Failure rate of copper T is very minimal as it is one of the most effectrive non hormonal
intra uterine contraceptive
device (IUCD). Failure rate is only around 2% after one year of use. Also it is the only type of long acting reversible contraceptive effective up to 10 -12 years.
.Although it can result in heavy bleeding, & though spotting between the first few periods is not uncommon it very rarely results in absence of menstural cycles.
Delay could be due to two reasons. Either the copper T has slipped & not in the same position or it is expelled (pushed) outside. If it is expelled then there is no protection against pregnancy
. Painful & heavy unusual vaginal discharge
So first check if the strings of copper T are in its original place. If it is not in its place, then the chances of pregnancy is more.