I have been washing sheets a lot... Pregnancy leads to eating in bed and then I get crumbs and need to wash!
i make my bed any time I fold clothes. I always fold on my bed so I like to have a nice smooth workspace. So it depends on how often I get around to folding clothes!
We don't use top sheets. Only fitted and a duvet - so it just gets pulled up. Twice/week when my cleaning lady comes and does it And sheets get washed once/week when my cleaning lady does it. My house was a wreck at the beginning of the pregnancy when I was too sick to do anything - and DH was at his wits end trying to clean up and take care of DD and work - so we got more help! She's a godsend!