A focused bedside aid for translating five vaginal-examination findings into the 13-point Bishop score and a cautious, guideline-aware interpretation.
01
Purpose and limits
The Bishop score estimates cervical readiness and helps clinicians plan cervical ripening or an induction method. It does not diagnose the indication for delivery, guarantee vaginal birth, or independently decide between induction and expectant management.
Decision rule
First decide whether delivery is indicated from the maternal–fetal assessment. Then use the Bishop score to help select the induction approach.
02
Pre-requisites
Obtain informed written consent.
Review the maternal history and clinical profile.
Confirm the indication and exclude contraindications.
Establish reliable gestational age, fetal presentation and estimated fetal weight.
Record maternal pulse, blood pressure, temperature, respiratory rate and abdominal examination findings.
Evaluate the baseline fetal heart-rate pattern by auscultation or electronic monitoring.
Assess the maternal pelvis and possible cephalopelvic or fetopelvic disproportion, including fetal macrosomia.
Assess cervical status with the Modified Bishop score to estimate success and guide the induction method.
Document the indication, gestational age and Modified Bishop score when the induction decision is made.
03
How points are assigned
A consented vaginal examination assesses five findings. Choose one band in each row and add the points once; the maximum is 13.
01Cervical dilation
Estimate the average diameter of the cervical opening in centimetres during a consented digital examination.
Closed
0 points
1–2 cm
1 point
3–4 cm
2 points
>4 cm
3 points
02Cervical length / effacement
Assess cervical shortening as remaining length or as percentage effaced, then select one corresponding band.
>2 cm (~0–30%)
0 points
1–2 cm (~40–50%)
1 point
0.5–1 cm (~60–70%)
2 points
<0.5 cm (~≥80%)
3 points
03Cervical consistency
Describe how the cervix feels: firm, medium or soft. Softening reflects cervical remodelling.
Firm
0 points
Medium
1 point
Soft
2 points
04Cervical position
Record the cervix relative to the presenting part as posterior, central or anterior.
Posterior
0 points
Central
1 point
Anterior
2 points
05Fetal station
Record the presenting part relative to the ischial spines: negative above, zero at the spines and positive below.
−3
0 points
−2
1 point
−1 or 0
2 points
+1 or +2
3 points
The Kenyan national table records cervical length, while the traditional NIH description records percentage effacement. This calculator presents both clinical descriptions in one row so the finding is scored once. The configured 3-point dilation band is >4 cm; some traditional tables display this as ≥5 cm when charting whole centimetres.
Kenyan modified-score note
Clinician-applied adjustments
The base assessment totals 13 points. Kenya’s national guideline labels 6–13 favourable and 1–5 unfavourable.
+1 point
Pre-eclampsia
+1 point
Each previous vaginal delivery
−1 point
Postdate pregnancy
−1 point
Nulliparity
−1 point
PPROM
These modifiers are shown for clinical reference and are not added automatically. Apply them only when following the Kenyan Modified Bishop protocol used by your facility.
04
Precautions built into interpretation
Confirm before induction
Document the indication, reliable gestational age, consent, presentation, fetal status, membrane status, parity, uterine scar and suitability for vaginal birth.
Do not use the score alone
A low score does not justify delaying an indicated delivery, and a high score is not by itself an indication to induce.
Respect examination contraindications
Avoid digital cervical examination when contraindicated, including suspected placenta praevia or unexplained bleeding pending obstetric assessment.
Match method to risk
Mechanical or pharmacological ripening, amniotomy and oxytocin require facility protocols, monitoring and emergency caesarean capability.
Interpret thresholds transparently
Kenyan guidance groups 6–13 as favourable. The NIH traditional-score review notes that many studies use >8; neither threshold guarantees induction success.
Use current local protocol
Medicine, dosing, monitoring and management of a scarred uterus are deliberately not prescribed by this calculator.
05
Clinical references
National Guidelines on Quality Obstetrics and Perinatal Care (2022)
Elegant Tools