Malpresentation

Question 1

What is the difference between malpresentation and malposition?

Answer 1

• Malpresentation - longitudinal lie but vertex is not presenting part
• Malposition - vertex presentation but not occipito-anterior position

Question 2

What is a breech presentation? How often does it occur?

Answer 2

• Where the foetal buttocks or lower extremities present
• 3% at term (15% at 30 weeks)

Question 3

What are predisposing factors to a breech-presenting baby?

Answer 3

• Foetal: prem, multiplets, congenital malformations
• Liquor: oligo/polyhydramnios
• Uterine: cavity distortions (fibroids, cancer)
• Placenta: praevia
• Pelvis: contractures or birth canal obstructions

Question 4

What is the difference between a frank/complete/footling breech baby?

Answer 4

• Frank 65% - extended legs
• Complete 25% - fully flexed
• Footlng 10% - one or both thighs extended

Question 5

What are the problems associated with breech birth?

Answer 5

• 4x increase in perinatal mortality
  
  • Asphyxia and birth trauma
• Associations: premature labour, PPROM, foetal abnormalities, placenta praevia and abruption

Question 6

Why is there an increased risk to a baby of asphyxia/birth trauma with a breech presentation?

Answer 6

• Cord prolapse
• Entrapment of the foetal head (cervix, disproportion)
• Traumatic injury (CNS, nerve/muscle injury)
• Arm hyperextension

Question 7

What are the management options for a mother with a breech-presenting baby?

Answer 7

• External cephalic version
• Elective caesarean section
• Trial of vaginal delivery

Question 8

How is external cephalic version performed?

Answer 8

• 60-70% success
  
  • Done at >=36 weeks in case of (very rare) complications and need for delivery
  • Initial CTG, tocolytic (terbutaline) to relax uterus, attempt to perform forward somersault, CTG afterwards and anti-D if Rh-

Question 9

What are the contraindications to performing external cephalic version?

Answer 9

• T3 bleeding, uterine abnormalities, ruptured membranes, oligohydramnios, need for C-section or vaginal delivery required

Question 10

What are the indications for an elective caesarean section delivery?

Answer 10

• Low or high foetal weight
• Preterm
• Hyperextended foetal head
• Placenta praevia
• Concerns about foetal wellbeing
• Footling or complete breech

Question 11

In the setting of breech presentation, when might a trial of vaginal delivery be allowed?

Answer 11

• Frank or complete breech
• Foetal weight 2.5-3.5 kg
• Gestation > 36 weeks
• Flexed foetal head
• Adequate pelvis
• No indications for C-section
• Experienced team

Question 12

What is the most common kind of face malpresentation? When might you decide to move to a caesarean section?

Answer 12

• Mentoanterior
• If mentotransverse/mentroposterior do not rotate to mentoanterior. Most MA deliver vaginally well

Question 13

What are the characteristics on vaginal examination of a baby presenting face-first?

Answer 13

• Mouth located (no sphicnter tone!)
• Mouth forms triangle with malar prominences

Question 14

What are the characteristics on vaginal examination of a baby presenting brow-first?

Answer 14

• Anterior fontanelle
• Orbital ridges
• Eyes

Move to CS if this presentation persists (risk of hyperextension)

Question 15

How is a diagnosis of foetal shoulder malpresentation made?

Answer 15

• Palpation of the head not in the pelvis
• Palpation on vaginal exam of other foetal parts presenting