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.
Flowchart of participants selection, Nurses’ Health Study II (NHSII), 1989–2011. Of the 116,429 participants at baseline in 1989, a total of 106,256 were included in the analytic sample followed up to 2011 for incident early natural menopause (n = 2,754).
