Dioscorea oppositifolia, commonly known as Chinese yam or wild yam, has a long history of use in traditional medicine, particularly in Traditional Chinese Medicine (TCM). In TCM, it is believed to tonify the kidneys and spleen, and is sometimes associated with supporting the female reproductive system. The rationale for its use in supporting the "progesterone body system" stems from historical beliefs that wild yam contains substances that might influence hormone balance, specifically due to its content of diosgenin, a steroidal saponin. Diosgenin has been used industrially as a precursor in the laboratory synthesis of progesterone and other corticosteroids. However, the human body cannot convert diosgenin into progesterone naturally; this conversion requires chemical processes not present in human physiology.

There is little to no direct scientific evidence that Dioscorea oppositifolia increases progesterone levels or provides significant support to the body's progesterone system when consumed as a supplement or food. Most human studies and reviews have found no progesterone-like activity attributable to wild yam extracts. Therefore, its use in this context is justified by tradition rather than scientific validation.

In summary, while Dioscorea oppositifolia has traditional use in supporting female reproductive health, there is no robust scientific evidence that it directly supports progesterone production or function in the human body.