You can start from https://en.wikipedia.org/wiki/List_of_U.S._states_and_territories_by_fertility_rate https://en.wikipedia.org/wiki/List_of_U.S._states_and_ter

You can start from https://en.wikipedia.org/wiki/List_of_U.S._states_and_territories_by_fertility_rate https://en.wikipedia.org/wiki/List_of_U.S._states_and_territ... and its list of sources, and drill down from there. Remember to subtract births to recent immigrants from the numerator, and number of recent immigrants from the denominator. It won't take long to verify my claim.