Squawvine has a few different name one being partridge berry vine.
According to a study aty the NIH.gov
Mitchella repens contains resin, wax, dextrin, saponins, alkaloids, glycosides, and tannins . Mitchella repens herb was already used by Indians in North America to prevent miscarriage, pregnancy complications, and to reduce pain in labor .Mitchella repens herb has sedative  and diuretic  effects. Extracts of Mitchella repens herb are typically used in the puerperium to alleviate nipple swelling and pain, and in the burn of the breasts [23,29]. It was stated in  that there are no literature reports about safety of use of Mitchella repens herb in pregnant women and during lactation.