTION

26. • Usually appears in active stage of
labour.
• The hypertonic state of the uterus
arises from any of the conditions such
as spastic lower uterine segment,
colicky uterus, asymmentrical uterine
contraction, contriction ring or
generalized tonic contraction of the
uterus and all thes states are
collectively called incoordinate uterine
contraction.

27. • Increased frequency and or duration of
uterine contractions cause rise in
baseline tone and thereby diminish
circulation in the placental intervillous
space.
• New pacemakers appear all over the
uterus.
• The myometrium contracts spasmodically
and irregularly.

28. • These contractions force neither dilates
the cervix nor pushes the fetus down.
• Uterine tonus is elevated.
• Pain is present before, during and after
contraction.
• This results in fetal hypoxia in labour.
• Placental abruption is often associated
with high baseline tone ( >25 mm Hg ).

29. • On cardiotocography (CTG) the FHR
shows reduced variability and late
decelerations.
• Uterine hyperstimulation due to oxytocics
are often associated with fetal tachycardia
due to fetal stress.
• Constriction ring, generalized tonic
uterine contraction and cervical dystocia
have got their own separate clinical entity
and as such will be discussed separately.

30. SPASTIC LOWER SEGMENT
Uterine Contractions...
 Fundal dominance is lacking and often
there is reversed polarity
 The pacemakers do not work in rhythm
 The lower segment contractions are
stronger
 Inadequate relaxation in between
contractions
 Basal tone is raised above the critical level
of 20 mm Hg

31. Diagnosis...
 The patient is in agony with unbearable
pain reffered to the back
There are evidences of dehydration and
ketoacidosis
Bladder is frequently distended and often
there is retention of urine, distension of
stomach and bowels are visible
There are premature attemps of bear down

32.  Abdominal palpation reveals:
a)Uterus is tender and gentle manipulation
excites hardening of the uterus with pain
b)Palpation of the fetal parts is difficult
 Internal examination may reveal :
a) Cervix with thick, edematous hangs
loosely like a curtain, not well appliedto the
presenting part
b) Inappropriate dilation of the cervix
c) Absence of mebranes
d) Meconium stained liquor amnii may ne
there

33. Effect on the fetus...
 Fetal distress appears early due to
placental insuffiency caused by inadequate
relaxation of the uterus

34. Management...
There is no place of oxytocin augmentation
with this abnormality
Cesarean section is done in majority of
cases
Prior correction of dehydration and
ketoacidosis must be achieved by rapid
infusion of Ringer's solution

35. CONSTRICTION RING
(Syn. Contraction ring/
Schroeder's ring)

36. It is one one form of incoordinate uterine
action where there is localized
myomatrial contraction forming a ring of
circular muscle fibres of the uterus
It is usually situated at the junction of
the upper and lower segment around a
constricted part of the fetus usually
around the neck in cephalic
presentation
It may appear in all the stages of labour
It is usually reversible and complete

37. Causes...
Injudicious administration of oxytocics
Premature rupture of the membranes
Premature attempt at instrumental delivery

38. Diagnosis...
Difficult
Revealed during cesarean section in the
first stage of labour, during forcep application
in second stageand during manual removal in
the third stage
The ring is not felt per abdomen
Maternal condition is not much affected but
the fetus is in jeopardy because of the
hypertonic state
Uterus never ruptures

39. Treatment...
Delivery is usually done by cesarean
section
The ring usually passes off ny deepening
the plane of anesthesia, otherwise the ring
may to be cut vertically to deliver the baby
The difficlties faced during forceps delivery
or during normal removal of placenta can be
overcome by using deep anesthesia that
relaxes the constriction ring

40. CERVICAL DYSTOCIA

41. Progressive cervical dilatation needs an
effective stretching force by the
preseting force by presenting part
Failure of cervical dilatation may be due
to :
a) Insufficient uterine contractions
b) Malpresentation, Malposition
(abnormal relationship between the
cervix and the presenting part)
Cervical dytocia may be primary or
secondary

42. Primary cervical dystocia...
Commonly observed during the...
i. First birth where the external os fails to
dilate
ii. Rigid cervix
iii. Insufficient uterine contractions
iv. others

43. Treatment...
In presence of associated complications
(malpresentation, malposition) cesarean
section is preferred
If the head is sufficiently low down with
only thin rim of cervix left behind, the rim may
be pushed up manually during contraction or
retraction is given by ventouse
In others where the cervix is very much
thinned out but only half dilated, Duhrssen's
incision at 2 and 10 O'clock positions
followed by forceps or ventouse extraction is
quite safe and effective

44. Secondary cervical dystocia...
This type of cervical dystocia results
usually due to excess scarring or rigidity of
the cervix from the effect of previous
operation or disease
Others are:
i. Post delivery
ii. Postoperative scarring
iii. Cervical cancer

45. GENERALIZED TONIC
CONTRACTION
(Syn. Uterinr Tetany)

46. In this condition, pronounced retraction
occurs involving whole of the uterus up to
the level of internal os
Thus, there is no physiological
differentiation of the active upper
segment and the passive lower segment
of the uterus
The whole uterus undergoes a sort of
tonic muscular spasm holding the fetus
inside (active retention of the fetus)
Usually there is no risk of rupture uterus
New pacemaker appear all over the uterus

47. Causes...
Cephalopelvic disproportion
Obstruction
Injudicious use of oxytocics

48. Clinical features...
The patient is in prolonged labour, having
severe and continuous pain
Abdominal examination reveals the uterus
to be somewhat smaller in size, tense and
tender
Fetal parts are neither well defined, nor is
the fetal heart sound audible
Vaginal examination reveals jammed head
with big caput, dry and adematous vagina

49. Treatment...
Correction of dehydration and ketoacidosis
by rapid infusion of Ringer's solution
Antibiotic
Adequate pain relief
Hypercontractility (tachysystole) induced by
oxytocics can be managed by tocolytics.
Oxytocin infusion should be stopped
esarean delivery is done in majority of the
cases specially when obstruction is
suspected

50. PRECIPITATE LABOUR

51. “ A labour is called precipitate when the
combined duration of the first and second
stage is less than two hours”
It is common in multiparae and be
repetitive
Rapid expulsion is due to the combined
effect of hyperactive uterine contractions
associated with diminished soft tissue
resistance
Labour is short as rate of cervical
dilatatiion is 5 cm/hour or more in
nulliparous women

52. Maternal risk...
1. Extensive laceration of the cervix, vagina
and perineum
2. PPH due to uterine hypotonia that
develops subsequent to unusual vigorous
contractions
3. Inversion
4. Uterine rupture
5. Infection
6. Amniotic fluid ambolism

53. Fetal risk...
1. Intracranial stress and hemorrhage
because of rapid expulsion without time
for moulding of the head
2. The baby may sustain serious injuries if
delivery occurs in standing position,
bleeding from the torn cord and direct hit
on the skull are real hazards

54. Treatment...
The patient having previous hystory of
precipitate labour should be hospitalized
prior to labour
During labour, the uterine contraction may
be suppressed by administering ether or
magnesium sulfate during contractions
Delivery of the head should be controlled
Episiotomy should be done liberally
Elective induction of labour by low rupture of
membranes and conduction of controlled
delivery is helpful
Oxytocin augmentation should be avoided

55. TONIC UTERINE
CONTRACTION AND
RETRACTION
(Syn. Bandal's ring / pathological
retraction ring)

56. This type of uterine contraction is
predominantly due to obstructed labour
Pathological anatomy of uterus...
There is gradual increase in intensity,
duration and frequency of uterine
contraction
The relaxation phase becomes less
and less, ultimately a state of tonic
contraction develops
Retraction, however, continues

57. The lower segment elongates and
becomes progressively thinner to
accomodate the fetus driven from the
upper segment
“ A circular groove encicling the uterus
is formed between the active upper
segment and the distended lower
segment, called pathological retraction
ring (Bandal's ring)”
Due to pronounced retraction, there is
fetal jeopardy or even death

58. In primigravidae, further retraction
ceases in response to obstruction and
labor comes to a stand still a state of
uterine exhaustion
Contractions may recommence after a
brief of rest with renewed vigour
But in multipare, retraction continues
with progressive circumferential
dilatation and thinning of the lower
segment

59. There is progressive rise of the
Bandal's ring, moving nearer and nearer
to the umbilicus and ultimately, the
lower segement ruptures

60. Clinical features...
1. Patient is in agony from continuous pain
and discomfort and becomes restlessness
2. Features of exhaustion and ketoacidosis
are evident
3. Abdominal palpation reveals:
•Upper segment is harder and tender
•Lower segment is distended and tender

61. Management...
Prevention:-
–Partographic management of labour, early
diagnosis of malpresentation, disproportion
and delivery by cesarean section can prevent
this condition completely

62. Treatment...
Rupture of the uterus is to be excluded
Internal version is contraindicated
Correction of dehydration and ketoacidosis
by infusion of Ringer's solution
Adequate pain relief
Parenteral antibiotic ( Cefriaxone 1 g IV )
Cesarean delivery is done in majority of the
cases
Rupture of the uterus must be excluded
before attempting destructive operation