Sciatica occurs in 30% of pregnant women and is characterized by sharp pains in the hip and buttock on one or both sides, shooting down the back of the thigh. There may also be numbness of the anterior thigh on the effected side.

The sciatic nerve (tibial and common peroneal nerve bound together) arises from nerve roots exiting the spine between L4 and S3. Any compression of these nerve roots can lead to these symptoms.

Sciatica can occur at any time, but pregnancy predisposes towards it:

1. Pregnancy causes an accentuated lordosis of the spine.

2. Pregnancy causes weight gain

3. Pregnancy softens the cartilage of the sacro-iliac joint, de-stabilizing the pelvic architecture and increasing the likelihood of stretching or compression of the nerves within the pelvis.

Treatment of sciatica:

• Avoid standing for long periods of time.

• When sleeping, assume a semi-fetal position, with both knees drawn up and a pillow placed between the knees.

• When sitting, make sure the knees are slightly flexed so that the knees are at least level with the hips or slightly higher than the hips.

Sleeping with one leg straight and the other knee drawn up is a bad position as far as the back is concerned. Torsion is placed on the lower spine, aggravating any pressure on the sciatic nerve that may be present.

Sleeping on the side while pregnant is a good, idea, but both knees should be drawn up (flexing the thighs). Either side will work well.

In order to maintain this semi-fetal position comfortably, it is necessary to place a small pillow, folded blanket or towel between the patient's knees. This will absorb moisture, separate the legs, minimizing skin-to-skin contact, and provide additional support to the legs. With practice, this position will become very comfortable.

When sitting at a desk, posture is very important.

These pictures illustrates two problems:

• The chair is too high, resulting in her knees being lower than her hips.

• She is not sitting straight toward the desk. This position places torsion on the lower back, aggravating her sciatica problem.

The lower picture has corrected one of the two problems.

• She has lowered her chair and put a Chicago phone book underneath her feet, elevating them. This results in her knees being level with her hips, rocking her pelvis backwards and straightening out the lower spine. This will ease pressure on the sciatic nerve.

• She has not turned to face the desk squarely. That would have solved the second problem.