I remember when I was in the upper VI a girl I particularly fancied (also 18) was knitting some baby clothes. I enquired, innuendo-laden, as you do, and was told it was her mother, well past 40, that was pregnant. Even though I was a Modern Man before the expression was invented and went all gooey (oo-er missus) it didn't do me any good. I never made any headway with her.