Mailath-Pokorny et al developed models for predicting risk of preterm birth. One model predicts the risk of delivery before 32 weeks of gestation. The authors are from the Medical University of Vienna and Karl Landsteiner Institute for General Gynecology and Experimental Gynecologic Oncology.
Patient selection: week of gestation 21 to 32 weeks
Parameters:
(1) preterm premature rupture of the membranes (PPROM)
(2) vaginal bleeding
(3) cervical length in mm
(4) week of gestation
(5) serum C-reactive protein (CRP) in mg/dL
(6) fibronectin
Parameter |
Finding |
Points |
preterm PROM |
no |
0 |
|
yes |
100 |
vaginal bleeding |
no |
0 |
|
yes |
70 |
fibronectin |
negative |
0 |
|
positve |
21 |
points for cervical length =
= MAX(0,85.2 - (1.5491 * (mm)))
points for week of gestation =
= 152.727 - (4.7727 * (weeks))
CRP |
Points |
< 0.02 |
0 |
0.02 to 0.12 |
(-2940 * ((CRP)^2)) + (666.8 * (CRP)) - 10.51 |
0.12 to 0.5 |
(-13.13 * ((CRP)^2)) + (46.3 * (CRP)) + 23.09 |
0.5 to 4 |
(-2.171 * ((CRP)^2)) + (17.3 * (CRP)) + 38.15 |
4 to 32 |
(-0.03273 * ((CRP)^2)) + (2.121 * (CRP)) + 65.53 |
> 32 |
100 |
total score =
= SUM(points for all 6 parameters)
Interpretation:
• The higher the score the greater the risk of delivery prior to 32 weeks of gestation..
Points |
Probability of Delivery within 48 Hours |
< 39.3 |
< 1% |
39.3 to 229.5 |
(0.002279 * ((points)^2)) - (0.1061 * (points)) - 0.945 |
229.5 to 297.3 |
(-0.000968 * ((points)^2)) + (0.6427 * (points)) - 6.11 |
> 297.3 |
> 99% |
Specialty: Obstetrics & Gynecology
ICD-10: ,