up the duff
Pregnant. Primarily heard in UK, Ireland. You two have only been married for a couple of months, I can't believe you're up the duff already! I was pretty wild during my university years, which is how I found myself up the duff at 22.
up the duff
pregnant. British informal 1994 Daily Telegraph At 19, he was married (‘only because she was up the duff’ he explains gallantly).