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.
Yi HJ, Kim JH, Koo HS, Bae JY, Cha SW, Yang KM.Yi HJ, et al. Among authors: koo hs.Obstet Gynecol Sci. 2014 May;57(3):208-15. doi: 10.5468/ogs.2014.57.3.208. Epub 2014 May 15.Obstet Gynecol Sci. 2014.PMID: 24883292Free PMC article.
Koo HS, Cha SH, Kim HO, Song IO, Min EG, Yang KM, Park CW.Koo HS, et al.Clin Exp Reprod Med. 2015 Dec;42(4):149-55. doi: 10.5653/cerm.2015.42.4.149. Epub 2015 Dec 31.Clin Exp Reprod Med. 2015.PMID: 26816874Free PMC article.
Yi HJ, Koo HS, Cha SH, Kim HO, Park CW, Song IO.Yi HJ, et al. Among authors: koo hs.Clin Exp Reprod Med. 2016 Jun;43(2):133-8. doi: 10.5653/cerm.2016.43.2.133. Epub 2016 Jun 23.Clin Exp Reprod Med. 2016.PMID: 27358833Free PMC article.
Koo HS, Park CW, Cha SH, Yang KM.Koo HS, et al.J Ultrasound Med. 2018 Apr;37(4):851-857. doi: 10.1002/jum.14418. Epub 2017 Oct 9.J Ultrasound Med. 2018.PMID: 28990204
Chung K, Cho HY, Kim YR, Jhung K, Koo HS, Park JY.Chung K, et al. Among authors: koo hs.J Med Internet Res. 2020 Mar 4;22(3):e14095. doi: 10.2196/14095.J Med Internet Res. 2020.PMID: 32130139Free PMC article.
Koo HS, Bae JY, Kang IS, Koong MK, Kim HO, Cha SH, Choi MH, Kim JY, Yang KM.Koo HS, et al.Clin Exp Reprod Med. 2011 Jun;38(2):109-14. doi: 10.5653/cerm.2011.38.2.109. Epub 2011 Jun 30.Clin Exp Reprod Med. 2011.PMID: 22384428Free PMC article.