True about Spermicidal agents is all of the following, EXCEPT?
**Core Concept**
Spermicidal agents are a class of contraceptive drugs that work by disrupting the sperm cell membrane, ultimately leading to sperm death. They contain nonoxynol-9, a surfactant that causes cell lysis.
**Why the Correct Answer is Right**
The correct answer is related to the mechanism of action of spermicidal agents. Nonoxynol-9 disrupts the sperm cell membrane by inserting itself into the phospholipid bilayer, causing cell lysis and death. This is due to its surfactant properties, which allow it to solubilize and disrupt the cell membrane.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because spermicidal agents are indeed used for contraception and do contain nonoxynol-9.
* **Option B:** This option is incorrect because spermicidal agents do disrupt the sperm cell membrane, causing cell lysis and death.
* **Option C:** This option is incorrect because spermicidal agents do work by causing cell lysis, but it's the mechanism of action that's being questioned.
**Clinical Pearl / High-Yield Fact**
Spermicidal agents are often used in combination with barrier methods, such as condoms, to provide additional protection against pregnancy and STIs.
**Correct Answer: D.**