Chiropractic and Birth

For the sake of this post we will only discuss pelvic floor and mechanistic views of the pelvis for labor and delivery. There is A LOT more at hand, but this is the best entry point for what will later prove to be a pretty complex relationship.

Round Ligaments
These are best described as the ropes that tether the top of a hot air balloon. Before conception, these ligaments sort of hang off the top of uterus like arms. The fibers of the round ligament actually descend so far as the labia majora (external female genitalia). As the uterus expands to accommodate the growing baby, the round ligaments look like the ropes that go over the top of the hot air balloon keeping it on the ground.

This balloon is tethered, and look how roomy it is! This is what we want the uterus to look like. If a woman has a traumatic pelvic trauma like falling off of a bike, falling off of a horse, even some hard falls when she was a baby, these ligaments can have different tensions. This would lead to something like this:

This is an exaggeration, but our goal is to give baby as much room as possible to flip and flop and wiggle around all they want until the time comes to get serious. Then, when it's time to get serious we want baby to engage and exit with as much ease as possible, for mama and baby.

Sacrotuberous ligament
This ligament deserves a regal entry. This dude is the unsung hero of all pregnancy. So, the sacrotuberous ligament makes a lot of things work: it attaches the spine to the leg (sacrum to biceps femoris, aka major player of the hamstrings), it protects the pudendal nerve (responsible for muscle tone in the perineum--wowzas!!), contains branches of the gluteal artery, Similarly to the round ligaments, if a woman has pelvic trauma, this ligament can lose it's flexibility, thus preventing the pelvis from opening properly during labor.

Sacrospinous ligament
The fibers of the sacrospinous ligament are integrated into the sacrotuberous ligament, but this job of this ligament is to essentially create the greater and lesser sciatic foramen. If you have ever been pregnant, and developed sciatic-like nerve pain...this ligament could be a contributing factor. Again, this ligament, as it is so closely related to the sacrotuberous ligament is going to have heavy influence on the pudendal nerve, which is the nerve that helps determine the muscle tone in the perineum; if the perineum is taut, you are more likely to have perineal tearing and postpartum incontinence [1]

Abdominal muscles
The abdominal muscles are an accessory in birth. While the myometrium of the uterus is responsible for the actual contraction, the abdominal muscles are there for backup and extra "oomph". Guess where the insertion of 2/3 of the abdominal muscles are? Either directly on the vertebrae in your spine, or on the tissue that is attached to those vertebrae,

Pelvic girdle
The Pelvic girdle consists of muscles, bones, and ligaments of the pelvis that ideally open symmetrically to allow baby to exit. Pelvic girdle pain is exceptionally common in the last trimester and up to 16 weeks postpartum. Many of the muscles in this area are innervated by the pudendal nerve. Previously we said that the pudendal nerve was closely related to the sacrotuberous ligament, and that between the round ligament, the sacrotuberous ligament, and the abdominal muscles, the attachment sites for all of these are either on the spine or directly to the bones of the pelvis.

So what does Chiropractic have to do with any of this?
Chiropractors who specialize in pregnancy should know how to address all of these ligaments and bones. Our pelvis is responsible for keeping us moving. Think of it in terms of survival; our arms are held on by a flimsy articulation and 4 main muscles. You can lose an arm and still get away from the lion chasing you.Your legs are held on by one solid ball in socket articulation; in our body this is the most stable a joint can get and still move. Beyond that, there are at least 5 ligaments and 4 muscle groups (multiple muscles working together) to keep your leg on; because you need the leg to escape the lion. So then amplify that by a million, when we incorporate a mother's protective reflex, and you begin to realize the significance of this hammock that we make while pregnant.

1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3279110/