We get that too- i'm not pregnant, but I find a couple of people pick up second hand clothing from charity stores for our kids sometimes, and alot of people have been passing on their old things to us lately too- we have two girls, and so many clothes it's absurd.
My second daughter has more than enough with her big sister's hand-me-downs as it is.
We just tend to pass them straight back to goodwill or whatever, do a big clear out of clothes and toys every so often.
I always try not to seem ungrateful when we get stuff like that, but I can't help being a little annoyed- I always feel that those clothes and things should be available in the charity stores for poeple who need them- who can't afford to keep their kids in new clothes.
I don't like to think that there may be babies or children going without just because people we know love a bargain.
'specially in the wintertime.
Maybe if you explain it that way? Say your really grateful to be thought of, but it's making you feel guilty when there are people in real need of affordable childrens clothing?