Along with the possible associations and investigations in pregnancy, there are a few factors that caregivers may try to use, to help 'predict' shoulder dystocia when the woman is in labour. Again, these are not very accurate, and are only indications that could possibly guide the caregiver when considering possible shoulder dystocia. These can include:
Slow progress in the 2nd stage
Caput and moulding and fetal distress
Assisted delivery
'Positive turtle sign'
Slow progress in the 2nd stage. If the baby is actually
macrosomic, then their passage down the birth canal can be slower than expected. It is for this reason that a longer than average 2nd stage, or pushing phase, can possibly indicate a higher chance of shoulder dystocia. Weak contractions, epidurals and the baby's head being deflexed (not tucked in with their chin on their chest), can also contribute to slow progress at this time.
If the baby is believed to be more than 4,500 grams, and the woman is working hard to move her baby down, but the baby is moving very slow, for the amount of effort being made (with good contractions), then the caregiver may suggest a Caesarean operation. Some caregivers place time limits on the pushing phase, being more than 2 hours for first time mothers, and about 1 hour for women having their subsequent baby
Caput, moulding and fetal distress. As the baby makes their way down the vagina, it is normal for their head to mould to the shape of the woman's pelvis, and develop a small amount of
caput (or swelling). Moulding occurs because the five separate skull bone plates of the baby, are able to move towards each other and slightly overlap, protecting the baby's brain. This natural process makes the baby's head become longer and thinner, (returning to a normal shape within a first few days after the birth). If the baby is unusually large, the moulding can be more pronounced.