Here are some statistics about births in the United States, from the U.S. Census Bureau:
4.3 million: Number of births in the United States in 2006. Of this number, 435,427 were to teens 15 to 19, and 112,432 to mothers 40 or older.
25.2: Average age of women in 2005 when they gave birth for the first time. This is up 3.8 years since 1970.
40 percent: The percentage of births that were the mother's first in 2006. An additional 32 percent were the second-born; 17 percent, third; and 11 percent, fourth or more.
37,402: Number of births in 2005 that did not occur in hospitals.
1 in 31: The likelihood of a woman delivering twins in 2005. Her chances of delivering triplets and higher order multiple births was approximately 1 in 618.
August: The month with the highest number of births, with 369,316 taking place that month in 2005.
Tuesday: The day of the week with the highest number of births, with an average of 13,169 taking place on Tuesdays during 2005.
2.1: The total fertility rate (TFR) in 2006 – the first time since 1971 that the nation's TFR was at replacement level, which is the birth rate required to replace the population.
