1. Department of Obstetrics & Gynecology, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, U.S.A.
2. Division of High-risk Pregnancy, Department of Obstetrics & Gynecology, Mackay Memorial Hospital, Taipei 10449, Taiwan
3. Children's Health Research Institute, University of Western Ontario, London, Ontario N6C 2V5, Canada
4. Department of Pediatrics, University of Colorado, Anschutz Medical Campus, Aurora, CO 80045, U.S.A.
5. Department of Pediatrics and Biochemistry, University of Western Ontario, London, Ontario N6A 5C1, Canada