👶 Bishop Score Calculator
Calculate the Bishop Score to assess cervical readiness for labor induction. This obstetric tool evaluates five clinical parameters — cervical dilation, effacement, fetal station, consistency, and position — to predict the likelihood of successful vaginal delivery.
What Is the Bishop Score?
The Bishop Score is a clinical tool used in obstetrics to assess the readiness of the cervix for labor induction. It was introduced by Edward H. Bishop in 1964 and remains the most widely used method for predicting the likelihood of successful vaginal delivery following induction.
The score evaluates five clinical parameters, each assigned a value from 0 to 3, with a maximum total score of 13:
- Cervical Dilation (0–3): How open the cervix is, measured in centimeters.
- Cervical Effacement (0–3): How thin the cervix is, expressed as a percentage.
- Fetal Station (0–3): The position of the fetal head relative to the ischial spines.
- Cervical Consistency (0–2): How firm or soft the cervix feels on examination.
- Cervical Position (0–2): Whether the cervix is posterior, midposition, or anterior.
A higher score indicates a more favorable cervix — one that is more likely to respond to induction. A lower score suggests the cervix is unfavorable and may require cervical ripening before induction.
How to Interpret the Bishop Score
The total score is interpreted as follows:
≥ 8: Favorable cervix — high likelihood of successful induction. Oxytocin induction may be started directly, with success rates exceeding 90% in multiparous women.
6 – 7: Borderline — induction is possible, but cervical ripening may improve outcomes.
≤ 5: Unfavorable cervix — cervical ripening is recommended before induction. Risk of failed induction is significantly higher.
In Bishop's original 1964 study, a score of ≥ 9 indicated that the chance of vaginal delivery after induction was not statistically different from that observed with spontaneous labor.
Modified and Simplified Bishop Scores
Over the decades, several modifications have been proposed:
- Modified Bishop Score: Replaces effacement with cervical length (measured by ultrasound), increases the weight of cervical dilation, and adds additional modifiers. Used in some institutions for improved predictive accuracy.
- Simplified Bishop Score (Laughon, 2011): Uses only three components — dilation, station, and effacement — with a range of 0–9. Studies show it achieves similar predictive ability to the original score.
Clinical Applications
- Predicting induction success: Higher scores correlate with shorter induction-to-delivery intervals and higher vaginal delivery rates.
- Guiding cervical ripening: Low scores (≤ 5) prompt consideration of prostaglandins, balloon catheters, or other ripening agents before oxytocin induction.
- Counseling patients: The score helps clinicians discuss the likelihood of successful induction and set expectations.
- Standardizing assessment: Provides a consistent, reproducible framework for evaluating cervical readiness across providers.
Why Use This Calculator?
- Instant scoring: Click the options for each of the five parameters and get the total score in real time.
- Clinical interpretation: Immediate feedback on whether the cervix is favorable, borderline, or unfavorable.
- Reference panel: View the full scoring table, interpretation thresholds, and key evidence.
- Free & private: No registration, no data storage — all calculations are done in your browser.
❓ Bishop Score Calculator FAQ
What is a Bishop Score?
The Bishop Score is a clinical scoring system used to assess cervical readiness for labor induction. It evaluates five parameters — dilation, effacement, station, consistency, and position — with a total score ranging from 0 to 13.
What is a favorable Bishop Score?
A score of ≥ 8 is generally considered favorable for induction, indicating a high likelihood of successful vaginal delivery. A score of ≤ 5 is considered unfavorable.
What does a Bishop Score of 6 or 7 mean?
A score of 6–7 is considered borderline. Induction may be successful, but cervical ripening may improve the chances of a smooth induction.
What are the five components of the Bishop Score?
The five components are: cervical dilation (0–3), effacement (0–3), fetal station (0–3), cervical consistency (0–2), and cervical position (0–2).
How is the Bishop Score calculated?
The score is the sum of the individual scores for each of the five parameters. Each parameter is assigned a score based on the clinical finding, and the total ranges from 0 to 13.
What is the difference between the Bishop Score and the Modified Bishop Score?
The Modified Bishop Score replaces effacement with cervical length (measured by ultrasound), increases the weighting of cervical dilation, and adds additional modifiers. The Simplified Bishop Score uses only three components (dilation, station, effacement) with a range of 0–9.
Who invented the Bishop Score?
The Bishop Score was introduced by Edward H. Bishop in 1964 in the journal Obstetrics & Gynecology.
Does a high Bishop Score mean labor will start on its own?
A high Bishop Score (≥ 8) suggests that the cervix is favorable and spontaneous labor may begin soon. However, it does not guarantee that labor will start without induction — it predicts the likelihood of successful induction if performed.
How accurate is the Bishop Score?
The Bishop Score is a widely validated tool with moderate predictive accuracy. Its accuracy varies based on parity (higher in multiparous women), gestational age, and clinical context. It is best used alongside other clinical assessments.
Is this calculator free?
Yes, this calculator is completely free to use. No registration or personal data storage is required.