The posture will be adapted to the rapidly changing load during pregnancy. The body takes the path of least resistance. Some muscles are shortened and others are prolonged. This leads to many pregnant women having similar posture patterns, often called sway back.
Sway back means that the weight is placed on the heels instead of being evenly distributed over the front and the back. The knee will be hyperextended, the pelvic posterior tilted and the lordosis moved higher up in the back to the transition between the thoracic and lumbar spine. Furthermore, the thoracic flexion will increase and the shoulders and the chin will be pushed forward. This also leads to the shape of the neck called buffalo hump.
The hamstrings will be shorter because origin and insertion will come closer to each other when the pelvis is rotated backwards. This will cause the glutes to become less active and the hamstrings to be more active. An active muscle is also stiffer, and will thus reinforce the sway back. Since the glutes becomes less active, it will not be used in the same amount and therefore decrease in size. Many who have been pregnant can feel that the glutes disappear during pregnancy. This is the explanation!
Perhaps you as pregnant have also experienced that your back feels tired? There are several reasons; the baby grows and you get heavier, your posture changes, you get less contact with the abdominal muscles and a reduced activity in the glutes. The glutes are very important for relieving the lumbar muscles, and as mentioned above, the seat is extended and weakened and the requirement for the lumbar muscles increases.
During pregnancy, the abdominal muscles will also change in appearance and function.
In order for a baby to fit, the connective tissue of the straight rectum abdominus must be expanded and divided. The widening can persist if the elongation has been high and if the load soon after birth has been too high or incorrect. This widening is also called diastas.
When thoracic kyfosis is increased, the origin and the insertion of the muscle rectus abdominus will come closer. It creates increased activation, which in this case is not beneficial since the muscle is already divided.
The Erector Spinae are prolonged as the pelvis is backward tilted and the origin and the insertion of the muscles come further apart. When the muscles grow long, they also become weak with impaired stamina and you get tired as a result.
The changing posture with increased thoracic kyfosis will cause the scapula to slide forward even further. As the scapula slide forward, the glenohumeral joint will also end up in a new position. This can cause pain in the shoulders and neck.
In summary, a chain of compensatory posture patterns occurs to adapt to the fast-growing stomach. To reduce these compensatory patterns, one should insist on working with the posture and not allowing the body to reduce the path of least resistance.
In the next article, you will get a more detailed description of how the abdomen muscles are affected during and after a pregnancy and child birth.