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.
Phillippe M, Ross M, Greene M, Heyl P, Sehgal P.Phillippe M, et al.Am J Obstet Gynecol. 1985 Jul 1;152(5):599-601. doi: 10.1016/0002-9378(85)90635-0.Am J Obstet Gynecol. 1985.PMID: 4014356
Heyl PS, Sappenfield WM, Burch D, Hernandez LE, Kavanaugh VM, Hill WC.Heyl PS, et al.Matern Child Health J. 2013 Sep;17(7):1230-5. doi: 10.1007/s10995-012-1117-5.Matern Child Health J. 2013.PMID: 22907272