The safest contraception is the barrier method i.e. male partner should use condoms. All methods involving female partners have side effects, some of which can be quite serious. Copper T is relatively safer than consuming hormonal agents by mouth though less safe, and more complicated, than condoms for males.
Intra-Uterine System Mirena involves the use of a drug-eluting (a hormone called progesterone) T-shaped device. It is not only expensive (about Rs. 8000) but has many side effects some of which are: irregular bleeding, absence of periods, inflammation of the abdominal organs (Pelvic Inflammatory Disease), ovarian cysts, ectopic pregnancy (can be quite a problem), perforation of the intestines, high blood pressure, depression, weight gain, diabetes, loss of sexual urge, etc.
It is risky to depend upon information on drugs and devices obtained through commercial web sites.