Antifertility activity of Thevetia peruviana (Pers.) K. Schum leaf in female Sprague-Dawley rat

OBJECTIVES: Thevetia peruviana (Pers.) K. Schum. (Apocynaceae) is known to possess cardioactive glycoside such as thevetin A, thevetin B, neriifolin, peruvoside, thevetoxin, and ruvoside. Traditionally, T. peruviana leaves are used as abortifacient. The aim of the present study is to evaluate antifertility potential of T. peruviana leaves. SUBJECTS AND METHODS: Cardiac glycoside freed leaves of T. peruviana were extracted with methanol using maceration method. The dried cardiac glycoside-free methanolic extract of T. peruviana leaves (TPL-Me-G) was screened for phytoconstituents and evaluated for its effect on estrogen-primed female Sprague-Dawley rat uterus model. It was further studied for effects on the estrous cycle, implantation, and effect on estrogen and progesterone. STATISTICAL ANALYSIS USED: Statistical analysis was done by ANOVA followed by Dunnett's t-test. RESULTS: Alkaloids, flavonoids, essential oils, carbohydrates, and amino acids were found to be present in the glycoside-free extract. Thin-layer chromatography (TLC) in n-butanol: acetone: water (4:1:5) revealed the presence of quercetin and kaempferol. The presence of flavonoids (quercetin 0.0326% and kaempferol 0.138% on dry weight basis) was reconfirmed by high-performance TLC analysis. The extract was able to induce uterine contractions (EC(50), 0.170 mg/ml) in a dose-dependent manner. Further investigation showed significant (P < 0.001) extension of estrous cycle and anti-implantation activity of the extract by reduction of the progesterone level. CONCLUSIONS: Methanolic extract of T. peruviana leaves (TPL-Me-G) containing quercetin 0.0326% and kaempferol 0.138% possesses a significant (P < 0.001) antifertility potential by virtue of decreasing the progesterone level.