Reversible antifertility effect of aqueous leaf extract of Allamanda cathartica L. in male laboratory mice

The efficacy of oral administration of aqueous leaf extract of Allamanda cathartica (150 mg kg⁻¹ body weight day⁻¹ for 14, 28 and 42 days) in inducing infertility and changes in various male reproductive endpoints was evaluated in Parkes strain mice. The effect of the treatment on organ weight, histopathology, sperm parameters, testosterone level, haematology, serum biochemistry and on fertility indices was assessed. Histologically, testes in extract-treated mice showed nonuniform degenerative changes in the seminiferous tubules as both affected and normal tubules were observed in the same sections. The treatment also had adverse effects on motility, viability, morphology and on number of spermatozoa in the cauda epididymidis. Serum levels of testosterone, alanine aminotransferase, aspartate aminotransferase and creatinine, haematological parameters and liver and kidney histoarchitecture were, however, not affected by the treatment. Fertility of the extract-treated males was also suppressed, although the libido remained unaffected. By 56 days of treatment withdrawal, however, the above parameters recovered to control levels. Our results thus suggest that A. cathartica treatment causes reversible suppression of fertility in male mice, without causing detectable toxic effects.