Svetlana V Doubova*, Patricia Espinosa-Alarcón, Sergio Flores-Hernández, Claudia Infante and Ricardo Pérez-Cuevas
* Corresponding author: Svetlana V Doubova svetlana.doubova@imss.gob.mx
BMC Women's Health 2011, 11:6 doi:10.1186/1472-6874-11-6
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