Summer Babies Poor Test Scores???

A recent article says that depending on when your baby is conceived affects how smart they are. Something about summer time creating more exposure to pesticides/chemicals in the mom-to-be's food/water. All I can tell you is that my oldest child was conceived in June and she is off the charts gifted with a tested IQ above 150. Does this mean she would be higher if conceived in lets say January? I don't know - but I think they tested people in Indiana ;)