1. Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX, USA,
2. Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, TX, USA
3. Department of Pediatric Neonatology, University of Texas Medical Branch, Galveston, TX, USA
4. Department of Obstetrics and Gynecology, Abington Memorial Hospital, Abington, PA, USA