Evidence-based in vivo tocolytic activities of Alchornea laxiflora (Benth) (Euphorbiaceae) in female rats

Abstract

Background and objectives: The leaves of Alchornea laxiflora are used in herbal medicine as a remedy for threatened abortion. This study was designed to scientifically evaluate the tocolytic effect of the aqueous and methanolic extracts of Alchornea laxiflora leaves on implantation and last term of pregnancy in rats.

Methods: For the implantation test, spermpositive females were orally given either distilled water (10 ml/kg), salbutamol (0.2 mg/kg), aqueous or methanolic extract (55 and 100 mg/kg) of Alchornea laxiflora from day 1 to day 7 of pregnancy. For the late pregnancy study, some gestational parameters (duration of pregnancy, number and weight of pups at birth) were measured after treating pregnant females, as in the implantation test, from day 17 to day 25.

Results: For the implantation test, all sperm-positive females showed implantation sites and, the duration of gestation, the resorption rate, the litter size and the weight of pups at birth were unaffected at delivery compared to control. For the last term pregnancy, Alchornea laxiflora extracts also expressed a tocolytic activity ranking from 28.57% (aqueous extract, 100 mg/kg) to 71.4% (methanolic extract, 55 mg/kg). No significant differences were observed regarding the mean litter size and the variation in body weight between the treatment groups. Salbutamol produced similar effects.

Conclusion: Treatment of females at late gestation stage with plant extracts and salbutamol extended the expected delivery period. These results support the tocolytic traditional claim regarding Alchornea laxiflora.

Keywords: Alchornea laxiflora, implantation, parturition, tocolysis, rat