An official website of the United States government
The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before
sharing sensitive information, make sure you’re on a federal
government site.
The site is secure.
The https:// ensures that you are connecting to the
official website and that any information you provide is encrypted
and transmitted securely.
Singh KA, Huston-Presley LP, Mencin P, Thomas A, Amini SB, Catalano PM.Singh KA, et al. Among authors: amini sb.Obstet Gynecol. 2010 May;115(5):998-1002. doi: 10.1097/AOG.0b013e3181da901a.Obstet Gynecol. 2010.PMID: 20410774Free PMC article.