Evaluation of inhalational anaesthetics on murine in vitro fertilization

Chronic exposure to inhalational anaesthetics has been implicated in producing adverse reproductive effects in exposed personnel. A longer duration of general anaesthesia during laparoscopic oocyte retrieval for human in vitro fertilization programmes was associated with a decrease in fertilization and cleavage rates. In this study, a mouse model was used to evaluate the effects of clinical concentrations of nitrous oxide, isoflurane and halothane on in vitro fertilization. Mouse oocytes were exposed to 3 inhalational anaesthetic mixtures, oxygen/nitrous oxide, oxygen/nitrous/isoflurane 0.5% or oxygen/nitrous oxide/halothane 0.5% just prior to insemination and their subsequent development was assessed. The fertilization (2-cell) rate and early embryonic growth rate, i.e., 4-cell and morula rates were not statistically different from those of controls which were exposed to air. This study showed that short exposures to clinical concentrations of nitrous oxide, isoflurane and halothane had no deleterious effect on in vitro fertilization and early embryonic growth up to the morula stage in the mouse. Their effects on subsequent implantation and foetal teratogenecity are unknown.