The Bishop Score is used to rate how ready your cervix is for induction or how likely labor is to start on its own. The Bishop Score adds up points from five measurements: dilation, effacement, the baby’s station, consistency of your cervix, and the position of your cervix. The table below can help you calculate your score:
Dr. Edward Bishop developed his scoring system in the 1960s. The original use of the Bishop Score was to determine how likely a woman is to go into labor; these days it is used to determine if the cervix is favorable for an induction. A score of 8 or higher indicates that an induction would likely result in a vaginal delivery, while a score of 10 indicates that labor is likely to start on its own within a matter of days and an induction is likely unnecessary. A score of 6 or below indicates that the cervix is not favorable for an induction.
Breaking Down the Score:
Dilation refers to how open the cervix is in centimeters. This measurement is taken across the cervical opening from one side to the other. For reference, a cheerio is equivalent to 1 cm dilation, a banana slice is equivalent to 3 cm dilation, and a kiwi slice is equivalent to 5 cm dilation. Just for fun, a bagel is equal to 10 cm dilated! Come back in two weeks for more information on dilation.
Effacement is the shortening and thinning of the cervix; this is measured as a percentage. Zero percent effaced means your cervix is still long and thick. If you are 100% effaced this means your cervix is completely effaced or paper thin.
The baby’s station refers to where your baby’s head is in relation to the ischial spines, the bony projections of your pelvis. A zero station means your baby’s head is even with the ischial spines. Negative numbers mean your baby’s head is above the ischial spines, while positive numbers mean your baby’s head is below the ischial spines.
Consistency refers to the texture of your cervix during an examination. A firm cervix is hard and rubbery (similar to the tip of your nose), a soft cervix may feel like puckered lips, and a medium cervix is somewhere in between.
Position refers to where the cervix is in relation to the pelvis. A posterior cervix is towards the back of the pelvis and is usually harder to feel, and an anterior cervix is lower and towards the front of the pelvis. The cervix is much easier to feel when it becomes anterior.
Knowing your Bishop Score allows you to be more informed about your body. Anytime you have a cervical check you should ask your doctor what your Bishop Score is. Better yet, ask what each measurement is and calculate it yourself. This allows you to know where your body stands if your doctor begins discussing a possible induction with you.
Next week I will be blogging on the letter C… C is for Cervical Checks.