Objective:To investigate the effects of the aqueous extracts of Irvingia gabonensis(Irvingaceae) seeds on the hormonal parameters of male guinea pigs.Methods:The hormonal effects of Irvingia gabonensis on hormonal parameters of male guinea pigs were investigated and compared with that of proviron using enzyme immuno assay method,which was done by reaction of antibody with serum testosterone and testosterone label,magnetic solid phase separation and colour development step.The phytochemical screening of Irvingia gabonensis seeds was also carried out using standard procedures.Results:The aqueous extract of the Irvingia gabonensis seeds(50-400 mg/kg) caused a statistically significance increase(P<0.05 ANOVA) of testosterone in male guinea pigs,from (2.70±0.26) ng/mL to(3.10±0.42) ng/mL on the 7th day and to(3.30±0.48) ng/mL on the 28th day of the administration of the extracts.The highest increase was(3.30±0.48) ng/mL,being obtained after 28 days of treatment.These effects were similar to that of proviron,which was (2.80±0.28) ng/mL and(3.00±0.41) ng/mL on the 7th and 28th day of treatment respectively. The phytochemical screening of Irvingia gabonensis seeds revealed the presence of flavonoids. tannin,alkaloids,carbohydrate,volatile oils,terpenoids,saponins and cardiac glycosides. Conclusions:This study supports the claims on the use of the seeds of Irvingia gabonensis by traditional medicine practitioners as a fertility agent.However,further studies need to be done to isolate and characterize the active principle(s) responsible for this activity in this plant. Objective: To investigate the effects of the aqueous extracts of Irvingia gabonensis (Irvingaceae) seeds on the hormonal parameters of male guinea pigs.Methods: The hormonal effects of Irvingia gabonensis on hormonal parameters of male guinea pigs were investigated and compared with that of proviron using enzyme immuno assay method, which was done by reaction of antibody with serum testosterone and testosterone label, magnetic solid phase separation and color development step. The phytochemical screening of Irvingia gabonensis seeds was also carried out using standard procedures. Results: The aqueous extract of the Irvingia gabonensis seeds (50-400 mg / kg) caused a statistically significant increase (P <0.05 ANOVA) of testosterone in male guinea pigs, (2.70 ± 0.26) ng / mL to (3.10 ± 0.42) ng / mL on the 7th day and to (3.30 ± 0.48) ng / mL on the 28th day of the administration of the extracts. highest increase was (3.30 ± 0.48) ng / mL, being obtained after 28 days of treatment. These effects were simila The phytochemical screening of Irvingia gabonensis seeds revealed the presence of flavonoids. tannin, which was (2.80 ± 0.28) ng / mL and (3.00 ± 0.41) ng / mL on the 7th and 28th day of treatments respectively. alkaloids, carbohydrate, volatile oils, terpenoids, saponins and cardiac glycosides. Conclusions: This study supports the claims on the use of the seeds of Irvingia gabonensis by traditional Medicine practitioners as a fertility agent. Still, further studies need to be done to isolate and characterize the active principle (s) responsible for this activity in this plant.