Squaw Vine (Mitchella repens) has a long history of use in North American herbalism, particularly among Indigenous peoples and later among Eclectic physicians in the 19th and early 20th centuries. Traditionally, Squaw Vine was used as a uterine tonic and for a variety of female reproductive issues, including menstrual irregularities and discomfort associated with menstruation. The plant was believed to help "prepare" the uterus for childbirth and reduce symptoms such as cramping or pelvic congestion, which could overlap with symptoms classified as PMS Type S (characterized by swelling, bloating, and fluid retention).

However, there is a lack of scientific studies or clinical trials specifically evaluating Squaw Vine's efficacy or safety for PMS, including PMS Type S. The available evidence is almost entirely anecdotal or based on traditional usage patterns. While some herbalists continue to recommend it based on historical precedent, there is minimal pharmacological data to substantiate its mechanisms of action for fluid retention or other PMS symptoms. As such, its use for PMS Type S is justified by tradition rather than scientific validation, and the strength of evidence is weak.