Know Your Pelvis

One obstacle to a baby’s birth can be when the bony pelvis is not an easy fit for the baby. What we mean by this is that the bony pelvis forms an opening through which the baby must pass, and some women may have a relatively small opening. You might be told that because you are short, or have small hands or feet, that you are small in that area. Your care provider might have determined that certain dimensions are smaller than the norm, or perhaps is expecting a large baby because the father is big.
What really determines whether a baby can move easily through the bony pelvis is the baby’s size, the mother’s ability to relax and work with her body, and time. Many women who have a “medically adequate” pelvis still have trouble getting babies through, often due to tension in the soft tissue, and many women who are told they are “small” have had large babies quite quickly. Whatever your personal size, we know that our information has helped many, many women to create as much room as possible in their bony pelvis during labor, because they now “know” their structure and how to influence it to their advantage.
Bony Pelvis Landmarks
Let’s first consider the bony pelvis. The bony pelvis is made up of:
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Hipbones. These include the hip blades, pubic bones, sit-bones, and the bumps at the back where they slightly overlay the sacrum.
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Sacrum. The large triangular bone at the base of the spine.
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Tailbone. Otherwise known as the coccyx.
As you can see, there are two large, identical bones that sweep around from back to front, where they join in the middle. These complete bones are called the hip bones. We are not going to use medical terms, rather common ones, but for our purposes we need to identify several parts.
Most people are familiar with the bony blades that stick out at the sides. We will refer to these as the hip blades. The hard bits that we sit on, at the lower back, will be called the sitbones. And then there are the parts at the front, where your pubic hair grows, which are called the pubic bones. Where these meet in the middle is an area of cartilage; this front section is known as the pubic arch. (Cartilage is softer than bone, and is further softened by birthing hormones.)
At the back in the middle, the hip blades are joined to, and slightly overlap, the top corners of the sacrum. There are two bumps where this happens.
The sacrum is the large bone in the middle there, shaped like an upside-down triangle. The two upper corners of the triangle are joined to, and slightly overlapped by, the hip bones. At the taper end of the triangle is the tailbone.
Inside the Hole
The outside of these bones are easy to feel, but it is the inner hole they create that is important to us. These four pelvic bones form a rough “circle,” and the space within that circle is called the pelvic opening. You can see this in the illustration on the opposite page. This opening has a top (medically termed the pelvic inlet); a middle (the mid-pelvis); and a bottom (the pelvic outlet). The inlet cannot be felt from the outside; its front is just above the pubic bone. The mid-pelvis can only be felt from the inside. The outlet, however, can be felt from the outside, and its shape is affected by body positioning. It is this opening through which a baby must pass during birth.
The illustration is only a guide. For one thing, a two-dimensional diagram doesn’t do the real thing justice. Secondly, everyone is different, and your shape and size might vary from what you see here. And thirdly, diagrams like these show only the bones.
In reality, the pelvic bones are held together by ligaments and tendons, attaching to muscles, and everything is covered and connected by connective tissue. This can make it difficult to find the bones in your own body, and determine their exact size and shape.
Our video (details included at the end of this article) will help you locate these bones in your own body (“The Bony Pelvis—Anatomy”) and then determine the unique dimensions of your pelvic outlet in “Mapping the Pelvis.” As it is impossible to feel all of the bony pelvis from the outside, we do the best we can, by mapping just the outlet.
Knowing the shape of your pelvic outlet will help you to understand how your baby might use the space within the bony pelvis to come through. Sometimes it will be difficult to feel these structures from the outside, and you will need to “perceive” certain areas which are not readily accessible to touch. Try to develop an overall awareness of your body to get as complete a picture in your mind as possible.
Mapping the Pelvic Outlet
When you map your pelvis, you will map the curve of the pubic arch, the distance between the sit-bones (side to side), the distance from the pubic arch to the tailbone (front to back), and the length of your tailbone, noting whether it curves under.
The map shows the way. We have found that when women “know” their own pelvis they are able to assume positions during labor which help to keep their pelvis open. Mapping your own unique pelvic structure provides valuable information on how to affect that opening, unlike blanket statements such as “squatting opens the pelvis.”
As labor progresses, some positions help open the soft structures as well. So how you position yourself in labor and birth can help or hinder your baby. We can honestly tell you that if your cervix dilates, and the baby has plenty of room to come through your bony pelvis, and you can easily open your birth canal, in reality you can be standing on your head and nothing will stop the baby from coming out.
The Soft Pelvis
Any kind of tension held in your body during labor can work against your baby’s efforts to be born. Tense up right now inside your belly and pull up “down there.” If your baby is trying to come out, does this tension help or hinder? Obviously, it hinders. It makes common sense to relax and soften in as many places inside and down there as possible.
Easier said than done, if you experience the naturally occurring pain of contractions. We all hold tension in the soft tissue of the pelvis—i.e., the muscles, connective tissue, tendons, and ligaments—any parts of the pelvis that are not bony and hard. We refer to all of these as the soft pelvis.
Body Skills will help you:
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Identify important parts of your soft pelvis.
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Appropriately prepare your soft pelvis for birth during the last period of your pregnancy, so you can remove as much internal tension as possible.
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Learn the skills to soften your soft tissue in the birth so you can help your baby’s efforts to move down, through, and out of your body, even when you feel the pain of labor contractions or during surgery.
The soft pelvis is out of sight, deep inside, so you will need to use your imagination to “look inside” to learn about where these important soft structures are and what they do. Then you will learn how to soften and relax these specific aspects of your body. Quite soon, you will feel certain that you can reduce tension and maintain relaxation inside your body.
Little by little, you’ll not only get the right image of the inside of our shared human body, but you’ll also be able to identify specific places in your own body and be able to reduce tension in any of those places.
These are the parts of the soft pelvis most relevant to birth:
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Uterus
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Cervix
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Pelvic floor
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Birth canal
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Perineum
In the bony structure of the pelvis, there is a hole/tube that has an inlet, a mid-section, and an outlet. Remember that we’re dealing with a real tube or doughnut-hole here, something you can travel through, not just a circle.
The birth process is a lot like a plumbing process that occurs between your baby (an “object”) and your body (a “container”).
The birth process involves these three steps:
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The cervix fully opens—the “diaphragm” of the plumbing.
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The baby moves through the tube of the pelvis— the “inside of the container.”
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The baby opens the birth canal (also called your vagina) to be born—the “aperture.”
The first two steps have a bit of a complex relationship. Sometimes, the baby moves through the pelvic hole, but the cervix doesn’t open fully. This is often called “failure to progress.” Sometimes the baby doesn’t even enter the top of the tube, yet the cervix fully opens. This is called a “high baby.” Most often, though, the baby moves through the tube and the cervix opens. This is called a “progressing labor.”
Step three can only occur when the first two happen. The vagina only opens once the baby has moved through the tube and the cervix is totally open. The vagina opens because the baby moves down and out of your body.
For most people, the cervix and vagina can easily be identified as “soft tissue.” You may not know yet where your cervix is, but you’re not likely to think it’s a bone. However, few people think the hole in the bony pelvis has much to do with soft tissue. In reality, lots of soft tissue surrounds every single bit of bone, and is in the places where the different bones of your pelvis meet. In our living body, there is absolutely no part of any internal bone that is exposed. Every single aspect of every bone is entirely surrounded with soft tissue.
If there is tension in your internal, pelvic soft tissue, your baby can find it difficult, or even impossible, to get through the hole in your pelvis, and you can have difficulty opening your cervix or vagina.
Birth skills will help you relax each part of your soft pelvis as the contractions work to open up the entire pelvic area. These skills will also help you manage the pain associated with the opening. When the modern maternity system evolved several generations ago, the initial goal was pain reduction, not problem management. Pain was considered too much. The pain of birth contractions is very manageable with the right skills.
The Pelvic Floor
Childbirth education classes often talk about the pelvic floor, but they might have a different meaning from the information we are about to outline here. Families who have developed birth skills have defined the pelvic floor casually, in a way any of us can understand.
When they talk about the pelvic floor, they are referring to:
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all the soft tissue of the top of the birth canal, including the cervix, as this attaches inside your pelvic tube,
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the walls of your vagina,
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the tissue between your vagina and rectum, and the tissue behind the rectum and to each side.
Exercise: Identifying Your Pelvic Floor
Both men and women can tense up all this extensive soft tissue.
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Tense up right now inside your lower belly. You may also feel a lot of other things tense up inside. You might not be too certain what specific parts you are tensing, and that’s okay for now. You don’t need to pay particular attention to exactly where you are tensing—just tense up inside.
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Now tense up all around your rectum.
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Now tense up as though you were holding back your pee midstream.
In simple terms, the pelvic floor is a fancy name for all of your vagina from the top part, including its walls and outlet. This space is the same as your baby’s birth canal. You’re just learning how to experience it in your own body.
This whole area is where a mother-to-be needs to relax in labor and birth, and even during the surgery of a cesarean to better reduce or limit emotional and physical trauma.
Pelvic Floor Retracts
The muscular wave of a contraction acts directly on all the tissue of the lower part of your uterus, which you now know is the top of your vagina, including the cervix. Since your cervix sits in the middle of all this tissue, and the outer reaches of this tissue connect to the inside of your pelvic tube, the wave causes the tissue surrounding the cervix to retract back toward the pelvic bones, first thinning the pelvic floor tissue, and finally tugging and opening the cervix.
Your awareness of this area can greatly influence the speed and efficiency of dilation. It is necessary for you to relax inside your pelvic bones so the cervix can open more easily, with a minimum of strain on the soft tissue. That’s why it is important to learn the Pelvic Clock and Cervical Relaxation skills. The former places your intentional softening all around the inside of your pelvic tube, while the latter focuses your attention on the 50/50 cells of your cervix.
Rethink Pelvic Floor Exercises
Since the 1970s, pregnant women have been taught and told to do as many pelvic floor exercises (PFEs) as possible. Most women know these exercises:
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Holding back your pee in midstream.
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The Elevator: Tightening up at the bottom, midpoint, and top of your vagina.
The reason women are told to do this is to strengthen the inside soft tissue that gets stretched by the weight of the baby during pregnancy—after all, a baby weighs quite a bit. The benefit of strengthening this internal soft tissue can prevent a possible future prolapse of the bladder, cervix, or uterus. Doing PFEs is accurate and right…but it has unintended, very negative consequences for giving birth. Tightening up inside is not proactive for preparing your pregnant body to becoming an efficient birthing body. Just tighten up inside like in the above exercise, and consider if your baby could easily open your cervix or move effectively down, through, and out of your body. Is doing PFEs hampering or helping the birth process? Tension down there absolutely, absolutely, absolutely hinders all stages of labor and birth.
As one father said after a very disappointing emergency cesarean, “My wife did hundreds of pelvic floor exercises. We were both proud at her ability. We both thought she would have the really, really strong muscles needed to push our baby out. It wasn’t until we got more involved with birthing better birth skills in our second pregnancy that we realized how wrong we were. My wife needed to open up to let our baby out!”
This does not mean PFEs are wrong. It means you have to do them at the right time, stop doing them at the right time, and do something else when you stop them. If you are early in your pregnancy or between pregnancies, feel free to do as many PFEs as you want.
But, from 24 weeks onward, you should stop doing them and learn to open up, soften, and relax. If you want to continue to do PFEs, do so only with the understanding that you’re doing them to keep your insides strong for the rest of your life and with a willingness to learn how to open, soften, and create space for your baby.
Becoming a parent is not just about you. You only need to soften and create space for a few months and for a very specific event, and then you can go back to tightening up. But do not make the mistake of ever thinking that being tight inside is positive for giving birth. Being tight and tense inside just compounds the potential to have a failure to progress. That’s common sense. Use your common sense to do the right thing, at the right time, for the right reason.
The Pelvic Clock
As is quite obvious, your pelvis is the area of your body most involved in birth. The Pelvic Clock is a great tool that targets this entire area. The benefits include:
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It extends your attention and awareness deep into your body, all the way to your cervix.
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It aids dilation by extending your ability to soften outward to where the soft tissue connects to the inside of the bones of your pelvis.
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It keeps the bones of your pelvis mobile, particularly your sacrum.
Exercise: Identifying Your Pelvic Clock
Use the image of “upper room” and “lower room” to identify the top of your vagina and cervix. Men don’t have a cervix, but they do have a pelvic floor, so they can target the same areas as their partners.
This room divider is shaped as a rough circle, like a clock face. You can now envision the tube formed by the bones of your pelvis to be like a frame around a clock, with the top of your vagina being the clock face and your cervix being where the hands of the clock meet.
Contractions tug open the place where the hands of the clock meet, causing the cervix to increasingly open until the clock face no longer exists. When this happens, your cervix will have been pulled into the sides of your bony pelvis. You are then 10cm dilated, and your baby will continue to move through the hole in your pelvis and into the lower room, your vagina.
Exercise: The Pelvic Clock
This exercise works with the inside of your bones and the tissue attachments there. You will begin to feel where you store or collect tension. Tension gets created because, as humans, we stand and walk, which creates tension in our pelvis.
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You can call each area of the pelvic clock by name: the pubic bone 12 o’clock, the sacrum 6 o’clock, one hip 3 o’clock, the other 9 o’clock, etc. You want to soften in each of these areas, letting go of any tension you might have. Do this in every posture and position.
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If you can’t feel any softening, first tense up and then soften specific areas. You don’t want intentional tensing up to be your goal, but sometimes it takes creating more tension during practice for you to get the subtle feeling of softening and develop your confidence. It’s okay to do that now and then during labor, too; just don’t make a habit out of it.
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Come back again to this exercise with the addition of breathing skills, then you can go around your pelvic clock, expanding inside your pelvic clock on each inhale, and softening and relaxing inside your pelvic clock on each exhale. During labor, if you feel pain/discomfort in your sacrum, hip, or pubic bone, it might be caused by your baby’s pressing against the bones, and pain in the uterus is often just due to the cervix dilating. Your purpose in doing the Pelvic Clock is to make certain that, when the wave of a contraction pulls on the cervical muscle, there is no tension either at the tissue attachment where your pelvic floor meets your bones, or in the muscle itself. This is your goal, even when you’re in pain.
Side Note for Cesareans
The Pelvic Clock exercise was developed by hundreds of women who absolutely knew (after the fact and during labor) that they did not know how to relax and soften inside their pelvis. Coupled with Directed Breathing, the Pelvic Clock creates a major focus tool throughout labor. As it has become more widely adopted, it has done much to reduce surgical births that come from all forms of delay in the first stage of labor.
If you do have a cesarean, because you’re numb from your waist down and there is a cover put up to prevent you from seeing the surgery, it is very, very easy to disconnect from your body for the short period of surgery until your baby is born. This disconnect is a passive state and can negatively impact your sense of continuity from being pregnant to giving birth, finishing the birth, recovering from the birth, and moving into parenting.
We are designed to do the whole process. No matter what reason incites your surgical birth, it is within your ability to maintain that continuity. You do this by using skills such as the Pelvic Clock. You’ll be given an epidural, so you won’t feel anything. However, your head can still mentally soften and relax this area.
For the Father/Coach
It often is very helpful if you touch an affected area to remind your partner where to soften, and there are skills to learn to better do this. Also, you can learn communication skills and how to verbally cue your partner to keep going around the inside of her bony structure, softening and relaxing each individual area.
Once you truly recognize birth as an exercise in plumbing and which parts must stay open and relaxed, you will feel totally comfortable in advising your partner. You’ll be sensitive to seeing whether she is unintentionally creating tension, and you’ll be able to hear whether her breathing indicates she needs support and assistance in softening, rather than tensing. She wants your help! The internal relaxation is something you can feel, as well.
Common Language for the Pelvic Clock
For the Birthing Woman
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If you see me tensing up, please remind me to use the Pelvic Clock.
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Please just put your hand here. (You show your husband/ coach. Often, no words are necessary; just place their hands where you want them.)
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I can’t always relax as the contraction gets more painful.
For the Father/Coach
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After each contraction, go around the Pelvic Clock and relax any tension that has built up.
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Let me touch around your pelvis, and you just soften under my touch.
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If you have pain somewhere inside, just take a deep breath in, and then when you exhale, let go of the tension in that specific area.
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Let me know where you feel the pain and I’ll remind you to relax, or I’ll touch you there, so you can focus on relaxing there.
If you forget how to relax inside, tighten up first and then relax. Not only does the Pelvic Clock induce relaxation, but it also is a great tool for encouraging progress and for focusing, even if you experience pre-labor, false labor, or a non-progressing labor, where the Pelvic Clock can help to:
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Give you something to do until your body establishes a good labor pattern.
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Get you familiar with the pattern of contractions. Begin your default behavior, using skills throughout each moment of your labor experience, both during contractions and the space between. Once your labor contractions get established, your job is to keep your labor progressing. You do this best by paying attention to the details of your body, constantly reviewing specific areas to make certain your soft tissue is relaxed and softened. With enough practice, this becomes so automatic that you almost forget you weren’t born with these skills. But it takes focus!
At any moment during a contraction, even if you feel overwhelmed, the Pelvic Clock is a skill that will help to restore your focus and control. Together with other birth skills, such as breathing skills, you will recapture your energy and direct it to the task of dilation. (For more details into this skill and to see the accompanying video, visit birthingbetter.org.)
Cervical Relaxation
A closed (undilated) cervix is like when you purse your lips together tightly and try to get your little finger into the hole. If you open your mouth as wide as possible, that’s the size of a cervix that is about 4 to 5cm dilated. You need to be at 10cm to be fully dilated! It’s like putting a turtleneck shirt over your head.
When full dilation happens, your cervix has virtually disappeared by pulling back into your bony structure. Remember, that’s equal to putting your two thumbs and two index fingers together and making a circle. Your cervix might behave in three ways during the first stage of labor:
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Dilate evenly over time; approximately 1 cm every 2 hours.
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Barely dilate over most of first stage, until it suddenly opens quickly right at the end of the first stage and then the second stage happens. Thirty percent of women have this happen. Contractions in this type of labor still come closer together, grow stronger, and last longer. In other words, the labor contractions are progressing, yet the cervix isn’t yet dilating.
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Stop dilating for a period of time and reach a plateau; another kind of “failure to progress.” Contractions in this type of labor remain the same. They do not get longer, stronger, and closer together.
Those second and third possibilities are often caused by internal tension that women don’t know they have and haven’t been taught how to reduce, or that they even need to reduce it. Any tension can hinder the effective birthing process.
The benefits to the Cervical Relaxation exercise are:
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It encourages the cervix to dilate more rapidly if it’s taking its sweet time.
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It helps the cervix to resume dilation if it’s stopped altogether.
Exercise: Cervical Relaxation
Steps for the coach:
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Your doctor or midwife can tell you how dilated the cervix is, if you are unsure. If the birthing woman is stuck at 4cm, that’s roughly a hole you can stick four fingers into.
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Use your finger to draw a circle the size of the current dilation on the top of your partner’s head OR on top of her kneecap. This works particularly well on top of the head, especially if her chin is tucked, because that’s exactly what your baby is experiencing. Remember the turtleneck analogy.
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Once you’ve drawn the circle approximately the size of the opening in the cervix, touch the part of that circle that’s to the back of her head and tell her to expand inside on that area with the inhale, soften with the exhale.
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Move around the circle, touching different points, having her soften inside corresponding to each place you touch.
Steps for the birthing mother:
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As the cervix opens, there are more areas on the cervical rim that you can relax.
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If nothing seems to change, do it again 30 minutes later. How will you know if change is occurring? The contractions will pick up and become more effective, and perhaps more painful. Use your skills to cope.
This is basically the same exercise as the Pelvic Clock, but instead of softening around the outer face of your pelvic clock (inside your bones), you are softening around your cervix (the middle of the tissue). Do this throughout labor, as well as during the last two weeks of pregnancy. It can really help! As with all skills, the aha! moment comes only if we practice.
For coaches or husbands, if your partner has difficulty dilating, you can have a huge, positive effect in helping her soften and relax the cervical muscle and get the dilation happening again. Expect contractions to become more intense, because that indicates that the tissue of the cervix is being effectively pulled back onto the hole in the pelvis. For more elaboration on the above skills and many others, visit BirthingBetter.org and seek out other skill-based methods.