Kim,

Sounds like these people are showing their own opinions of what they would do, by commenting on your situation! Hopefully they are doing it without meaning to!
Being 37 weeks I'm a bit snappy and would come back at them.... 'Wont be much of an age gap' - good thing it's not your baby then!
Try not to let them worry you too much! As long as you and DH are happy then that's all that matters!

xxoxo