Fascinating article in the New York Times. The age at which a woman has her first baby has dramatic ramifications.

First-time mothers are older in big cities and on the coasts, and younger in rural areas and in the Great Plains and the South. In New York and San Francisco, their average age is 31 and 32. In Todd County, S.D., and Zapata County, Tex., it’s half a generation earlier, at 20 and 21, according to the analysis, which was of all birth certificates in the United States since 1985 and nearly all for the five years prior.

Many graphs in this article. Well worth a review.