I have found that it is often helpful for mums to understand how their body might change during their pregnancy.  There are many changes that will occur in the mother’s body to allow her developing baby to grow, and these changes affect how the mother moves her body during her pregnancy.

The first trimester runs from the time of conception to 12 weeks gestation (or 14 weeks from the last menstrual period).  During the first trimester is when the mother might begin to have morning sickness, feel more tired, need to urinate more often, and notice her breasts feel tender.  These changes occur because of the growth and development that is happening for the mother and her baby.  The developing baby (or foetus) is most at risk to damage from alcohol, drugs, medications and illness in the first trimester.

Postural Changes

In terms of changes to posture and the spine there is usually a posterior (toward the back) rotation of the pelvis as a result of the internal re-arrangement of the organs within the pelvis and abdomen (tummy).  The reason for the increased need to urinate is that the weight of the uterus (womb) rests on the bladder and pelvic floor muscles.  As the uterus grows bigger it tends to push upwards against the small and large intestines, before starting to push forwards resulting in the appearance of a pregnant belly or ‘baby bump’.

This backward rotation of the pelvis can put some strain on the hip flexor muscles, the back muscles and the abdominal muscles and may cause some soreness or pain in these areas as the mothers body adjusts to this new distribution of weight. 

Respiratory Changes

The respiratory diaphragm (the muscle that sits under your ribs and helps you to breathe) is pushed about 4 cm upwards early in pregnancy  and the lower ribs expand outwards, to keep the amout of space in the chest for breathing about the same.  As the internal organs are pushed upwards to make room for the growing uterus, the respiratory diaphragm has more pressure on it and this can lead to some increased tightness or pain in the middle of the back.

Breast Changes

There is a lot of development occurring within the mother’s breasts during the first half of pregnancy to get them ready to produce milk.  The increased weight of the breast tissue can pull the upper part of the back forwards and the curve in the lower neck can increase to help accomodate the change in the postural centre of gravity.  This can lead to tightness around the base of the neck and the upper ribs.

Decreased Energy Levels

For the mother, there is often an increased desire to sleep or take a nap during the first trimester as her body puts a lot of energy into the changes taking place due to her pregnancy.

By the end of the first trimester the baby will be about 7.5 – 10 cm long and will weigh between 0.5 – 28 grams.

Finding Relief

If you are feeling pain or discomfort during your pregnancy, osteopathic treatment may be of benefit.  Osteopathic treatment is gentle and safe throughout pregnancy, and may help to enhance the body’s ability to accomodate the changes that are occurring in the musculoskeletal system.

You may also be intereted in “Body changes during the 2nd Trimester of pregnancy”. or "Body Changes during the 3rd Trimester of Pregnancy"

This articles was written by Dr. Alison Neilson B.App.Sc. (Comp.Med.), M.Ost. of Renew Osteopathy, Mornington

If you are interested to learn more about Osteopathy read Alison's article in our Practitioner Profile section - Osteopathy

References

Stone C. Visceral and Obstetric Osteopathy. Philadelphia: Churchill Livingstone, Elsevier, 2007. Ch 10.

Bullock JE, Jull GA, Bullock MI. The Relationship of Low Back Pain to Postural Changes During Pregnancy. The Australian Journal of Physiotherapy. 1987;33(1):10-17.

Moore K, Dumas GA, Reid JG. Postural changes associated with pregnancy and their relationship with low-back pain. Clinical Biomechanics 1990;3:169-174.