Bishop Score Calculator
Bishop cervix score 0 to 13 for induction readiness with bands.
What it does
Induction works when the cervix is ready and stalls when it is not. The Bishop score grades readiness from five exam findings, each scored small, for a total 0 to 13. Edward Bishop published it in 1964 and labor wards still quote it daily.
The tool above sums the five parts at once. Enter dilation, effacement, station, consistency, and position. It returns the total, the favorable to unfavorable band, and the induction direction. Defaults of 2, 2, 2, 1, 1 open solved at 8, favorable.
The split between 3 point and 2 point parts is the logic to memorize. Dilation, effacement, and station each run 0 to 3 while consistency and position cap at 2, which is why the ceiling is 13 rather than 15. Station is the odd one out: it grades the baby, not the cervix.
Eight is the famous line. At 8 or more, induction succeeds about 95 percent of the time, often with oxytocin and broken waters alone. At 5 or less, half fail without ripening first, so prostaglandins or a Foley balloon lead. Six and 7 sit between, decided case by case.
Use the table to fix bands in memory, then score the exam. Only a clinician's fingers can judge these parts; the page exists so the conversation about ripening versus oxytocin runs on numbers.
How to use
- Record dilation from the exam.
- Record effacement percent.
- Record station vs the spines.
- Judge consistency and position.
- Read the total first, then the band.
- Plan ripening or oxytocin with the team.
Formula
- Dilation
- How open: closed to 5 cm plus.
- Effacement
- How thin: 0 to 30% up to 80% plus.
- Station
- Head height vs ischial spines: -3 to +2.
- Consistency
- Firm, medium, or soft.
- Position
- Posterior, mid, or anterior.
Dilation: closed 0, 1 to 2 cm 1, 3 to 4 cm 2, 5 cm or more 3. Effacement: 0 to 30% 0, 40 to 50% 1, 60 to 70% 2, 80% or more 3. Station: -3 is 0, -2 is 1, -1 or 0 is 2, +1 or +2 is 3. Consistency: firm 0, medium 1, soft 2. Position: posterior 0, mid 1, anterior 2. Totals 8 and up favorable, 6 to 7 intermediate, 5 and down unfavorable.
Worked example
Example: total 8, favorable
Dilation 3 to 4, effacement 60 to 70, station -1, medium, mid position. Score it.
- Dilation 3 to 4 cm is 2 points.
- Effacement 60 to 70% is 2 points.
- Station minus 1 is 2 points.
- Consistency medium is 1 point.
- Position mid is 1 point.
- Total 8: favorable, induction succeeds about 95% of the time.
Reference table
| Total | Band | Direction |
|---|---|---|
| 0 to 5 | Unfavorable | Ripen first (worked zero: 0) |
| 6 to 7 | Intermediate | Clinician decides |
| 8 to 13 (worked: 8) | Favorable | Proceed to induction |
| 13 | Fully ready | Proceed (max case) |
Limits
- Clinician exam findings only.
- Term singleton assumptions behind bands.
- Does not fit twins, breech, prior cesarean.
- One snapshot; cervices evolve.
Common mistakes
- Scoring effacement as dilation.
- Forgetting consistency caps at 2.
- Inducing on a 3 without ripening.
- Treating 6 to 7 as clearly favorable.
- Ignoring membranes and history.
Try it yourself
Quick checks. Answers sit tucked under each question.
Completely closed firm posterior exam?
All zeros total 0: Unfavorable, ripen first.
Fully ready exam, all maximum?
3 + 3 + 3 + 2 + 2 = 13: Favorable, proceed.
Dilation 2, effacement 1, station 1, medium, posterior?
2 + 1 + 1 + 1 + 0 = 5: Unfavorable, ripen first.
Questions
What are the 5 parts?
Dilation, effacement, station, consistency, position. The first three score 0 to 3, the last two 0 to 2, total 0 to 13.
What score is good?
8 or more is favorable, 6 to 7 intermediate, 5 or less unfavorable. In multiparous term patients 8 predicts smooth induction.
What if the score is low?
Ripen first with prostaglandin, balloon, or both. Starting oxytocin on a closed firm cervix fails about half the time.
Can I score myself?
Only a clinician on vaginal exam can judge them. Patients can learn the parts to join the induction conversation.
What is the modified Bishop?
It swaps percentage effacement for measured cervical length in cm, totaling 12. Same idea, less examiner guesswork.
Does it fit every pregnancy?
No. Twins, breech, prior cesarean, and ruptured membranes change the decision beyond any score.
Sources
- ACOG: cervical ripening in pregnancy, Bishop scoring
- StatPearls: Bishop score components and bands (NCBI)