T-shaped IUDs with a copper surface area of 380 mm2 and copper bands on the transverse arms are the most effective types of copper-containing IUDs.

This study was done to determine discontinuation rates and reasons for discontinuation at 1 year of the small-sized Mini TT380 Slimline IUD compared with the standard-sized TT380 Slimline.

Clinical records were available for 67 women fitted with a mini IUD and 63 women fitted with a standard IUD. At 1 year, twice as many standard IUD users had discontinued their IUD use compared with mini IUD users. Complaints of pain and bleeding were more than double in those women who discontinued standard IUD use compared with those who discontinued using the mini IUD. These differences were statistically significant and were unrelated to parity.

The study concluded through its findings that more women using a standard-sized ‘gold standard’ IUD rather than its smaller counterpart complained of pain and bleeding, leading to higher discontinuation at 1 year. More research on the association between size and discontinuation of these IUDs is needed.

Reference: https://srh.bmj.com/content/45/4/263