Low Back Pain and Pregnancy
Low Back Pain
There are 24 independent vertebrae in the
7 in the cervical region, 12 in the thoracic
region and 5 in the lumbar region.
The lower lumbar vertebra is attached to
the sacrum which is a bone consisting of
several vertebrae fused together.
This area around the lumbar spine and
sacrum is the most common site for back
pain due to the instability caused by the
changing curvature of the spine in this
Between each vertebra is a disc designed
to reduce the frictional and compressive
forces between the bones.
Causes of Low Back Pain
Lowerback pain is one of the most
common illnesses experienced by humans
and usually is associated with the aging
process. However, aside from the natural
aging process there are several different
causes for lower back pain
Causes of Low Back Pain
Lower back pain could be a result of
Spondylolysis or spondylolisthesis *
Lumbar disc injury/degeneration
General disc disfunction
* Spondylolysis is the occurrence of a stress fracture to the spine. If
the stress fracture worsens and the vertebra can no longer
maintain its position and shifts it is known as spondylolisthesis.
Low back pain caused by a muscle strain involves tears
to the muscle fibers in the muscles surrounding the
spine. This condition is quite common and can be
caused by a number of things but is usually caused by
trauma or by overuse.
If the strain is caused by trauma the affected muscle
must go through the three phases of soft tissue healing
and rest is usually prescribed. The three phases of soft
tissue healing are:
The acute inflammitory phase
The proliferative/ repair and regenerate phase
The maturation/ remodelling phase
The entire healing process can take up to one year but the majority
of healing is complete within the first two weeks and a return to
normal activity is usually permitted at this time.
If the strain is caused by overuse it is required that the
cause of the incorrect movement patterns be corrected.
Retraining the muscles and improving posture will also
help prevent further injury. Once the cause has been
corrected rest may be prescribed.
The muscle does have to go through the phases of soft
tissue healing but if the initial cause is not corrected the
muscle will not heal.
If the overuse injury causes a stress facture in the
vertebra it is known as spondylolysis. If the fracture is
not treated and worsens the vertebra will become
unstable and shift causing a spondylolisthesis.
Progressive Disc Degeneration
Low back pain caused by disc degeneration involves a
decrease in the function of the intervertebral discs.
Disc degeneration occurs in all humans as a part of the
natural aging process that causes an overall decrease in
collagen and water levels in the body.
The disc is made up mostly of collagen and water and is
divided into two parts; the annulus fibrosis and nucleus
pulposa. The nucleus pulposa contains a highly hydrated
matrix filled with collagen making it particularly
vulnerable to the aging process.
The loss of fluids and collagen causes the disc to
compress thus no longer providing the cushioning to
absorb the forces placed on the spine.
Progressive Disc Degeneration
Although the natural aging process is to blame
for some degeneration, improper posture can
worsen the problem.
Improper posture causes a change in the
biomechanics of the spine. This causes undue
wear and tear to the disc adding to the loss of
Also, the accumulation of debris in the disc
because of enzymatic dysfunction can
accelerate the degenerative effects. There is
little that can be done to prevent this but proper
posture and maintaining hydration are good
ways to lessen the negative effects.
Medications- analgesics, muscle relaxants, and anti-
Decreasing physical activity- especially contact sports
Exercise- within limits
Contraindications for Exercise
Passive lumbar flexion
Active lumbar extension
Stretches that call for the knees to be
brought towards the chest
Also avoid any exercise that does not
provide adequate support or the lower
* It should be noted that the cause of the pain needs to be
examined by a physician before a person can begin
exercise to avoid making the pain worse
Pregnancy begins the moment a sperm fertilizes a
woman’s egg or ovum. The average pregnancy lasts 40
weeks (roughly 9 months). The 9 month period is divided
into three equal time periods of about 3 months called
During the first trimester there is little change in the
mother’s body however this is a critical period for the
At the beginning of the second trimester the physical
changes such as weight gain begin to become evident in
The third trimester is the period of most rapid fetal
growth which corresponds with the period of most
extreme change in the woman’s body as she prepares
for the birthing process
Changes to the Woman’s Body
Many changes occur within the woman’s body to
prepare her for the birthing process. The
following changes are a concern when
prescribing exercise to pregnant women.
Hormone release resulting in joint laxity especially in
the pelvis and lower back
Weight gain concentrated in the abdomen resulting in
a forward shift of the center of mass
Changed body composition resulting in an increased
Weight Gain during Pregnancy
Weight gain during pregnancy is the most drastic
of the changes a woman experiences as she
can gain anywhere from 15 to 40 pounds by the
end of the third trimester. The weight is
distributed unevenly (most goes to the belly
area) causing a shift of the woman’s center of
mass anteriorly. The copious weight gain is one
of the main motivators for exercise during
pregnancy as it can have negative effects such
as low back pain, fatigue and weight retention
after the birth.
Reasons for Exercise during
Thereare also several other motivators for
exercise during pregnancy including:
Feelings of self-consciouness about the
Concern about having a healthy baby
Desire to stay in shape
Want to be able to handle the physical rigors
of labor and delivery
Social interactions and support
Benefits of Exercise
Improved cardiovascular and muscular fitness
Facilitated recovery from labor
Faster return to pre pregnancy weight, strength and
Reduced post partum belly
More energy reserve
Fewer obstetric interventions
Shorter active phase of labor and less pain
Less weight gain
Enhanced maternal psychological well being that may
reduce feelings of stress, anxiety, and depression often
experienced during pregnancy.
Increased likelihood of adopting permanent healthy
Exercise Specifics for Pregnant
Moderate exercise sessions are advised because research has
shown that there is a link between reduced birth weights in babies
whose mothers performed high-intensity exercise throughout
pregnancy by 300-350grams (10-12 ounces) on average. Also there
was an increase in fetal heart rate in babies whose mothers who
performed high-intensity exercise during pregnancy by 5-15bpm on
average. Rating of perceived exertion should be used to determine
moderate exercise levels.
Should use weight machines which provide more stability and
support than free weights.
Back lying (supine) position may result in restricted venous return of
blood because of increasingly large uterus. Women should perform
more exercise on their side or hand and knees, then on their back.
Pelvic floor exercises (kegels) are another important element of
resistance training during pregnancy. This involves tightening and
relaxing muscle groups in the pelvic region which will help with
delivering the baby.
Although exercise is most often beneficial
there are three key concerns for potential
Insufficient oxygen or energy substrates to the
Hyperthermia- induced fetal distress or birth
Increased uterine contractions
Contraindications for Exercise
A pregnant woman experiencing any of the following should avoid exercise
Pregnancy induced hypertension
Premature labor during the current pregnancy
Persistent bleeding after 12 weeks
A cervix that dilates ahead of schedule
Multiple birth pregnancy
A placenta that blocks the cervix after 26 weeks
Extreme low body weight
History of a very sedentary lifestyle
Discontinue exercise if:
Any signs of bloody discharge
Swelling of ankles, hands or face
Headaches, fainting, dizziness
Swelling, pain or redness in the calf of one leg
Increase pulse rate or blood pressure that
persist after exercise
Unexplained abdominal pain
Insufficient weight gain
If any of the above should happen it is important that the
woman seek medical attention immediately.
30 minutes of moderate exercise 5-7 days per
week including both strength training and
some aerobic conditioning
Age-predicted HR targets are less reliable
during pregnancy. Thus, a talk test or Borg
scale is a better predictor of intensity.
It is very important that pregnant women
consult with a physician before beginning an
exercise regimen to ensure that exercise is
healthy for both the mother and child.
Thank you for your time.