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.
aConditional regression model adjusted by: maternal age, maternal and paternal occupation, and maternal intake of coffee.
bp for trend=0.03
CI = confidence interval
