Antenatal Postural Changes, Pain Prevention and Management.

Antenatal Postural Changes, Pain Prevention and Management.

Pregnancy is a magnificent process in which the female body undertakes huge changes and adaptations to grow and support a new life.
There are extensive  physiological and biomechanical adaptations to provide a suitable environment for development of the foetus as well as preparing the mother for labour (Yousef, A., et al 2011). Hormone changes and an increase in body mass from the expanding uterus cause a shift in the mother's centre of gravity resulting in additional dynamic and static loads on the axial skeleton (Casagrande, D., et al 2015).
The most common musculoskeletal complaints during pregnancy are lower back pain (LBP) and/or pregnancy-related pelvic girdle pain (PPGP).
Hormonal changes causing ligamentous laxity and the anterior shift in mass can lead to hyperlordosis of the lumbar spine and anterior tilting of the pelvic girdle (Casagrande, D., et al 2015).
The National Institute for Health and Care Excellence (NICE) guide Antenatal Care for Uncomplicated Pregnancies (2008) are surprisingly sparse on postural changes and musculoskeletal pain advice. While back pain is included in the guide's Management of common symptoms of pregnancy section, the guidance is limited to:
"Women should be informed that exercising in water, massage therapy and group or individual back care classes might help to ease backache during pregnancy".
Up to 76.4% of women are diagnosed with PPGP (Kanakaris, N., et al 2011) and 71.4% with LBP during pregnancy (Casagrande, D., et al 2015).

The hormone relaxin is known for encouraging ligament laxity in pregnancy but is also important in preparing the endometrium for early pregnancy (Goldsmith, L., et al 2009). While many studies believe that there is a correlation between serum relaxin levels and LBP/PPGP, a 1997 study of 455 pregnant women with clearly defined pain in their pelvic joints and 455 normal pregnant controls, showed no difference in serum relaxin concentration between the control and study group, nor between the subgroups of women with pelvic pain (Albert, H., et al 1997). 

This article is aimed at educating people on the musculoskeletal conditions associated with pregnancy, help women prevent or manage the symptoms for a less stressful pregnancy.

If you experience any pain during pregnancy you must inform your health practitioner.
It is advised you speak with your health practitioner before undertaking any of form of exercise while pregnant.
First trimester.

The first trimester (weeks 1 to 12) is commonly associated with morning sickness, cramps and cravings but in some cases women also report lower back pain within the first month (Sabino, J., et al 2008).

During the first trimester the pelvic girdle rotates slightly posteriorly.  This adaptation is caused by displacement pressures of other organs. Further to this the weight of the uterus is primarily taken by the bladder and pelvic floor muscles. This posterior pelvic rotation puts tension through the hip flexor muscles (quadriceps and iliopsoas), postural lumbar erector spinae mucles and upper abdominal muscles. As the uterus enlarges it continues expanding vertically moving the small and large intestine superiorly. This causes pressure to the diaphragm resulting in extension of the dorsolumbar region of the spine (Stone, C., 2007). The expanding uterus and tight iliopsoas muscles may also put pressure on nerves and blood vessels to the legs. The mother's breasts may become swollen and tender as the mammary glands prepare for milk production.

As a result of these changes abdominal pain, back pain, and leg or foot cramps may occur during the first trimester, though are more prevalent towards the 12th week. Given the naturally high risk of miscarriage during this phase, pain management techniques need to be treated with caution. However, some preventative methods are less invasive or stressful on the body so carry less risk:

Hydration is always important in good health. By drinking water (little and often) the fluids are able to nourish the tissues, lubricate and cushion the joints.  
Gentle movements such as walking or light swimming can prevent and help ease joint pains.
Warm (not hot) baths are also helpful for relaxing muscle tension and tightness. 
Elevating the legs and gently stretching the calf muscles can help prevent and ease the cramps.
Wearing an non wired or sports bra can prevent further irritation of the swollen breast tissue.

Aspirin and anti-inflammatory drugs such as ibuprofen or neurofen should not be taken during pregnancy but if the pains persist continuously throughout the day it is advisable to contact your health professional for examination and other pain relief options.

Second trimester.

From week 13 to 28 morning sickness symptoms often subside. The mother's breasts may be less tender but can grow significantly as the mammary glands begin to produce milk.
During the second trimester the uterus is expanding both upward and anteriorly and the centre of gravity gradually moves forward, causing pressure on the abdominal wall and diaphragm, loading of the lumbar spine and in many cases anterior pelvic rotation (Stone, C., 2007). The lumbar spine can begin to extend lessening the tension though the lumbar erector spinae muscles but loading them with weight of the growing uterus. This can cause the pelvis to rotate anteriorly, lessening the hip flexor tension and tightening the hip extensor muscles (hamstrings) on the posterior aspect of the thigh. 
The upward pressure on the diaphragm may give the sensation of breathlessness during and after exertion. The dorsolumbar region of the spine may begin to flatted and become immobile causing an upper breathing pattern which recruits the accessory breathing muscles such as the scalenes, causing neck pain and in some cases headaches..
With these adaptations, discomforts such as back pain (both upper and/or lower), neck pain, shoulder pain, leg cramps, pelvic pains and abdominal pains may occur.
During this phase the risk of miscarriage has lowered to 0.5% though is higher with previous miscarriage and deliveries (Westin, M., et al 2007). LBP/PPGP is more commonly reported from week 24 to 36 (Kanakaris, N., et al 2011).
Advice from the first trimester continues to be helpful for the second, but additionally:

Wearing low heeled comfortable shoes can reduce back pain by preventing further extension of the lumbar spine.
Sitting upright in a well supported seat to prevent slouching or further irriation of the back and hip muscles.
Sleeping on your side and tucking a pillow or duvet between your knees is helpful in easing spine and pelvic girdle pressure.
Wearing a larger supportive bra helps reduce upper back, shoulder and neck pressure from the weight of the growing breasts.
Practicing diaphragmatic breathing can reduce the use of accessory breathing muscles, improve sleep (if practiced in bed at night), reduce stress and regulate blood pressure.
Antenatal yoga classes can provide tailored exercises to help strengthen the erector spinae muscles, reduce muscle tension and improve pelvic floor tone.
Osteopathic treatment can reduce discomfort through gentle manouvres such as articulation, massage, joint mobilisation and muscle energy techniques.

Third trimester.

During the third trimester the uterus continues upwards until the last weeks, where the fundus (top of the uterus) drops anteriorly due to relaxation of the abdominal wall. The uterus then expands outwards (Stone, C., 2007). This additional load on the axial skeleton causes the classic lordotic or swayback pregnancy posture where the lumbar spine extends pulling the sacrum in to nutation and further rotating the pelvis anteriorly. As the mother's body prepares for parturition (labour) the joints increase in laxity, especially the sacroilliac and pubic symphysis joints of the pelvic girdle. This adaptation often allows for pelvic imbalances which justifies why  PPGP is most commonly reported during the third trimester.  The pelvic floor muscles will stretch and elongate with the increasing pressure and can weaken leading to incontinence. 

This increased laxity and weight gain not only affects the axial skeleton but can also affect the joints of the lower limbs.  An anteriorised centre of gravity and increased mass can cause gait alterations. The hip, knee and ankle joints may adapt to support the weight shift and can become painful, especially in the last few weeks of pregnancy.

In a study to examine the kinematic and kinetic adaptations women experience when exposed to increasing anterior mass, a 20 pound anterior mass caused a decrease in peak hip extension angle. Further to this an increased knee abduction angle was seen around toe off phase, suggesting a limb shortening strategy to increase foot clearance while walking.  An increased peak flexion of the knee at heel strike, is an additional compensation to pull the center of mass forward in the heaviest condition. In the heaviest condition an increased peak plantar flexion of the ankle during mid-stance could occur to propel the body with the additional mass (Ogamba, L., et al 2016). 

Incontinence, muscle fatigue, discomfort in the back, pelvis, hips, knees and ankles as well as sleep disturbance can occur during the third trimester as a result of these changes. The advice from the previous two trimesters remains suitable with the addition of:

Using manual handling methods (bending the knees with a straight back to lower the body) to lift objects from anywhere beneath your hip height prevents additonal spinal loading with the additional mass.
Kegel exercises, which strengthen and tone the pelvic floor muscles (that support your bladder, bowels, uterus  and aids in positioning your baby’s head during delivery) can help lessen the risk of late pregnancy, hemorrhoids or urinary incontinence.
Using an exercise ball to perform pelvic tilts and hip circles can help with reducing tensions in the lower back and pelvic girdle muscles as well as balancing and preparing the pelvis for labour. Speak to a health advisor or antenatal therapist for advice on how to perform these movements.
Lower back stretches such as the cat stretch or child's pose can help relieve lower back, pelvic and hip tension. Speak to a health advisor or antenatal therapist for advice on how to perform these movements.
Consideration of birthing options and pain relief during parturition. This can be discussed with your health professional or midwife.


During pregnancy a woman's body works at an optimal level to provide immunity, growth nutrition and support for both the mother and the developing foetus. By giving the body's musculoskeletal framework the support it needs during the adaptations, discomfort can be avoided or reduced to make this beautiful creation of life more enjoyable for all involved. A balanced diet, good hydration, gentle exercise and an understanding of postural changes are all factors which can make pregnancy less stressful. By advising methods for pregnancy-related musculoskeletal pain prevention and management, more families will be better informed - potentially allowing them to have happier, healthier  pregnancies.


Albert, H., Godskesen, M., Westergaard, J., Chard, T. and Gunn, L. (1997). Circulating levels of relaxin are normal in pregnant women with pelvic pain. European Journal of Obstetrics & Gynecology and Reproductive Biology, 74(1), pp.19-22.
Amal M. Yousef, I. (2018). Postural Changes during Normal Pregnancy. [online] Available at: [Accessed 8 Jan. 2018].
Casagrande, D., Gugala, Z., Clark, S. and Lindsey, R. (2015). Low Back Pain and Pelvic Girdle Pain in Pregnancy. Journal of the American Academy of Orthopaedic Surgeons, 23(9), pp.539-549.
Goldsmith, L. and Weiss, G. (2009). Relaxin in Human Pregnancy. Annals of the New York Academy of Sciences, 1160(1), pp.130-135.
Kanakaris, N., Roberts, C. and Giannoudis, P. (2011). Pregnancy-related pelvic girdle pain: an update. BMC Medicine, 9(1).
Ogamba, M., Loverro, K., Laudicina, N., Gill, S. and Lewis, C. (2016). Changes in Gait with Anteriorly Added Mass: A Pregnancy Simulation Study. Journal of Applied Biomechanics, 32(4), pp.379-387.
Sabino, J. and Grauer, J. (2008). Pregnancy and low back pain. Current Reviews in Musculoskeletal Medicine, 1(2), pp.137-141.
Stone, C. (2007). Visceral and obstetric osteopathy. Edinburgh: Churchill Livingston/Elsevier.
Westin, M., Källén, K., Saltvedt, S., Almström, H., Grunewald, C. and Valentin, L. (2007). Miscarriage after a normal scan at 12-14 gestational weeks in women at low risk of carrying a fetus with chromosomal anomaly according to nuchal translucency screening. Ultrasound in Obstetrics and Gynecology, 30(5), pp.728-736.​