Figure 2.
Histograms of birth weight (grams) by reported gestational age for US birth data from the years 2001 to 2008: (a) 24, (b) 26, (c) 28, and (d) 30 weeks.
Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.