WTF is BISHOP Score and Why Does it Matter?

Hello loves! As you near the end of your pregnancy, you might start hearing the word "induction" floating around at appointments with your provider. It all sounds great, you're over being pregnant, it's freaking hot, you can't sleep - so why not right?

Approximately 1 in 4 pregnant people will be induced, any in most of those cases, it isn't medically necessary. Some are, but most are not. As much as we don't want to hear it, the safest thing to do is to wait for your baby to come when they are ready.

More than half of medical inductions will end in emergency cesarean. With induction rates this high, understanding what medical induction is, when you it is safe to get it and all it entails can help demystify the induction process and reduce fear, which can make your whole birth experience more satisfying. Medical inductions can be successful, but you need to know your stuff!

One of the best ways you can gauge your chances of a successful medical induction is by knowing your Bishop score. So, WTF is a Bishop score?

Basically, the Bishop Score is a calculation of 5 components used to evaluate the cervix for readiness for induction. The Bishop score is rated 0-13. This can be helpful to determine the likelihood of a successful vaginal delivery from labor induction. Your Bishop score is mostly determined through a cervical check from your doctor or midwife.

A Bishop score of 8 or greater is considered to be most favorable for induction, or the chance of a vaginal delivery with induction is similar to spontaneous labor. A score of 6 or less is considered to be unfavorable if an induction is indicated cervical ripening agents may be utilized. Many hospitals in Florida will attempt induction at a 6 OR LESS, which explains our high c-section rate.

If you are considering an elective induction or facing a medical induction with some wiggle room for negotiating a few more days before the induction is determined, it may be helpful to know your Bishop Score. Below is a chart you can use as a quick reference:

*For example, if you are 3cm, anterior, 60% effaced, -2 station and firm consistency, your score is an 7.

There are five parts to your Bishop score, but your provider will likely only mention 3. But that is enough to know whether or not induction is right for you!

The five components looked at are:

Position refers to the position of your cervix: posterior (0), mid-line (1), or anterior (2). Typically your cervix moves from a posterior position during pregnancy to an anterior position for birth. Your provider probably won’t mention this unless you ask.

Consistency refers to how soft your cervix feels to the touch: firm (0), medium (1), or soft (2). Your cervix tends to soften the closer you are to labor, which is why cervical ripening agents are applied as the first step to many inductions. Your provider may or may not give you this info, so ask if you’re interested in calculating your score.

Effacement is how thinned out your cervix is: under 30% (0), 30-50% (1), 60-70% (2), and over 80% (3). Your doctor will usually give you this information at routine vaginal checks towards the end of your pregnancy.

Dilation is the most well-known sign of labor progress, even if it’s not necessarily all that telling. The score is assigned: closed (0), 1-2cm (1), 3-4cm (2), and 5+cm (3). Your provider will definitely give you this information as long as you haven’t requested to not hear it. It is the part that most people focus on, but as you can see from this list, is not the only thing your cervix needs to do for a baby to come through it. It's a combo thing.

Station refers to where the baby’s head is in relation to the ischial spines (an imaginary line drawn across your pelvis basically) that indicates how low the baby’s head is (-5 being floating and not at all engaged to +5, which is crowning). Scores are assigned as: -3 (0), -2 (1), -1 (2), and +1 up (3). You may hear you provider call out this number during your check, but you can always ask to clarify.

Why To Avoid Induction If Not Medically Necessary

When labor is induced before the body is ready, chances increase for further medical intervention.

According to a study out of Stockholm, Sweden, among women who were induced, the proportions delivered by emergency cesarean section were 42% for nulliparous (first time mothers) and 14% for multiparous (mother of more than one birth). Compared to spontaneous onset, this corresponded to a more than threefold increase in risk for nulliparous women and an almost twofold increase in risk for multiparous women.

The main reason doctors give for scheduling an induction is being close to or past your due date. This way it is very important if you are birthing with an OBGYN that you find out how long they will "allow" you to go before inducing you. Most will only go to 41 weeks. Some 41 and 2 days. I personally only know four OBGYNs who will allow you to go to 42 weeks. Midwives (not including nurse-midwives) will typically let you go to 42 weeks before medically intervening. Knowing their timeline will allow you time to try and induce your labor naturally so the chance of medical intervention is much less.

In some situations where induction is being discussed, such as the baby being past the due date, a suspected large baby or low amniotic fluid, you may be able to put off the induction for a day or so if mom and baby are OK. If you are high-risk due to past miscarriages, stillbirth, placental issues, or other severe circumstance, being induced before 38 weeks is common.

Unfortunately, even when all is well, many hospitals and doctors will claim they need to schedule an induction. Of course, this will rarely happen on a holiday or weekend! But you may need to be a bit aggressive should you wish to avoid induction if your Bishop score is low. Educate yourself so you can advocate for yourself. Save this blog for future reference!

Sources:

National Center for Biotechnology Information

Evidence Based Birth