This document defines and discusses transverse lie, an abnormal fetal position where the long axis of the fetus is perpendicular to that of the mother. Key points include:
- Transverse lie results in a shoulder presentation and has a 1 in 200 incidence rate. It is more common in preterm/macerated fetuses and multiparous women.
- Diagnosis involves abdominal/pelvic examination and ultrasound to confirm the lie beyond 36 weeks.
- Untreated transverse lie poses risks like cord prolapse and obstructed labor. Modern management includes external cephalic version or cesarean section for delivery.
- Unstable lie with constantly changing presentation poses similar risks and is managed with version attempts and close monitoring
2. Definition
A transverse lie occurs when the fetal long
axis lies perpendicular to that of the
maternal long axis and classically results in
a shoulder presentation.
3. Position
The position is determined by the direction of
the back, which is a denominator.
1. Dorsoanterior-most common (60%).
2. Dorsoposterior-increased risk of arm
prolapse
3. Dorsosuperior
4. Dorsoinferior
4.
5. Incidence
Incidence- 1 in 200 births
More common in premature and macerated
fetuses
5 times more common in multiparae than
primigravidae
40% of twin pregnancy cases
8. Palpation
The fundal height is smaller than her
gestational age
Breech or head is not palpable on fundal
grip
On lateral grip, breech on one side of
midline and head on the other side
Palpation over the pelvic brim will reveal an
‘empty’ pelvic.
9. Auscultation
FHS – heard easily below umbilicus in
dorsoanterior position
In dorsoposterior position, FHS may be
heard at high level or indistinct
10. Vaginal Examination
During pregnancy, presenting part is too
high that it cannot be identified properly but
one can feel some soft parts.
During labour, elongated bag of the
membranes can be felt if it does not rupture
prematurely.
11. The shoulder is identified by palpating the
following parts
acromion process
the scapula
the clavicle
the axilla
12. Ultrasound Scan
Transverse lie is confirmed by ultrasound
scan beyond 36 weeks
Spontaneous version – before 36 weeks
13. Risk of transverse lie
The woman presenting at term with a
transverse lie is at potential risk of
cord prolapse following spontaneous rupture
of the membranes
Prolapse of the hand, shoulder or foot
14. Clinical course of labour
No mechanism of labour for transverse lie and
an average size baby fails to pass through an
average size pelvis.
If the lie remains uncorrected and the labour is
left uncared for, the following sequence of
events may occur.
Unfavourable events
Favourable events
15. UNFAVOURABLE EVENTS
Common
The hand of the corresponding shoulder may
be prolapsed with or without a loop of cord
With increasing uterine contraction, the
shoulder becomes wedged and impacted into
the pelvic and the prolapsed arm becomes
swollen and cyanosed.
16. Complications are impacted shoulder
obstructed labour rupture of uterus with
clinical evidence of
Dehydration
Ketoacidosis
Shock
sepsis
19. Prognosis
In a well supervised pregnancy and labour,
the maternal and the fetal outlook is not
much unfavourable with the increased use of
cesearean section.
In uncared pregnancy and labour, the
maternal risk is increased due to obstructed
labour. Fetal risk is increased due to cord
prolapsed.
20. Management of transverse lie
ECV should be done in all cases beyond 36 weeks.
Contraindications to ECV
Fetal abnormality
Placenta praevia
Oligohydramnios or polyhydramnios
Previous scar on the uterus
Multiple gestation
PE or hypertension
21. If version fails or contraindicated:
Admission at 37th wk because risk of early
rupture of the membranes and cord prolapse
is very much there. Elective cesarean section
is the preferred mode of delivery.
Vaginal delivery may be allowed in dead
or small size fetus under supervision.
22. Patient seen in labour
Early labour:
External cephalic version: should be tried in
all cases if no contraindication.
If version fails or contraindicated, cesarean
section is the preferred method of delivery.
23. Late labour
Delivered by cesarean section whether the
baby is alive or dead
In modern practice , internal version is not
recommended except in the case of second twin.
24. Unstable lie
This is the condition where the presentation of
the fetus is constantly changed even beyond
36th week of pregnancy when it should have
been stabilized.
25. Causes
1) Grand multipara with the lack of uterine
tone and pendulous abdomen- the most
common cause
2) Polyhydramnios
3) Contracted pelvis
4) Placenta previa
5) Pelvic tumor
26. Management of unstable lie
Antenatal management
At each AN visit , the presentation and the
lie are to be checked.
External cephalic version: to be done if no
contraindication.
27. Time of admission
At 37th week
Premature or early rupture of the membrane
with cord prolapse is a real danger with
oblique lie.
29. Mode of delivery
(1) Cesarean section
The normal plan would be to deliver by
cesarean section if the presentation is not
cephalic in early labour or of spontaneous
rupture of membrane occurs.
30. (2) Vaginal delivery
ECV is done ( if not contraindicated) after 37
weeks. Oxytocin infusion is started to initiate
effective uterine contractions. This is followed
by low rupture of the membranes. Labour is
monitored for successful vaginal delivery.