Background & Objective: Obsessive-compulsive disorder is a common disease in psychiatry which increases anxiety in approximately 2% of the world population. Recent reports suggest that OCD starts in menstruation, Pregnancy, post-partum periods which causes failure in women's quality of life. The aim of study was to determine the onset of (OCD) in fertile women.

 Methods: In a descriptive study in 2006, 53 women with DSM-IV were interviewed for obsessive disorder at psychiatry clinic of Fatemi hospital. A questionnaire including two parts on demographic information and 8 questions on the onset of obsessive disorder in menstruation, pregnancy, puerperium periods was completed. Data were analyzed through SPSS.

 Results: In 3.8%, the onset of obsessive disorder was with the first menstruation period. In 12.5% it was during pregnancy. In 57.1% (4) of obsessive samples onset of obsessive was in second pregnancy. In 16.24% onset of OCD was after delivery. In 28.8% it was after first delivery and 30% after first delivery had affective disorders.

 Conclusion: The menstruation, pregnancy, post partum may be a periods of risk for recurrence or onset of obsessive compulsive disorder and women should be taken care of more in order to avoid disorders like depression. Midwife clinicians caring for women need to be aware of the impact of these symptoms and attention for mental health in women.