Burke et al developed a nomogram for predicting the chances of a cesarean delivery of a term nulliparous woman. The authors are from the Perinatal Ireland Research Consortium.
Patient selection: term nulliparous woman in labor
Outcome: cesarean section
Parameters:
(1) age in years, from 20 to 40 years
(2) body mass index (BMI), from 25 to 45 kg per square meter
(3) height in centimeters, from 145 to 165
(4) fetal head circumference, from 300 to 360 mm
(5) fetal abdominal circumference, from 300 to 360 mm
points for age =
= (0.219 * (age)) - 4.38
points for BMI =
= (0.352 * (BMI)) - 8.81
points for height =
= (-0.5 * (height)) + 82.53
points for fetal head circumference =
= (0.107 * (head circumference)) - 32.21
points for fetal abdominal circumference =
= (0.076 * (abdominal circumference)) - 22.79
total score =
= SUM(points for all 5 parameters)
Interpretation:
• minimum score: 0
• maximum score: 33
• The higher the score the greater the chances of a cesarean section being performed.
|
Points
|
Percent with Cesarean Section
|
|
< 5.5
|
< 10%
|
|
5.5 to 18.4
|
(0.1152 * ((points)^2)) + (0.3621 * (points)) + 4.47
|
|
18.4 to 31.2
|
(-0.1275 * ((points)^2)) + (9.399 * (points)) - 79.84
|
|
> 31.2
|
> 90%
|
