1. Student Research Committee, Mazandaran University of Medical Sciences, Sari, Iran.
2. Department of Reproductive Health and Midwifery, Sexual and Reproductive Health Research Center, Mazandaran University of Medical Sciences, Sari, Iran.
3. Department of Biostatistics, Health Sciences Research Center, Mazandaran University of Medical Sciences, Sari, Iran.
4. Midwifery and Reproductive Health Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.