Introduction: The aqueous extract of Azanza garckeana was recently reported of exhibiting ameliorative and pro-fertility properties however the protective effects on formalin testicular toxicity have not been studied. Objective: This study investigated the protective effect of methanol extract of Azanza garckeana on formalin-induced testicular toxicity. Methods: Forty male albino mice were randomly divided into 8 groups of 5. Animals in the first group (1) served as control and administered normal saline (1 ml/kg) by the oral route daily for 40 days. In similar manner, animal in groups 2 received formalin (10 mg/kg) by the IP route, while animals in groups 3; 4 and 5 concurrently received formalin (10 mg/kg IP) and extract at doses of 125; 250 and 500 mg/kg respectively by the oral route. Mice in groups 6; 7 and 8 received the extract at doses of 125; 250 and 500 mg/kg respectively. Phytochemical analysis was conducted for each constituent using specific methods. Gonadotropin and sperm analysis were carried out using standard methods. Result: Phytochemical screening revealed the presence of various constituents, but notably flavonoids. Induced-toxicity with formalin and concurrent treatment with extract at doses of 250 and 500 mg/kg from day 20 to 40 caused significant body weight increase compared to baseline (p < 0.05). Similarly, treatment with the extract alone at all doses caused significant increase in body weight from day 20 to 40 (p < 0.05). Treatment with the extract at 250 and 500 mg/kg, caused a significant increase in weight of testes and epididymis compared to control and untreated group (p < 0.05).The extract induced significant increase in gonadotropin levels of animals compared to control and the untreated group (p < 0.05).The extract at 125 mg/kg demonstrated the highest fecundity potential, but there was no any consistent relationship between GSI and fecundity. Conclusion: This investigation was able to establish the protective and pro-fertility potentials of methanol extract of Azanza garckeana.
