B28. Breech presentation, transverse lie

Breech presentation

Breech presentation is a form of abnormal presentation when the foetus presents with the buttocks or feet instead of the head. This presentation increases the risk for complications.

We distinguish three different types of breech presentation:

  • Frank breech – both hips are flexed, both knees are extended (most common)
  • Incomplete breech – One or both hips are not flexed
    • Single footling breech – hip of one leg is flexed, knee of the other is extended
    • Double footling breech – both knees and legs are extended
  • Complete breech – both hips and both knees are flexed (least common)

Breech is problematic because:

  • The body of the foetus may pass through the cervix before it’s fully dilated, but the head can’t pass, causing the shoulders or head to become trapped. This can cause asphyxia.
  • There is more space for the umbilical cord to prolapse.

Breech is common early in pregnancy, but most early pregnancy breech foetuses spontaneously rotate to cephalic presentation approaching term. It accounts for 3 – 4% of term foetuses.

Etiology

  • Prematurity
  • History of breech presentation
  • Polyhydramnios, oligohydramnios

Clinical features

The mother may feel the foetus kicking in the lower abdomen. She may also feel discomfort in the subcostal area due to the foetal head.

Diagnosis and evaluation

Leopold’s manoeuvres may suggest breech position, but the diagnosis is made with ultrasound. If not diagnosed antepartum, it will be apparent during delivery.

Treatment

External cephalic version may be attempted. This is a technique which attempts to rotate the foetus to cephalic presentation by manipulating the mother’s abdomen. It’s not often successful (40%), but it’s relatively safe.

If unsuccessful, the choice of whether to attempt vaginal labour or to go with C-section must be made. Vaginal delivery is attempted if:

  • Estimated foetal weight 2500 – 3500 g
  • Breech is frank or complete (not incomplete)
  • Size of the pelvis is normal

During vaginal delivery of breech foetuses, it’s important to apply as little traction as possible. The mother’s efforts alone should account for the majority of the expulsion. If the mother’s expulsive efforts are insufficient, specific manoeuvres (Burns-Marshall, Bracht) may be used. Application of suprapubic pressure helps delivery of the head.

Complications

  • Umbilical cord prolapse
  • Perinatal asphyxia
  • Developmental dysplasia of the hip
  • Increased perinatal mortality

Transverse lie

Transverse lie is an abnormal form of foetal lie where the foetus lies transversally in the uterine cavity, rather than longitudinally. Like breech, most foetuses with transverse lie early in the pregnancy convert to a longitudinal lie (cephalic or breech) by term.

Etiology

  • Placenta praevia
  • Abnormal uterine anatomy
  • Polyhydramnios

Clinical features

If the maternal abdomen is unusually wide, transverse lie should be suspected.

Diagnosis and evaluation

Leopold’s manoeuvres may suggest transverse lie, but the diagnosis is made with ultrasound.

Treatment

Transverse lie does not allow for vaginal delivery. External cephalic version may be attempted. If unsuccessful, the foetus must be delivered by C-section.