A peanut ball is an hourglass-shaped inflatable device used during labor to assist in opening the pelvis and encouraging the baby’s descent. Unlike the traditional round birthing ball, this specialized tool is primarily designed for use while the birthing person is resting or confined to bed, often due to an epidural or fatigue. By stabilizing the legs and maintaining an open-legged position, the peanut ball helps mimic the pelvic-opening benefits of squatting or movement. This can potentially shorten the duration of labor and reduce the rate of cesarean delivery. The correct size is determined by its height, which is measured from the floor to the top of the ball’s lobe when laid on its side.
Determining the Correct Size
The primary factor for selecting the appropriate peanut ball size is the height of the birthing person, which ensures that the hips and knees are positioned correctly to maximize pelvic space. Peanut balls are available in sizes measured by their height in centimeters, with the most common being 40 cm, 50 cm, and 60 cm. Using a ball that is too large can lead to hip discomfort, while one that is too small will not effectively open the pelvis.
For individuals who are petite, measuring under 5 feet 3 inches tall, the 40 cm peanut ball is recommended. The 50 cm size is appropriate for those with an average height, specifically between 5 feet 3 inches and 5 feet 6 inches. Birthing individuals who are 5 feet 7 inches or taller require the 60 cm ball to achieve the necessary leg separation and alignment.
The goal of proper sizing is to ensure that when the ball is placed between the legs, the knees are positioned either level with the hips or slightly higher. This alignment helps to create an asymmetrical position in the pelvis, which encourages the widening of the pelvic inlet or outlet. A birthing person may use different sizes throughout labor, as the best fit can change depending on the specific position being utilized.
Proper Techniques for Use During Labor
The peanut ball is most often used in side-lying positions, which are effective for facilitating fetal rotation and descent, especially when an epidural limits mobility. In the standard side-lying position, the ball is placed between the knees and thighs, with the legs slightly bent, which opens the top of the pelvis (the inlet). Changing sides frequently, every 30 to 60 minutes, is recommended to promote progress and encourage the baby to navigate the curves of the pelvis.
A variation called the semi-sitting lunge involves the birthing person in a semi-reclined position with the head of the bed elevated. In this technique, one leg is draped over the ball’s center, creating an asymmetrical opening in the mid-pelvis, while the other leg remains bent to the side. The “peanut hug” is another option where the ball is placed between the thighs while side-lying, and the birthing person wraps their arms around the ball, mimicking a squatting posture. These positions use the ball to stabilize the legs and maintain a wide-legged stance.
Safety and Inflation Guidelines
Peanut balls should be constructed from anti-burst material to ensure they can withstand the weight and pressure applied during labor. Before use, the ball should be inflated until it is firm, but still yields slightly to pressure, rather than being rock-hard. Proper inflation is necessary for the ball to maintain the correct height and provide stable support for the legs and hips.
Because the peanut ball is primarily used by those who are confined to bed or have reduced sensation from an epidural, assistance is always required for positioning and repositioning. A labor partner, nurse, or doula should be present to help move the birthing person and the ball to prevent accidental falls or injury. Frequent position changes are encouraged, but these movements must be performed safely with support, especially when alternating sides to promote symmetry in the labor process.