Question

why don't copper t prevent STDs​

Answer 1

Copper Ts don't prevent STDs because they don't create a barrier or a covering and therefore diseases can still be transmitted.

Answer 2

The Copper T is a simple intra-uterine device (IUD) made of a flexible, "T" shaped piece of plastic wrapped with a thin copper containing wire. It is a contraceptive device which prevents from getting pregnant. Copper ions prevent pregnancy by inhibiting the movement of sperm as they are toxic to sperm. Other than this copper T cannot inhibit the action or kill bacteria or viruses which cause different STDs.