Bishop Score Calculator
Estimate your bishop score with our free gynecology & pregnancy calculator. See reference ranges, risk factors, and next-step guidance.
Calculator
Adjust values & calculate0 = closed, 1 = 1-2cm, 2 = 3-4cm, 3 = 5+cm
0 = 0-30%, 1 = 40-50%, 2 = 60-70%, 3 = 80+%
0 = -3, 1 = -2, 2 = -1/0, 3 = +1/+2
0 = firm, 1 = medium, 2 = soft
0 = posterior, 1 = mid, 2 = anterior
Component Breakdown
Formula
Each cervical characteristic is scored independently. Dilation measures cervical opening (0-5+cm), effacement measures cervical thinning (0-80+%), station measures fetal descent (-3 to +2), consistency evaluates firmness (firm to soft), and position notes cervical direction (posterior to anterior). Total range is 0-13.
Last reviewed: January 2026
Worked Examples
Example 1: Favorable Cervix Assessment
Example 2: Unfavorable Cervix Assessment
Background & Theory
The Bishop Score Calculator applies the following established principles and formulas. Health and medicine calculators are grounded in validated physiological measurement methods established through decades of clinical research. Body Mass Index, or BMI, is calculated by dividing weight in kilograms by height in meters squared (kg/m²), a formula originating from Adolphe Quetelet's 19th-century statistical work and later codified by the WHO into standard classifications: underweight below 18.5, normal weight 18.5 to 24.9, overweight 25 to 29.9, and obese at 30 and above. Basal Metabolic Rate quantifies the minimum energy required to sustain life at rest. The Mifflin-St Jeor equation, published in 1990 and widely regarded as the most accurate for most adults, calculates BMR as (10 × weight in kg) + (6.25 × height in cm) − (5 × age) ± sex adjustment. The older Harris-Benedict equations, revised in 1984 by Roza and Shizgal, remain in common use. Total Daily Energy Expenditure is derived by multiplying BMR by a physical activity factor ranging from 1.2 for sedentary individuals to 1.9 for extremely active ones, following the methodology validated by doubly labeled water studies. Body fat percentage can be estimated without laboratory equipment using the U.S. Navy circumference method, which uses neck, waist, and hip measurements, or via BMI-derived equations adjusted for age and sex. The Jackson-Pollock skinfold method offers higher precision with calipers. Blood pressure classification, according to the American College of Cardiology and the 2017 ACC/AHA guidelines, defines normal as below 120/80 mmHg, elevated as 120 to 129 systolic, and hypertension stage 1 as 130 to 139 systolic or 80 to 89 diastolic. Target heart rate zones for aerobic exercise are derived from maximum heart rate estimates, most commonly using the formula 220 minus age in years, with moderate-intensity training typically defined as 50 to 70 percent of maximum heart rate and vigorous intensity at 70 to 85 percent, consistent with CDC and American Heart Association guidelines. These thresholds guide safe and effective cardiovascular conditioning.
History
The history behind the Bishop Score Calculator traces back through the following developments. The history of health measurement stretches back to ancient Greece, where Hippocrates around 400 BCE laid the foundation for observational medicine by systematically recording patient symptoms, diet, and environment. His humoral theory, though scientifically superseded, established the principle that the body operates as an interconnected system subject to measurable imbalance. The transformation toward modern medicine accelerated in the 19th century. Louis Pasteur and Robert Koch developed germ theory in the 1860s and 1870s, identifying microorganisms as disease agents and enabling targeted interventions. Florence Nightingale, working during the Crimean War in the 1850s, introduced statistical analysis to nursing practice, demonstrating through data visualization that sanitation reduced mortality. Her work is foundational to evidence-based health measurement. The discovery of vitamins in the early 20th century, beginning with Casimir Funk's coinage of the term in 1912 and culminating in the isolation of vitamins A through K, created the field of nutritional science and gave rise to dietary reference intake frameworks. The World Health Organization, founded in 1948, subsequently established global standards for health metrics, disease classification through the International Classification of Diseases, and recommended daily allowances. The BMI as a clinical screening tool gained traction in the 1970s through Ancel Keys' large-scale epidemiological work, which validated Quetelet's index as a population-level obesity indicator. Through the 1980s and 1990s, the Framingham Heart Study produced landmark data linking cholesterol, blood pressure, and lifestyle factors to cardiovascular disease risk, directly shaping the numeric thresholds still used in health calculators. The evidence-based medicine movement, formalized by Gordon Guyatt and colleagues at McMaster University in the early 1990s, demanded that all health recommendations derive from systematically graded clinical evidence. The digital health era beginning in the 2000s brought these formulas to consumer devices, wearable sensors, and smartphone applications, expanding access to health self-monitoring on a global scale and enabling population-level data collection that continues to refine clinical reference ranges.
Frequently Asked Questions
Formula
Bishop Score = Dilation (0-3) + Effacement (0-3) + Station (0-3) + Consistency (0-2) + Position (0-2)
Each cervical characteristic is scored independently. Dilation measures cervical opening (0-5+cm), effacement measures cervical thinning (0-80+%), station measures fetal descent (-3 to +2), consistency evaluates firmness (firm to soft), and position notes cervical direction (posterior to anterior). Total range is 0-13.
Worked Examples
Example 1: Favorable Cervix Assessment
Problem: A 39-week pregnant woman presents with dilation 3cm (score 2), effacement 70% (score 2), station -1 (score 2), soft consistency (score 2), and anterior position (score 2). What is her Bishop Score?
Solution: Dilation: 3cm = 2 points\nEffacement: 70% = 2 points\nStation: -1 = 2 points\nConsistency: soft = 2 points\nPosition: anterior = 2 points\nTotal Bishop Score = 2 + 2 + 2 + 2 + 2 = 10
Result: Bishop Score: 10/13 (Favorable) - High likelihood of successful induction, oxytocin induction appropriate
Example 2: Unfavorable Cervix Assessment
Problem: A 41-week pregnant woman presents with dilation closed (score 0), effacement 20% (score 0), station -3 (score 0), firm consistency (score 0), and posterior position (score 0). What is her Bishop Score?
Solution: Dilation: closed = 0 points\nEffacement: 20% = 0 points\nStation: -3 = 0 points\nConsistency: firm = 0 points\nPosition: posterior = 0 points\nTotal Bishop Score = 0 + 0 + 0 + 0 + 0 = 0
Result: Bishop Score: 0/13 (Unfavorable) - Cervical ripening recommended before induction attempt
Frequently Asked Questions
What is the Bishop Score and why is it used in obstetrics?
The Bishop Score is a standardized clinical assessment tool developed by Dr. Edward Bishop in 1964 to evaluate cervical readiness for labor induction. It assigns numerical values to five cervical characteristics: dilation, effacement, station, consistency, and position. The total score ranges from 0 to 13, with higher scores indicating greater likelihood of successful induction. Healthcare providers use this scoring system to determine whether a patient needs cervical ripening before induction or if the cervix is already favorable enough for direct oxytocin administration. The Bishop Score remains one of the most widely used pre-induction assessment tools in modern obstetric practice worldwide.
What Bishop Score is considered favorable for labor induction?
A Bishop Score of 8 or higher is generally considered favorable for labor induction, meaning the cervix is ready and induction is likely to succeed. Scores between 5 and 7 are considered moderately favorable, where induction can proceed but may require longer time or additional interventions. Scores of 4 or below indicate an unfavorable cervix that would benefit from cervical ripening agents before attempting induction. Research shows that patients with a Bishop Score above 8 have induction success rates comparable to spontaneous labor outcomes. The threshold may vary slightly between institutions, with some using 6 as their cutoff for favorable status.
How is cervical dilation scored in the Bishop Score system?
Cervical dilation is scored on a scale of 0 to 3 points in the Bishop Score system. A closed cervix receives 0 points, dilation of 1-2 centimeters receives 1 point, dilation of 3-4 centimeters receives 2 points, and dilation of 5 centimeters or more receives the maximum 3 points. Dilation refers to how wide the cervical opening has become, measured during a digital vaginal examination. This component is one of the most predictive individual elements of the Bishop Score because significant dilation indicates the cervix has already begun the process of preparing for delivery. Progressive dilation over time is also an important clinical indicator of labor progress.
What does cervical effacement mean and how does it affect the score?
Cervical effacement refers to the thinning and shortening of the cervix, measured as a percentage from 0% (full length, about 3-4cm) to 100% (paper thin). In the Bishop Score, effacement of 0-30% scores 0 points, 40-50% scores 1 point, 60-70% scores 2 points, and 80% or more scores 3 points. Effacement is crucial because it indicates how much the cervix has softened and prepared for dilation. A fully effaced cervix is much more likely to dilate rapidly during induction compared to a thick, uneffaced cervix. Many clinicians consider effacement to be equally important as dilation when assessing cervical readiness for labor.
What is fetal station and how is it measured for the Bishop Score?
Fetal station describes the position of the presenting part of the baby (usually the head) relative to the ischial spines of the maternal pelvis. Station is measured from -3 (floating above the pelvis) to +3 (crowning at the vaginal opening), with 0 being at the level of the ischial spines. In the Bishop Score, a station of -3 receives 0 points, -2 receives 1 point, -1 or 0 receives 2 points, and +1 or +2 receives 3 points. A lower station (baby further descended into the pelvis) contributes to a higher Bishop Score and suggests that labor induction is more likely to succeed because the baby is already engaged.
How do cervical consistency and position contribute to the Bishop Score?
Cervical consistency and position each contribute up to 2 points to the Bishop Score. Consistency evaluates how soft the cervix feels: firm (like the tip of your nose) scores 0, medium scores 1, and soft (like the inside of your cheek) scores 2 points. A softer cervix is more favorable for induction because it dilates more easily. Cervical position refers to the direction the cervix faces in the vagina: posterior (facing backward) scores 0, mid-position scores 1, and anterior (facing forward) scores 2 points. An anterior cervix is easier to access and typically indicates the cervix is preparing for labor naturally.
References
Reviewed by Rahul Singh, Health & Wellness Specialist · Editorial policy