[1] Univ Colorado, Div Reprod Sci, Dept Obstet & Gynecol, Anschutz Med Campus, Aurora, CO 80045 USA
[2] Univ Colorado, Sect Neonatol, Dept Pediat, Anschutz Med Campus, Aurora, CO 80045 USA
[3] Res Complex 2,12700 East 19th Ave,Room 3100A, Aurora, CO 80045 USA
[4] Res Complex 2,12700 East 19th Ave,Room 3100C, Aurora, CO 80045 USA