• intrauterine devices
• long-acting progestogens

I want to thank Colin Parker for responding to my recent letter1 on behalf of Durbin plc.2 On first reporting this safety issue to Durbin I was told that the problem of kinking of the inserter tube of the TT380 Slimline IUD had previously been reported. Durbin assured me that this had been addressed and sent me more supposedly modified samples. On examining these I found the introducer tube exactly the same in nature, kinking at the slightest bending if the device and plunger were not firmly applied to each other in the inserter tube. This does not occur with the inserter tubes of either the Mirena or the T-Safe CU 380A QL, which when unloaded can be gently curved through at least a 90° angle without kinking. 

I have now also been sent samples by Durbin of a modified TT380 Slimline device that is licensed in New Zealand and Canada. This new design has a notch in the central plunger in which the device sits until full release. The notch is intended to prevent there being any gap between device and introducer rod, thus preventing kinking of the inserter tube. However in the process of releasing the device with the new system, the plunger protrudes into the uterine cavity and as it is very rigid I feel that there may be a risk for perforation. I have never seen an introducer design for a framed device that allows the plunger to protrude into the uterine cavity beyond the introducer tube.

I do not yet see that the manufacturer of Durbin’s TT380 Slimline has solved the problem I have highlighted, which would be resolved simply if the introducer tube was made with a more flexible material, as with the tubes of the other two proprietary devices mentioned above.

I look forward to any responses from other practitioners who may have experience of the original device or indeed of the new inserter as used outside of the UK.