Effects of intermittent 0.5% nitrous oxide/air (v/v) on the fertility of male rats and the post-natal growth of their offspring.

In a study of male rat fertility male Wistar albino rats were exposed to 0.5% nitrous oxide/air mixtures (v/v) for 30 days and control rats were exposed to oil-free air for the same time period. Thereafter each male was mated with three nulliparous female rats and mated again with three more nulliparous rats after a 6-month recovery period. The offspring were weighed and measured for 8 weeks postnatally. There was a significant reduction in mean litter size of the female rats mated with the male rats directly after the nitrous oxide exposure period. The offspring from the female rats mated with the males directly after the exposure period were significantly smaller in size than the control group. These results show a reversible reduction in male Wistar rat fertility, after exposure to 0.5% nitrous oxide in air (v/v), as well as a postnatal growth depression.