The effects of commercial preparations of red raspberry leaf on the contractility of the rat's uterus in vitro

Reprod Sci. 2010 May;17(5):494-501. doi: 10.1177/1933719109359703. Epub 2010 Mar 10.


We investigated the direct effects of various commercially available preparations of red raspberry leaf (RRL) on the in vitro contractility of uteri collected from diethylstilbestrol (DES)-treated nonpregnant (NP) and late pregnant rats. In DES-treated NP rats, RRL tea and capsule caused weak contractions. Neither preparation affected the ability of oxytocin to initiate contractions; however, both partially inhibited preexisting oxytocin-driven contractions at the highest concentration tested. Red raspberry leaf ethanol extract had little effect on contractility. Pretreatment with tea did not alter the ability of oxytocin to initiate contractions. In pregnant animals red raspberry leaf tea had variable effects on preexisting oxytocin-induced contractions, sometimes augmenting oxytocin's effect and sometimes causing augmentation followed by inhibition. We conclude that the biological activity of RRL varies depending on the herbal preparation used and pregnancy status. These results do not support the hypothesis that RRL augments labor by a direct effect on uterine contractility.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dose-Response Relationship, Drug
  • Female
  • Fruit*
  • Plant Extracts / pharmacology*
  • Plant Leaves*
  • Pregnancy
  • Rats
  • Rats, Wistar
  • Uterine Contraction / drug effects*
  • Uterine Contraction / physiology*
  • Uterus / drug effects
  • Uterus / physiology


  • Plant Extracts