Antifertility potentials of metronidazole in male Wistar rats.

There is a growing concern about the decline in the quality of human sperm in recent years. Following reports by previous studies on the toxic effects of metronidazole on testicular functions, this study is designed to investigate further its direct effects on fertility potentials and that of the introduction of vitamin E and testosterone to metronidazole treated rats. A total of 105 adult male and 50 female Wistar rats weighing 170 +/- 10 g (70-90 day old) were used for the experiment. The rats were randomly divided into a control and experimental groups. There were four major groups with 5 subgroups consisting of 5 rats each. Varying doses of metronidazole were used depending on the experiment. Experiment 1; animals were fed with 15 mg kg(-1) of metronidazole, experiment 2, fed with 30 mg kg(-1) of metronidazole, experiment 3, administered with 200 mg kg(-1) of metronidazole and experiment 4, fed with 400 mg kg(-1) of metronidazole. Each experimental group has 5 sub-groups. A: control, B: group fed with the experimental dose, C: experimental dose with vitamin E, D: experimental dose with testosterone, E: fed with experimental dose, vitamin E and testosterone and sub-group F, a reversal group which was left for 8 weeks after cessation of treatment. Parameters assessed were sperm count/motility, hormonal assay, Fertility test for control and treated rats were also carried out. Results showed that metronidazole at the therapeutic dose of 15 mg kg(-1) did not have significant negative effect on the parameters assessed. At the dose of 200 and 400 mg kg(-1), there was reduction in testosterone and follicle stimulating hormone while on the other hand, luteinizing hormone was increased mostly with 400 mg kg(-1) of metronidazole treatment. Body weight was also found to be significantly reduced in rats treated with 200 and 400 mg kg(-1) of metronidazole. The results of this study indicate that metronidazole administration (200 or 400 mg kg(-1)), for 8 weeks, caused a harmful effect on fertility potentials in male rats.