Okay, the user wants me to translate "fluid retention" into Traditional Chinese. Let me check the rules again. The first rule says to translate all content into Traditional Chinese. The second rule states that if the content is already in Traditional Chinese, leave it as is. The third rule is to provide only the translation without any explanations.
So, "fluid retention" is an English term. I need to make sure I translate it correctly. The direct translation would be "體液滯留" or "水腫". Wait, "fluid retention" is commonly known as "水腫" in medical terms. But maybe "體液滯留" is more literal. However, in Traditional Chinese medical terminology, "水腫" is the standard term for edema, which is caused by fluid retention. So I should use "水腫" here. Let me confirm. Yes, "水腫" is the correct term. The user might be looking for the medical term, so I'll go with "水腫".