An Investigation into the Use of an Herbal Labor Induction Tincture Containing Black Cohosh, Cramp Bark, Partridgeberry, and Motherwort on Contractile Responses Produced from Isolated Strips of Mouse Uterine Tissues

Introduction: Alternative solutions in the form of herbal remedies meant to ease or expedite the process of labor have often been pursued and administered but have seldom been quantitatively tested for efficacy. Published research has shown some validation for some commonly used herbs such as blue cohosh (Caulophyllum thalictroides), red raspberry (Rubus idaeus), castor bean (Ricinus communis) and evening primrose (Oenothera biennis) on isolated mouse uterine strips. Methods: This study tested an array of herbs used by midwives in a labor induction tincture, which included black cohosh (Actaea racemosa), cramp bark (Viburnum opulus), partridgeberry (Mitchella repens), and motherwort (Leonurus cardiaca). Each of these four herbs were prepared as aqueous extracts and applied individually to uterine tissues in an organ bath apparatus. Results: Results and analyses indicated that all treatment tissues produced significant increases in contractile forces when compared to their own endogenous motilities (p<0.0001). These responses, however, were not significantly different among the four herbal treatments, but were comparable to those produced by 10-5 M oxytocin. Conclusions: This study provides empirical support for the use of these plants as herbal uterotonics, and it is plausible that these results, collected in vitro, may support the use of such a tincture to enhance or augment labor in vivo. Consideration of the active constituents found in each herbal, their concentrations, solubilities, cell signalling pathways, and the potential to interact in a synergistic or attenuating manner would be beneficial prior to recommending a given herbal for use at an organismal level.