I once got -er -trapped during a fire drill. My then girlfriend's room was part of the fire escape route in a whole block of female physiotherapists at a certain hospital and while she could leap out and retreat in a dressing gown I had to stay peering embarrassedly out of the sheets until I could retrieve my trousers to get out of bed.   I also once locked myself out of a hotel room in no nightclothes but luckily found a large towel in an unlocked bathroom!

At home I wear what I please since my dog is not easily embarrassed, and keep a huge dressing gown in case people stop over without pleasurable intent.

I have never worn a woman's nightgown, but I don't understand why women often wear nighties rather than pyjamas if they are going to wear nightwear - unless for titillation.