[1] Univ Oklahoma, Hlth Sci Ctr, Obstet & Gynecol, Oklahoma City, OK USA
[2] Univ N Carolina, Urol, Chapel Hill, NC USA
[3] Upstate Univ Hosp, Syracuse, NY USA
[4] Univ Oklahoma, Hlth Sci Ctr, Coll Publ Hlth, Oklahoma City, OK USA
[5] OUHSC, Ob Gyn, Oklahoma City, OK USA
[6] NICHD, NIH, Rockville, MD USA