Nope, it's fine without any punctuation. If you read old books, you'll see it with a dieresis mark (like a German umlaut) over one of the os.
Yes, it should be hyphenated.
Yes it should be hyphenated.
Yes it should be hyphenated.
yes check-up should be hyphenated
It should be hyphenated.
Yes it should be hyphenated.
"Field" is not hyphenated.
Yes it should be hyphenated.
Yes it should be hyphenated.
No it shouldn't be hyphenated.
Self-made should be hyphenated.
No it shouldn't be hyphenated. It is one word.