Wednesday, June 15, 2011

Opening the Back

Jamaican midwives having a saying that when the back opens the baby comes. This is referring to the period of time around the fetal ejection reflex where the baby moves down to crowning and birth. Opening the back occurs when the sacrum moves backward to allow more room for the baby to move through the pelvis. Its amazing to learn how much space is gained by this--up to 4 cms in some places! I had never come across it before in any of the other reading I have done on birth. I thought this is so cool, I can share it here. Especially since I can even tell a personal story about it.

I encountered this term in my copy of Holistic Midwifery Volume II written by Anne Frey. It is one of the texts in my midwifery program and covers extensively (its almost 2,000 pages!) the physiology and care of labor and birth.

I remember when this happened during Belle's birth. I even commented on it when I wrote her  birth story. I didn't know the name of it then so I'm pleased to learn about it now. At the time I described it as:
I felt tightness radiating down into my thighs and it felt like the bones of my pelvis and hip were being stretched outwards.
I later thought that this might have something to do with the hip pain that lingered after that pregnancy. I learned that it might be SI dsyfunction (sacroiliac joint) and posted about it here. Finding out that it was an actually physiological process that is part of normal birth helped me feel that the strange sensation wasn't an injury but my body working as it was designed to.

I thought at the time that when I felt my hips spread during Belle's birth that something unnatural had happened. I still think that maybe my SI issues have something to do with this spreading. It happened so quickly--it was like my SI joints abruptly slid out as far as they could like sticky slide locks on a door. Perhaps they slid more forcefully and quickly than is typical when the sacrum moves and the back opens.

This phenomenon is only observed when upright birth is allowed. When a woman in laying on her back in bed, the sacrum is prevented from moving and the pelvis does not expand in conjunction with the fetal ejection reflex.

I don't recall feeling this happen when giving birth to my son. Not surprising, since I felt pressured into birthing on my back. The only way I felt that I had been able to reposition more comfortably as he was descending and crowing was by twisting my hips so that I was more on my side.

Someday I may find more detailed description of this phenomenon. It seems like it hasn't been described or investigated by researchers enough to know what is normal "opening of the back" and what is extreme. As it is, the term is hardly known except in some circles. Hospital birth attendants and medical researchers wouldn't see it because the vast majority of birthing women they see are on their backs. Upright/vertical birth isn't even an option in many hospital birth environments.

Have any of my readers heard of this? Care to theorize with me on the possibility of normal opening of the back and extreme opening on the back?


Rixa said...

Oh yes, I've definitely heard of it and been there when it happened. I never noticed it myself, but at one birth I attended as a doula and midwife's assistant, the woman was pushing (kneeling, in a birth tub) and said "I feel my hips opening" as her baby descended. The baby was born just a few minutes later.

Shawnette said...

My physical therapist told me about this when I was pg with G-I assumed at that point it was pretty common knowledge, though I hadn't even known there WERE SI joints until then. During one of my first doula births where mom had MANY hours of back labor and her only relief was my fist shoving against her sacrum, I was the one who was able to announce we were finally making good progress, as her sacrum started fighting back and she wanted counterpressure at lower and lower points. I have felt it in other women, too, if I happen to have a hand or a fist on a tailbone during "final decent". It's pretty cool. When birthing Kiera I was unable to assist pulling her out because I had to use both fists to lift myself off the floor of the tub to allow for my own back to open.

Aerin-sol said...

You might find these links interesting.

Natalie P. said...

I had this TRY to happen to my body. Unfortunately, I have arthritis in my sacrum, and my body couldn't do what it is naturally. It also hurt so badly I begged for an epidural during transition. I delivered my son less than 45 minutes after getting the epidural, it was intense.

Jenne said...

Oh Natalie, that does sound intense. And painful! That sounds like a highly appropriate time to make use of an epidural. I'm glad it provided the relief you needed given your situation.

Shawnette, that is so cool to have been able to observe and witness that.

Natalie P. said...

Jenne, it totally was. HOWEVER, I refused to do further damage by laying on my back.

With epidural catheter in my back and all, I delivered my 9 pound 3 ounce son in a supported squat!!

And people say that once you have an epidural you can't move, HA!

Jenne said...

Thanks for adding that! I love hearing stories like that. I'm so glad you can tell that story so more women know that epidural does not equal immobile!