The prediction of shoulder dystocia is important because is could prepare the labor & delivery team for a dangerous situation and also it may help in the counseling of pregnant women.

Shoulder dystocia is a dangerous situation where the baby's shoulder gets stuck in the mother's pelvis, usually behind her pubic bone. It's rare and happens in about 0.6%-1.4 % of all vaginal deliveries. When shoulder dystocia is diagnosed, the L&D team should make sure there is not too much traction on the baby's head and institute some maneuvers to prevent injury.

Dangers of shoulder dystocia include injury to the baby such as nerve injury (brachial plexus injury, Erb's palsy, Klumpke's palsy).

Many shoulder dystocias occur unexpectedly, but many more also have some risk factors such as big babies, slow labors, diabetes, abnormal sugar tests, and operative deliveries such as forceps or vacuum

I came across an older publication that I found very interesting


It was published in 2007 in the Journal of Perinatology by Dr.Belfort and his team and it's called: "Prediction of Shoulder Dystocia Using Multivariate Analysis".

They found that certain risks factors could help in opredicting shoulder dystocia. The thre major factors were:

  • elevated baby's birthweight
  • abnormal carbohydrate intolerance (GCT >140 mg/dl)
  • increased height of fundus
  • delivery mode (forceps or vacuum)

Other risks factors included maternal age >=35 yrs, more than 5 prior births, diabates itself,  station at forceps <2.

They came up with a mathematic score to predict shoulder dystocia:

score = 0.0028 (birthweight in grams – 2387) + 2.92 (carbohydrate intolerance; yes=1, no=0) + 1.31 (delivery mode; operative=1, spontaneous=0).

Other risk factors for shoulder dystocia include:

  • Diabetes
  • Macrosomia
  • Previous shoulder dystocia
  • Precipitous labor
  • Abnormal labor
  • Older mothers
  •  Obeisty
  • Elevated abdominal circumference
  • Maternal weight gain
  • Fetal sex