Main disadvantage of IUD is that

Options

A. The devices are permanently placed in uterus and cannot be removed even if couple want to have children
B. The device has to be inserted by a physician in the uterus through vagina
C. The devices are expelled out without the knowledge of wearers
D. Both a and c

Answer

### Step-by-Step Solution:

1. **Understanding IUD**: Intrauterine devices (IUDs) are contraceptive devices that are inserted into the uterus to prevent unwanted pregnancies. They are effective and widely used for birth control.

2. **Identifying Disadvantages**: The question asks for the main disadvantage of IUDs. We need to consider the potential drawbacks associated with their use.

3. **Permanent Placement**: One of the concerns is that once an IUD is placed, it remains in the uterus until it is removed by a healthcare professional. This can be seen as a disadvantage for couples who may want to conceive but have the device still in place.

4. **Insertion by a Physician**: IUDs must be inserted by a qualified healthcare provider. While this is a necessary procedure, it is not necessarily a disadvantage in the context of the question.

5. **Expulsion of the Device**: A significant disadvantage of IUDs is that they can sometimes be expelled from the uterus without the user's knowledge. This can happen during menstruation or sexual intercourse, and it poses a risk of unintended pregnancy.

6. **Conclusion**: The main disadvantage of IUDs is that they can be expelled from the uterus without the wearer being aware, which can lead to unintended pregnancies.

### Final Answer:
The main disadvantage of IUDs is that they can be expelled from the uterus without the knowledge of the wearer.

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