Malposition and Malpresentation Flashcards
What are the three ways to describe how the baby is passing through the birth canal?
LIE, PRESENTATION and POSITION
What are some examples of types of lie?
Cephalic (head down)
Breech (feet or bum first)
Transverse (baby is horizontal)
Oblique (baby on diagonal)
What is presentation and what are some examples?
Which part of the fetus is at the pelvic brim
Face, Brow, Breech
What is position and what are some examples?
The way in which the presenting part is orientated relative to the maternal pelvis
IDEAL: Occipito-transverse at the pelvic brim rotating to occipitoanterior at the pelvic floor
How common is face presentation? What are its associations and complications?
1 in 500 births
Associated with anencephaly (missing part of brain)
Usually only recognised at the onset of labour
Described with relation to chin ‘mento-‘
Cesarean section usually required
This delivery is possible because the face is a similar diameter to the occiput but it is associated with more trauma (bruising and oedema)
How common is brow presentation? How concerning is it? How is it managed?
This is when the supra-orbital ridges or the bridge of the nose present
It is the least favourite of the malpresentations
If it persists then a CS will be required
How common is breech presentation at 20w, 32w and term?
What is breech presentation associated with (contributing factors)?
40% at 20w are breech, 25% at 32w and 3-4% at term
- Chance of turning spontaneously after 38w is 4%
Associated with multiple pregnancy, bicornuate uterus, fibroids, poly and oligo-hydramnios
What is the name of the normal presenting diameter and how wide is it?
Suboccipitobregmatic diameter = 9.5cm
What are the management options for malposition?
BREECH can offer external cephalic version (ECV) - palpation of the abdomen to try and encourage the baby to turn
When is ECV offered?
36w in nullips and 37w in multips
How likely is ECV to be successful?
30% success rate in nullips and 50% success in multips
What makes the chances of ECV succeeding more likely?
If the baby’s head is flexed rather than extended (frank)
What should you do if the turn is only partially successful on ECV?
If only partially successful (e.g. get baby into transverse lie) then you should put the baby back into breech position as this is safer than transverse
Can you deliver breech babies vaginally?
How should it be managed?
YES but should only be attempted by an experienced obstetrician
You should try and discourage the mother from pushing
The greatest risks are of the baby’s head extending and getting caught on the pelvic brim OR the cervix constricting around the neck of the baby
