Which is an incorrect statement with regards to ovarian torsion?

• A. 70% of cases occur in women less than 30 years of age
• B. 20% of cases in women less than 30 are associated with pregnancy
• C. it has an increased incidence in women receiving ovarian stimulation treatment
• D. a tender mass is felt in 10% of cases
• E. when it occurs in post menopausal women, neoplasm should be excluded