Figure 2.
The number of included studies on the birth prevalence of CHD in five-year bands from 1970 to June 2017. Year-bands are defined according to the publication time of included studies.
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.