Figure - PMC

Skip to main content

An official website of the United States government

Here's how you know

Here's how you know

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.

View full-text article in PMC

. 2019 Aug 2;4(4):e001462. doi: 10.1136/bmjgh-2019-001462

Search in PMC
Search in PubMed
View in NLM Catalog
Add to search

© Author(s) (or their employer(s)) 2019. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.

This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.

PMC Copyright notice

Proportion preterm births in 5-year calendar periods from1990 to 2014 and the prevented fractions (PF) related to changes in parity and educational levels across these periods. Figures based on the ORs for parity <3 and education ≥6 years and the change in the prevalence of these characteristics.