Birthing ball

A Birthing Ball or Labor Ball is a large air–filled rubber ball (about {convert|60|cm} in diameter) that a woman can sit on during labor. A birthing ball allows the woman to rock back and forth seated on a softer surface. A woman on a birthing ball may need a support person to keep her steady. A birthing ball may be especially useful during back
Found on http://en.wikipedia.org/wiki/Birthing_ball

Birthing Ball

A rubber ball that is approximately 25 inches in diameter and filled with air. The laboring woman can sit on the ball during labor to helpo with the pain of contractions, back labor and other discomforts. The woman is able to rock back and forth on the ball during labor and often the change in position encourages the baby to drop further into the..
Found on http://www.pregnology.com/AZ/B/3

Birthing ball

A large air-filled rubber ball that a woman can sit on during labor. It allows the woman to rock back and forth during labor and may help reduce back discomfort during contractions
Found on http://www.whattoexpect.com/pregnancy/glossary/b.aspx
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