The total score is achieved by assessing the following five components on vaginal examination:The Bishop score grades patients who would be most likely to achieve a successful induction. The duration of labor is inversely correlated with the Bishop score; a score that exceeds 8 describes the patient most likely to achieve a successful vaginal birth. Bishop scores of less than 6 usually require that a cervical ripening method be used before other methods.
- Cervical dilation
- Cervical effacement
- Cervical consistency
- Cervical position
- Fetal station
They can be remembered with the mnemonic: Call PEDS For Parturition = Cervical Position, Effacement, Dilation, Softness; Fetal Station.
Each components is given a score of 0-2 or 0-3. The highest possible score is 13. Bishop score
Parameter\Score 0 1 2 3 Description Position
Posterior Intermediate Anterior - The position of the cervix varies between individual women. As the anatomical location of the vagina is actually downward facing, anterior and posterior locations relatively describe the upper and lower borders of the vagina. The anterior position is better aligned with the uterus, and therefore there is an increased likelihood of spontaneous delivery. Consistency Firm Intermediate Soft - In primigravid
women the cervix is typically tougher and resistant to stretching, much like a balloon that has not been previously inflated. Furthermore, in young women the cervix is more resilient than in older women. With subsequent vaginal deliveries the cervix becomes less rigid and allows for easier dilation at term. Effacement
0-30% 31-50% 51-80% >80% Effacement is a measure of stretch already present in the cervix. It is analogous to stretching a rubber band; as the rubber band is stretched further, it becomes thinner. This is affected by individual variation and previous surgery such as loop excision
for cervical dysplasia
or cancer. Dilation
0 cm 1-2 cm 3-4 cm >5 cm Dilation is a measure of the diameter of the stretched cervix. It complements effacement, and is usually the most important indicator of progression through the first stage of labour. Fetal station -3 -2 -1, 0 +1, +2 Fetal station describes the position in of the foetus' head in relation to the distance from the ischial spines
, which can be palpated deep inside the posterior vagina (approximately 8-10cm) as a bony protrusion. Negative numbers indicate that the head is further inside, above the ischial spines.