[1] Univ Michigan, Dept Urol, Ann Arbor, MI 48109 USA
[2] Arbor Res Collaborat Hlth, Ann Arbor, MI USA
[3] Duke Univ, Med Ctr, Dept Obstet & Gynecol, Durham, NC 27710 USA
[4] Univ Washington, Dept Urol, Seattle, WA 98195 USA
[5] NIDDK, Bethesda, MD 20892 USA