Bishop Score Calculator
The Bishop score is a standardized obstetric assessment of cervical readiness (favorability) for labor induction. Published by Dr. Edward Bishop in 1964, it evaluates five characteristics of the cervix during pelvic examination: dilation, effacement, station of the presenting part, consistency, and position. Each criterion is scored and the sum gives the Bishop score (0-13). A score of 8 or above predicts a cervix favorable for induction and is associated with high rates of successful vaginal delivery. Scores below 6 typically indicate the need for cervical ripening before oxytocin induction. Select the clinical findings below to calculate the Bishop score.
Bishop score formula
Bishop Score = Dilation + Effacement + Station + Consistency + Position
Range: 0 (completely unfavorable) to 13 (maximally favorable)
Each criterion is scored independently and summed. The score reflects cervical ripeness for labor. A score of 8 or above is the conventional threshold for a favorable cervix where oxytocin induction is likely to succeed without prior ripening.
Clinical interpretation
- Score 0-5: Unfavorable cervix. Cervical ripening recommended before induction.
- Score 6-7: Intermediate. Consider ripening or proceed based on clinical context.
- Score 8-13: Favorable cervix. Induction likely to succeed. Oxytocin can be started directly.
Frequently asked questions
What is the Bishop score?
The Bishop score, introduced by Edward Bishop in 1964, is a pre-labor cervical assessment system that predicts the likelihood of successful labor induction. It evaluates five cervical features: dilation, effacement, station, consistency, and position, each scored on a scale of 0-2 or 0-3, giving a total of 0-13.
What Bishop score indicates a favorable cervix?
A Bishop score of 8 or above is generally considered favorable for labor induction, predicting a high likelihood of successful vaginal delivery. A score below 6 is considered unfavorable, and cervical ripening agents (prostaglandins, balloon catheter) are often used before oxytocin induction.
How is each Bishop component scored?
Dilation (cm): 0=closed, 1=1-2 cm, 2=3-4 cm, 3=5+ cm. Effacement (%): 0=0-30%, 1=40-50%, 2=60-70%, 3=80%+. Station: 0=-3, 1=-2, 2=-1/0, 3=+1/+2. Consistency: 0=firm, 1=medium, 2=soft. Position: 0=posterior, 1=mid, 2=anterior.
What cervical ripening methods are used for low Bishop scores?
For unfavorable cervices (Bishop below 6), common ripening methods include prostaglandin E2 (dinoprostone), misoprostol (PGE1), transcervical Foley balloon catheter, and osmotic dilators. The choice depends on gestational age, contraindications, and institutional protocols.
Does Bishop score predict spontaneous labor?
The Bishop score was originally developed to predict spontaneous delivery in multiparous patients at term. A high score predicts that the cervix is ready for labor. However, it is less predictive in nulliparous patients and those with post-dates pregnancies, where additional assessments may be needed.
Official sources
- American College of Obstetricians and Gynecologists (ACOG): Practice Bulletin: Induction of Labor.
- NIH National Library of Medicine: PubMed (Bishop EH 1964 original paper).
Reviewed by the CalculatorHub team, edited by James Graham, 15 June 2026. See our methodology.