How to Deal With Problems With Gifts

Dear Sage Bridger and Wise Disobedient Guest, is this a British person? We don't know. My husband and I are expecting our first baby in a couple of months. How can I politely steer people to gifting me things I actually need rather than stuff that the baby might use once before they grow out of it,. without sounding ungrateful? Cheers, and that's Jo.