Cytotoxicity and teratogenicity of chlorhexidine diacetate released from hollow nylon fibres

Intra-uterine contraceptive devices are associated with an increased incide nce of pelvic infections, possible due to the introduction of vaginal bacte ria into the uterus at insertion. One potential means to overcome this prob lem is the use of a device which releases the antimicrobial agent chlorhexi dine although such an approach carries with it the risk of adverse effects on the endometrium and, possibly, teratogenic effects. Cultured monolayers of endometrial cells were used to assess the cytotoxici ty of both chlorhexidine and chlorhexidine-releasing devices. The results i ndicated that the agent is toxic at concentrations of 1 mu g mL(-1) and tha t the devices potentiated the toxicity. When the devices were tested in a g uinea-pig model, endometrial damage was seen only at the high dose of chlor hexidine, suggesting that there is greater distribution of chlorhexidine in -vivo. Assessment of the teratogenic effects of chlorhexidine in rat embryo nic limb bud tissue cells in-vitro showed that the foetal cells were highly susceptible to the toxic effects of chlorhexidine, but that there was no e vidence of teratogenicity. Overall, the findings suggest that chlorhexidine-releasing devices may be a safe means of reducing infections related to intra-uterine devices, but th at the chlorhexidine may have a toxic effect on foetal cells.