Ninety female outpatients with obsessive-compulsive disorder (OCD) completed a semistructured interview to assess the relationship between different OCD symptom dimensions and the onset of OCD at menarche or during the perinatal period. Patients with hoarding symptoms had an earlier age at menarche than non-hoarders (12.1 +/- 1.3 vs 13.0 +/- 1.5 years, p = 0.019) and were more likely to report OCD onset at menarche (OR = 4.1, p = 0.034). Patients with symptoms of the contamination/cleaning dimension were more likely to report the onset of their disorder during pregnancy or postpartum (OR = 9.3, p = 0.048).