According to the FDA:
"The U.S. Food and Drug Administration (FDA) recommends that parents and caregivers do not use infant head shaping pillows intended to change an infant’s head shape or symmetry or claim to prevent or treat any medical condition. The FDA is not aware of any demonstrated benefit with the use of infant head shaping pillows for any medical purpose. The use of head shaping pillows can create an unsafe sleep environment for infants and may contribute to the risk of suffocation and death.
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