Table 4 Commercial products of IUD [92,93,94]

CuT380A

Copper ion Cu²⁺ release

① Nonhormonal, and effective emergency contraceptives

② Increased incidence of bleeding and cramping

0–0.8

Viracept

Cu²⁺ release

① Lower total copper loading

② Great performance on flexibility

0–0.45

IUB

Cu²⁺ release

① Shape memorized alloy

② Potential risk of expulsions and removals

0–0.29

Mirena

Liletta

Skyla

Hormonal delivery

① Skyla with the lower LNG reduces pain bleeding

0–0.14

GyneFix 200

Frameless IUD

The flexible shape reduces pain and ectopic pregnancy

1.3