I agree. Although I've gotten quite a few comments like that. I generally respond with a witty comeback. Like if someone says, "Haven't you heard of birth control?" I answer--"Oh yeah--are you looking for a recommendation? With your demeanor I would NOT suggest having children." Accompanied by a deer in the head lights look with a sweet smile leaving them to wonder if I really had just said that! If I'm in a good mood and depending on which children I have with me. . . my older ones do NOT need to know all about various forms of bc at this point I might say something like. "Why yes and you should definitely not use what we used. It toally didn't work."
Or "Yes, but my dh just can't keep his hands off me. Don't you wish yours was the same way?" Or I could go on. I just don't tolerate that kind of comment from people.