Abnormal lie, Malpresentation and Malposition

Question 1

What are the risk factors for Abnormal lie, Malpresentation and Malposition

Answer 1

• Prematurity
• Multiple pregnancy
• Uterine abnormalities (e.g fibroids, partial septate uterus)
• Fetal abnormalities
• Placenta praevia
• Primiparity

Question 2

Define lie

Answer 2

Relationship between the long axis of the fetus and the mother, longitudinal, transverse or oblique

• Place your hands on either side of the uterus and gently apply pressure; one side will feel fuller and firmer this is the back, and fetal limbs may feel ‘knobbly’ on the opposite side

Question 3

Define presentation

Answer 3

The fetal part that first enters the maternal pelvis, cephalic vertex presentation is the most common

• Palpate the lower uterus (above the symphysis pubis) with the fingers of both hands; the head feels hard and round (cephalic) and the bottom feels soft and triangular (breech)

Question 4

Define position

Answer 4

position of the fetal head as it exits the birth canal, Usually occipito-anterior position (the fetal occiput facing anteriorly)

• Vaginal exam = landmarks of the fetal head, including the anterior and posterior fontanelles, indicate the position

Question 5

How are fetal lie and presentation usually identified?

Answer 5

Abdo exam

Question 6

How is fetal position identified?

Answer 6

Vaginal examination

Question 7

If abnormal fetal lie or malpresentation is suspected how should it be confirmed?

Answer 7

USS

Question 8

How should abnormal fetal lie be managed?

Answer 8

External cephalic version (ECV) = ideally between 36 and 38 weeks gestation

• complications = fetal distress, premature rupture of membranes, antepartum haemorrhage (APH) and placental abruption

Question 9

How should malpresentation be managed?

Answer 9

Breech = attempt ECV before labour, vaginal breech delivery or C-section

• Brow = a C-section is necessary
• Face
  o Chin anterior (mento-anterior) = normal labour is possible; however, it is likely to be prolonged and there is an increased risk of a C-section being required
  o Chin posterior (mento-posterior) = C-section
• Shoulder = C-section

Question 10

How should malposition be managed?

Answer 10

90% of malpositions spontaneously rotate to occipito-anterior as labour progresses

If the fetal head does not rotate, rotation and operative vaginal delivery can be attempted

Alternatively a C-section can be performed.