Macones et al developed a nomogram for predicting the probability of cesarean section in a primipara. The authors are from Washington University in St. Louis and Saint Louis University.
Patient: primipara
Outcome: probability of cesarean section
Parameters:
(1) age in years (from 14 to 40)
(2) fetal-pelvic index (FPI, from -70 to +30)
(3) race
(4) labor method
points for age =
= (1.065 * (age)) - 14.92
points for fetal-pelvic index =
= (fetal-pelvic index) + 70
Parameter |
Finding |
Points |
race |
Black |
2 |
|
non-Black |
0 |
labor method |
spontaneous |
0 |
|
augmented or induced |
12.2 |
total score =
= SUM(points for all 4 parameters)
Interpretation:
• minimum score: 0
• maximum score: 142
• The higher the score the greater the probability of cesarean section.
Total Score |
Probability in Percent |
< 55 |
< 1% |
55 to 81 |
(0.03698 * ((points)^2)) - (4.298 * (points)) + 125.5 |
81 to 98 |
(2.96 * (points)) - 220.4 |
98 to 108 |
(-0.09428 * ((points)^2)) + (21.44 * (points)) - 1126 |
> 108 |
> 90% |
Specialty: Obstetrics & Gynecology
ICD-10: ,