Bishop Score Calculator — Cervical Ripening for Labor Induction
The Bishop Score is a clinical scoring system used to assess cervical ripening before labor induction. It helps predict the likelihood of successful induction by evaluating five components of the cervix.
About
The Bishop Score, originally described by Dr. Edward Bishop in 1964, is a pre-induction cervical scoring system that evaluates five components: cervical dilation, effacement, station of the presenting fetal part, cervical consistency, and cervical position. Each component is assigned a score of 0-3 (with consistency and position scored 0-2), yielding a total score from 0 to 13. Higher scores indicate a more favorable cervix for induction. The score is interpreted based on parity: a score ≥8 is favorable for nulliparous women, while ≥6 is favorable for multiparous women.
Formula
Bishop Score = Dilation + Effacement + Station + Consistency + Position (0-13)
The Bishop Score is calculated by summing the points assigned to each of five cervical components. Dilation: 0 cm = 0, 1-2 cm = 1, 3-4 cm = 2, 5-6 cm = 3. Effacement: 0-30% = 0, 40-50% = 1, 60-70% = 2, 80%+ = 3. Station: -3 = 0, -2 to -1 = 1, 0 = 2, +1 to +2 = 3. Consistency: Firm = 0, Medium = 1, Soft = 2. Position: Posterior = 0, Mid = 1, Anterior = 2. Total score ranges from 0 to 13. In nulliparous women, a score ≥8 is considered favorable, while in multiparous women, a score ≥6 is considered favorable. Scores below the threshold suggest an unfavorable cervix requiring ripening agents prior to induction.
Score Interpretation
The Bishop Score is the most widely used pre-induction cervical assessment tool in obstetrics, developed by Dr. Edward Bishop in 1964. A favorable Bishop Score (≥8 for nulliparous, ≥6 for multiparous) is associated with a higher likelihood of successful vaginal delivery and lower rates of cesarean section following labor induction. The score guides clinical decision-making regarding the need for cervical ripening agents (such as prostaglandins), the timing of induction, and patient counseling about expected outcomes. Studies have shown that the Bishop Score has moderate predictive value for successful induction, and it remains the standard of care despite the development of alternative methods such as transvaginal ultrasound cervical length measurement and the simplified Bishop Score.
Unfavorable Cervix — High Risk of Failed Induction — 0–5
Bishop Score 0-5. Unfavorable cervix regardless of parity. High likelihood of failed induction without cervical ripening.
Management: Administer cervical ripening agents (prostaglandins). Reassess Bishop Score after ripening before proceeding with oxytocin. Higher risk of cesarean delivery.
Favorable Cervix (Multiparous) / Borderline (Nulliparous) — 6–7
Bishop Score 6-7. Favorable for multiparous women, but unfavorable for nulliparous women. Decision depends on parity.
Management: For nulliparous women: consider cervical ripening. For multiparous women: proceed with induction if other factors are favorable.
Favorable Cervix — Good Induction Candidate — 8–13
Bishop Score 8-13. Favorable cervix for induction in both nulliparous and multiparous women. High likelihood of successful induction.
Management: Proceed with induction of labor as planned. Lower risk of failed induction and cesarean delivery. Monitor labor progression per standard protocols.
Reference Ranges
| Population | Normal Range | Notes |
|---|---|---|
| Pregnant women undergoing pre-induction cervical assessment | 0-13 points (Favorable: ≥8 nulliparous, ≥6 multiparous) | Score ≥8 for nulliparous and ≥6 for multiparous women indicates favorable cervix. Lower scores suggest need for cervical ripening. |
Dr. Mahmoud El-Sayed
Dr. Mahmoud is an endocrinology consultant with expertise in metabolic and endocrine disorders in pregnancy.
View medical review board & editorial policy →Example Calculation
A 28-year-old nulliparous woman at 41 weeks gestation is being assessed for labor induction. Vaginal examination reveals: cervical dilation 3 cm (2 points), effacement 60% (2 points), fetal station -1 (1 point), cervical consistency medium (1 point), cervical position anterior (2 points). Total Bishop Score = 2 + 2 + 1 + 1 + 2 = 8. Since the threshold for nulliparous is ≥8, the cervix is favorable. Proceed with induction of labor as planned. Good prognosis for successful vaginal delivery.
Related Conditions
Related Medications
Common Mistakes
Using the same threshold for both nulliparous and multiparous women
The threshold for a favorable cervix differs by parity: ≥8 for nulliparous and ≥6 for multiparous women. Always account for parity when interpreting the Bishop Score.
Relying solely on the Bishop Score without considering other clinical factors
The Bishop Score is a useful tool but should be interpreted alongside other factors including gestational age, maternal comorbidities, fetal status, and obstetric history. A low Bishop Score does not absolutely contraindicate induction but suggests the need for ripening.