Abnormal uterine action

OBG

1. ABNORMAL UTERINE
ACTION
NAZNEEN VAHORA
CLINICAL INSTRUCTOR,
MTIN,CHARUSAT

2. BRIEF REVIEW OF NORMAL
UTERINE CONTRACTIONS
POLARITY OF UTERUS : When upper segment
contracts, lower segment relaxes.
PACEMAKERS : Two pacemakers situated at
each cornua of uterus generating the
contraction in co-ordinated manner.
PATTERN OF CONTRACTIONS : uterine
contraction starts at cornua, propagates
towards lower uterine segment with decrease
in the duration and intensity of contraction as it
moves away from pacemaker.

3. PARAMETERS OF UTERINE
CONTRACTION
•BASAL TONE: 5-20mmHg.
•PEAK PRESSURE: around 60 mm Hg
pressure
•FREQUENCY OF CONTRACTION
Adequate uterine contractions are 1 in 3
minutes lasting for 45 seconds.

4. DEFINITION
•Any deviation from normal pattern of
uterine contractions affecting the normal
course of labour is designated as
abnormal uterine contraction.
Over all labour abnormalities occur in
•25%nulliparous
•10%multiparous

5. EXCESSIVE UTERINE
CONTRACTION
POLYSYSTOLE :contractions more than once
every 2 minutes.
HYPERSTIMULATION : the above in response
to oxytocin
TETANIC UTERINE CONTRACTION : single
contraction lasting for more than 3 minutes .
HYPERTONIC UTERINE CONTRACTION :
Elevated baseline pressure above 20mm Hg.

6. ETIOLOGY
Cause is obscure but following conditions are
often associated:
Elderly primigravidae
Prolonged pregnancy
Over distended uterus- twins, fibroid
Contracted pelvis
Malpresentation
Obesity
Emotional factor: anxiety and stress
Injudicious administration of sedative,
analgesics, oxytotics

7. CLASSIFICATION

9. UTERINE INERTIA
May appear from the beginning of labour or
may develop subsequently after variable
period of effective contractions.
FEATURES:
•Intensity of contractions- decreases
•Duration –shortens
•Interval – increases
•Good relaxation
•General pattern maintained

10. DIAGNOSIS
Patient feels less pain during contraction
Per abdomen:
-less hardening of uterus
-easily indentable uterine wall
-Fetal parts well palpable
-Fetal heart rate normal
Per vaginal examination
-poor cervical dilatation
-associated contracted pelvis,
malpresentation, malposition, deflexed head

11. MANAGEMENT
GENERAL MEASURES:
Keep up the morale
Avoid supine position
Empty the bladder
Maintain hydration
ACTIVE MEASURES:
Low rupture of membranes followed by
oxytocin drip in escalating doses until
effective uterine contractions set up.

12. ROLE OF CAESAREN SECTION:
-contracted pelvis
-malpresentation
-fetal or maternal distress

13. PRECIPITATE LABOUR
Combined duration of 1
st
and 2
nd
stage of
labour is < 2 hours.
-common in multipara
-Due to combined effect of hyperactive
uterine contractions and diminished soft
tissue resistance

14. RISK
MATERNAL
•Extensive laceration
of cervix, vagina,
perineum.
•PPH due to
subsequent uterine
hypotonia
•Inversion
•Uterine rupture
•Infection
•Amniotic fluid
embolism
FETUS
•Intracranial stress
and hemorrhage( as
no time for moulding)
•Direct hit on the skull
•Bleeding from Torn
cord

15. TREATMENT
•Patient with prior history should be
hospitalized prior to labour.
•Elective induction of labour by low rupture
of membranes.
•Oxytocin augmentation to be avoided.
•During labour the contractions may be
suppressed with ether or magnesium
sulphate.
•Liberal episiotomy.
•Controlled delivery.

16. TONIC UTERINE CONTRACTION
AND RETRACTION
PATHOLOGICAL ANATOMY OF UTERUS:
Contraction increases in intensity ,duration and
frequency with decreased relaxation in between

Retraction continues
Progressive thinning & elongation of lower uterine
segment

Development of circular groove b/n upper and lower
segment-called BANDL’S RING.


/

18. In primigravidae further retraction ceases in
response to obstruction and labour comes
to a stand still-a state of exhaustion.
In multiparae retraction continues with
progressive dilatation and thinning of lower
uterine segment
Bandl’s ring moves towards the
umblicus
Rupture of lower uterine segment
Fetal jeopardy and death

19. Clinical features
•Patient is anxious looking
•Features of exhaustion and ketoacidosis
•Upper uterine segment is tender and hard
•Lower uterine segment distended and
tender
•Groove is seen between the two.

20. TREATMENT
•Correction of dehydration & ketoacidosis
•Adequate pain relief
•Parenteral antibiotics
EXCLUDE RUPTURE OF UTERUS
Caesarean delivery in majority of cases

21. ABNORMAL UTERINE ACTION

22. FEATURES
•Hypertonic uterine state
•Appear in active stage of labour
•New pacemakers appear all over the
uterus
•Irregular and spasmodic contraction of
uterus
•Increased frequency& duration of
contraction with decreased relaxation in
between.
•Rise in the basal tone

24. Clinical features
Patient in agony with unbearable pain
dehydration and ketoacidosis
Bladder is distended with often retention of
uterine
PER ABDOMEN:
Uterine tenderness
Increased uterine contraction with poor
relaxation in between
Palpation of fetal parts is difficult
fetal distress in the form of fetal tachycardia

25. PER VAGINAL EXAMINATION:
•Cervix –poor dilatation
•Poor descent
•Meconium stained liquor may be present

26. TREATMENT
•Correction of dehydration

•Adequate pain relief
•Empty the bladder
•Parenteral antibiotics

27. SPASTIC LOWER SEGMENT
•Fundal dominance is lacking
•Reverse polarity
•Lower segment contractions are stronger
•Inadequate relaxation in b/n the
contractions
•Premature bearing down
•Cervix loose, oedematus, not well applied
to the presenting part

28. MANAGEMENT:
Most of the patients need to be terminated by
caesarean section

29. CONSTRICTION RING
Also called Schroeder’s ring.
May appear in all stages of labour.
Localized myometrial contraction forms a ring
of circular muscle fibers of the uterus
Situated at the junction of upper and lower
segment
Usually around constricted part of the fetus.

31. CAUSE:
• Injudicious administration of oxytocin
•Premature rupture of membranes
•Premature attempt of instrumental delivery

32. FEATURES
•Maternal condition not affected
•Fetal distress may occur
•Ring is not palpable during per abdomen
•Felt in
ofirst stage during –caesarean section
oSecond stage –forceps application
oThird stage –manual removal of placenta

33. Delivery is usually by caesarean section
Ring usually passes of by deepening plane of
anaesthesia.
In case of difficulties ring is cut vertically to
deliver the baby.

34. CONSTRICTION RING
Localised
incoordinate uterine
contraction
Undue irritability of
uterus
Usually at the junction
of upper and lower
uterine segment
Upper segment
contracts and retracts
with relaxation in
between
Lower uterine
segment thick and
loose
RETRACTION RING
•End result of tonic uterine
contraction and retraction
•Following obstructed
labour
•Always at the junction of
upper and lower uterine
segment
•Tonically contracted
upper uterine segment
•Lower uterine segment
thinned out

35. CONSTRICTION RING
•MATERNAL
condition Always
unaffected unless
labour is prolonged
•Ring is not felt on
per abdomen
•Round ligament not
felt
On per vaginal
examination ring
can be felt usually
above head
RETRACTION RING
•Maternal exhaustion
and sepsis appear
early
•Ring is felt as a
groove
Round ligament taut
and tender
Can not be felt on per
vaginal examination

36. CERVICAL DYSTOCIA
Failure of progressive cervical dilatation.
TYPES:
a)Primary
b)Secondary

37. TYPES OF CERVICAL
DYSTOCIA
PRIMARY
I.First birth when
ext os fails to
dilate
II.Rigid cervix
III.Insufficient
uterine
contraction
IV.Malpresentation
and malposition
SECONDARY
I.Excessive
scarring or rigidity
of cervix from
previous
operation or
disease
II.Post delivery
III.Cervical cancer

38. MANAGEMENT:
If only thin rim of cervix left behind- it is
pushed up manually during contraction
If cervix is thinned out but only half dilated –
Duhrssens’s incision is given at 2’oclock
and 10 o’clock position followed by
forceps or ventouse extraction

39. GENERALISED TONIC
CONTRACTION
Also called uterine tetany
No physiological differentiation between
active upper segment and passive lower
segment.
Pronounced retraction occurs involving whole
of the uterus up to the level of internal os.
Whole uterus undergoes a tonic muscular
spasm holding the fetus inside

41. CAUSE:
-Cephalopelvic disproportion
-obstruction
-injudicious use of oxytocics

42. FEATURES
PER ABDOMINAL EXAMINATION
•Uterus is smaller in size, tense, tender
•Fetal parts are not palpable
•Fetal heart sounds not audible
PER VAGINAL EXAMINATION
•Dry and oedematus vagina
•Jammed head with a big caput

43. TREATMENT
•Tocolytic agents for e.g terbutalin 0.25mg
S.C.
•Caesarean delivery is done in majority of
cases.