Table 3.

Psychological factors related to preterm delivery in studies from 2000 to 2010

Author, Year, (Reference No.)	Study type	n	Risk Factor
Jandaghi et al., 2011	Cross-Sectional	10913	Stress•
Ganji et al., 2009	Descriptive	1237	Stress #
Âbdollahy and Mohamadpor, 2004	Descriptive	1200	Types of pregnancy (wanted or unwanted) #
sehati shafaie et al., 2010	Descriptive	960	Stress #
			Types of pregnancy (wanted or unwanted •
Nasiri et al., 2009	Cohort	682	Anxiety•
Lotf Alizadeh et al., 2005	Case-Control	600	Stress•
Khalaji Nia and Sadeghi Moghaddam, 2011	Cross-Sectional	400	Stress•
			Types of pregnancy (wanted or unwanted)•
			Social support#
Kamali Fard M, 2010	Case-Control	396	Social support•
Ardekani and Salari, 2005	Case-Control	385	Stress•
Dabbaghi et al., 2001	Descriptive	360	Anxiety•
			Stress•
Shah Hosseini et al., 2008	Cohort	282	Anxiety•
Alipour et al., 2011	Cohort	156	Anxiety#

^•A significant relationship between this variable and preterm delivery was found in this investigations

^#No significant relationship between this variable and preterm delivery was found in this investigations