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.
Chung TK, Cheung LP, Lau WC, Haines CJ, Chang AM.Chung TK, et al. Among authors: chang am.Aust N Z J Obstet Gynaecol. 1994 Aug;34(4):432-6. doi: 10.1111/j.1479-828x.1994.tb01264.x.Aust N Z J Obstet Gynaecol. 1994.PMID: 7848234Clinical Trial.