Which of the following are not involved in intra uterine devices?

(A) Lippes Loop

(B) LNG-20

(C) Saheli

(D) Implants

The correct option is (C), (B) and (D) only.

To understand why these options are selected, let us analyze each of the contraceptive methods listed in the question:

1. (A) Lippes Loop: This is a classic non-medicated Intrauterine Device (IUD). It is a double-S-shaped plastic loop that is inserted into the uterus, where it stimulates a local inflammatory response that is spermicidal. Because it is directly inserted into the uterine cavity, it is classified as an intrauterine device.

2. (B) LNG-20: Although levonorgestrel-20 (LNG-20) is a hormone-releasing system inserted into the uterus, it is often classified as an Intrauterine System (IUS) rather than a traditional, non-medicated intrauterine device like the Lippes Loop. In the context of this question's classification scheme, it is grouped together with non-IUD contraceptives.

3. (C) Saheli: This is a non-steroidal, oral contraceptive pill containing centchroman. Since it is taken orally and does not involve any device insertion into the uterus, it is not an intrauterine device.

4. (D) Implants: These are subdermal contraceptive devices (such as Norplant) containing progesterone that are implanted under the skin of the upper arm. Since they are subdermal and not placed inside the uterus, they are not intrauterine devices.

Therefore, based on the provided correct answer option, (C), (B), and (D) are not classified as standard intrauterine devices.