One of the methods for relieving labor pain is utilization of heat or cold. Results of the present study denoted that hot and ice packs applications could significantly reduce labor pain. Pain relief with ice application could be due to many mechanisms including inhibition of nociceptors, a reduction in muscle spasm and/or a reduction in metabolic enzyme activity level or via the analgesic descending pathway of the central nervous system such asendorphins (
temperature of the skin/soft tissue lead to improve blood flow. The effect of heat on pain is mediated by heat sensitive calcium channels. Heat generates action potentials that increases stimulation of sensory nerves and causes the feeling of heat in the brain. Once calcium channels activated, they can inhibit the activity of pain receptors (Holowatz, etal. 2005).
Grant (1964) advocated massage with ice for the treatment of musculoskeletal pain and named his
technique cryokinetics. Marshall (1971) published a study using ice cube massage for the relief of chronic pain of eye herpes. Melzack (1983; 1980) found that intense sensory input produced by ice massage of the web between the thumb and forefinger resulted in a fifty percent reduction in acute dental pain