Bishop Score Calculator
Professional assessment tool for cervical readiness and labor induction success.
- Dilation: 0 points
- Effacement: 0 points
- Station: 0 points
- Consistency: 0 points
- Position: 0 points
Probability of successful vaginal delivery: High
Visual Score Distribution
Chart showing point contribution for each category (Max 3 per bar).
What is a Bishop Score Calculator?
The Bishop Score Calculator is a clinical assessment tool used by obstetricians and midwives to determine how "ready" or "ripe" the cervix is for labor. Originally developed by Dr. Edward Bishop in 1964, this scoring system predicts the likelihood that an induction of labor will result in a successful vaginal delivery.
Healthcare providers use the Bishop Score Calculator during late pregnancy, typically when considering a scheduled induction for medical or elective reasons. A high score suggests that the body is naturally preparing for labor, making induction more likely to succeed. Conversely, a low score may indicate that cervical assessment is necessary to decide if ripening agents are needed first.
Common misconceptions include the idea that a low score means labor will never start naturally. In reality, the Bishop Score Calculator only assesses the current state of the cervix and does not predict when spontaneous labor will occur.
Bishop Score Formula and Mathematical Explanation
The Bishop Score Calculator operates on a cumulative point system across five distinct physical parameters. Each parameter is assigned a value from 0 to 2 or 0 to 3.
| Variable | Meaning | Points 0 | Points 1 | Points 2 | Points 3 |
|---|---|---|---|---|---|
| Dilation | Opening of cervix (cm) | Closed | 1-2 cm | 3-4 cm | 5+ cm |
| Effacement | Thinning of cervix (%) | 0-30% | 40-50% | 60-70% | 80%+ |
| Station | Fetal head position | -3 | -2 | -1, 0 | +1, +2 |
| Consistency | Texture of cervix | Firm | Medium | Soft | – |
| Position | Direction of cervix | Posterior | Mid-position | Anterior | – |
The formula is simply: Total Bishop Score = D + E + S + C + P
Practical Examples (Real-World Use Cases)
Example 1: Favorable for Induction
A patient at 40 weeks gestation presents with a cervix dilated to 3 cm (2 pts), 80% effaced (3 pts), at -1 station (2 pts), soft consistency (2 pts), and anterior position (2 pts). Using the Bishop Score Calculator, the total is 11. This indicates a very high probability of successful induction.
Example 2: Unfavorable for Induction
A patient at 39 weeks with medical indications for induction has a closed cervix (0 pts), 30% effacement (0 pts), -3 station (0 pts), firm consistency (0 pts), and posterior position (0 pts). The Bishop Score Calculator result is 0. In this case, doctors would likely use prostaglandin gels or a Foley bulb for cervical ripening before attempting pitocin induction.
How to Use This Bishop Score Calculator
- Enter the Cervical Dilation found during your pelvic exam.
- Select the Effacement percentage (how thin the cervix is).
- Input the Fetal Station (how low the baby's head is).
- Describe the Consistency and Position of the cervix.
- The Bishop Score Calculator will automatically update the total and interpretation.
- Use the "Copy Results" button to save the data for your medical records or to discuss with your doula.
Key Factors That Affect Bishop Score Results
- Parity: Women who have given birth previously (multiparity) usually have higher scores and more successful inductions than first-time mothers (nulliparity).
- Gestational Age: The score naturally increases as the pregnancy progresses toward 42 weeks.
- Maternal BMI: High BMI can sometimes make the cervical assessment more challenging.
- Fetal Weight: A very large baby may not descend into the pelvis as easily, affecting the "Station" component of the Bishop Score Calculator.
- Provider Experience: Cervical exams are subjective; different providers might score a cervix slightly differently.
- Membrane Status: If the water has already broken, the score's predictive value for induction timing may change.
Frequently Asked Questions (FAQ)
A score of 8 or higher is generally considered "favorable" for a successful vaginal delivery following induction. Scores of 6 or 7 are in the gray area, while 5 or less suggest a "ripe" cervix is needed.
No. It only predicts the success of an active induction of labor. It does not calculate the date of spontaneous labor.
If the Bishop Score Calculator shows a low result (under 6), your provider may recommend cervical ripening agents like Cervidil, Cytotec, or mechanical methods like a balloon catheter.
The modified version often replaces effacement (in %) with cervical length (in cm) using ultrasound, as it can be more objective.
The parameters require a sterile vaginal exam performed by a trained professional. It is not recommended to perform this on yourself.
While a high score on the Bishop Score Calculator significantly increases the odds, it does not guarantee a vaginal birth, as other complications can arise during labor.
A lower station (e.g., +1) means the baby is deeper in the pelvis, which puts pressure on the cervix to dilate, leading to a higher score.
An anterior (forward-facing) cervix is more aligned with the birth canal and is a sign that the body is preparing for the labor process.
Related Tools and Internal Resources
- Due Date Calculator – Estimate your baby's arrival date based on LMP or conception.
- Pregnancy Weight Gain Calculator – Track healthy growth during your trimesters.
- Ovulation Calculator – Plan for conception by tracking your fertile window.
- Labor Contraction Timer – Monitor your contractions once labor starts spontaneously.
- Apgar Score Calculator – Assessment of newborn health immediately after birth.
- C-Section Risk Assessment – Understand the factors that might lead to surgical delivery.