One of the most common complaints of pregnancy is an aching back. Your growing baby pulls your abdomen forward, and unless you work at keeping your stomach tucked in to the extent you can, you're likely to end up with swayback. This unnatural curve of a swayback pulls your spine out of line and strains the muscles in your back; they respond with painful spasms.

A good backrub is welcome anytime, but particularly when pregnancy makes your back hurt. If the pain is severe or persistant, talk to your doctor or midwife about it. In the meantime, lie on your side on a bed, exercise mat, or thickly carpeted floor (use pillows to maintain your positions), or sit on a stool, leaning forward on a table if necessary, while a friend or relative follows these steps:

Lightly stroke the back on either side of (but never on) the spine, working from the shoulders down to the hips and back to the shoulders.
With your thumbs on either side of the base of the neck, stroke outward and back along the shoulders.
Stroke down one side of the back using deep pressure with the palm of one hand, followed by a light storke with the fingers of the other hand. Glide your hands upward and repeat on the other side of the back, ending at the buttocks.
Rotating your thumbs on either side of the spine, move your hands up the back from the buttocks to the shoulders, then let your hands glide down to the buttocks.
Knead the buttocks between your fingers and thumb.
End by repeating step one in the reverse direction.

It helps to keep a constant, soothing rhythm and to keep at least one hand in contact with the back at all times. Use fine powder or slightly warmed oil, cream, rubbing alcohol, or witch hazel to help the hands slide on the skin. Stop part or all of the massage if it hurts.

Childbirth Magazine'sHow to Give (and Get) a Great Back Rub

Childbirth Magazine's
How to Give (and Get) a Great Back Rub