Fields proposed a scoring system in 1966 for evaluating a woman for labor induction. The index consists of 10 items, 5 of which are shared with the Bishop score.
Parameters:
(1) cervical dilation
(2) cervical effacement
(3) station of the presenting part
(4) consistency of cervix
(5) position of cervix
(6) estimated date of confinement
(7) estimated fetal weight
(8) uterine irritability after manual abdominal palpation
(9) vaginal secretions over past week
(10) patient's attitude towards induction
|
Parameter |
Finding |
Points |
|---|---|---|
|
dilation |
< 2 cm; closed, up to being able to admit 1 finger |
0 |
|
|
2 - 3 cm |
1 |
|
|
> 3 cm |
2 |
|
effacement |
< 80% |
0 |
|
|
80% (internal os "taken up") |
1 |
|
|
> 80% |
2 |
|
station of the presenting part |
-3 or -2 |
0 |
|
|
-1 or 0 |
1 |
|
|
+ 1 or +2 |
2 |
|
consistency of cervix |
firm |
0 |
|
|
somewhat softened and indentable (medium) |
1 |
|
|
soft and dilatable |
2 |
|
position of cervix |
posterior |
0 |
|
|
middle (45° to vaginal axis) |
1 |
|
|
anterior |
2 |
|
estimated date of confinement (EDC) |
3 weeks or more from term, or unknown |
0 |
|
|
more than 1 week but less than 3 weeks from term |
1 |
|
|
within 1 week from term |
2 |
|
estimated fetal weight |
< 2,500 grams |
0 |
|
|
unable to estimate |
1 |
|
|
> 2,500 grams |
2 |
|
uterine irritability after manual abdominal palpation |
flaccid after palpation |
0 |
|
|
some tension |
1 |
|
|
full, firm contraction |
2 |
|
vaginal secretion during past week |
no increase in discharge |
0 |
|
|
increase in mucous discharge |
1 |
|
|
increase, with blood tinge |
2 |
|
patient's attitude towards induction |
objects or fearful |
0 |
|
|
accepts (may hesitate) |
1 |
|
|
enthusiastic |
2 |
index =
= SUM(points for all 10 parameters)
Interpretation:
• minimum score: 0
• maximum score: 20
• Higher scores associated with shorter duration of labor and less need for assisted delivery or cesarean section.
• groups: 0-10, 11-15, 16-20
• Patents with scores of 16-20: induction is very successful in multiparous women with scores of 16-20; induction is very successful in nulliparous patients with scores of 18-20.
• Patients with scores 11-15: inconclusive but labor likely to be prolonged
• Patients with scores <= 10: not candidates for induction, but should be considered for cervical ripening.
Limitation:
• Hughey et al (1976) felt that the Fields index was valid but only infrequently applies to clinical situations where guidance is needed, since many patients fall in the 11-15 range and few reach the 16-20 range.
Purpose: To use the index proposed by Fields in 1966 to help evaluate a pregnant woman for labor induction.
Specialty: Obstetrics & Gynecology
Objective: other testing
ICD-10: O62,
