For people with osteoporosis: Anastrozole lowers the Clomid levels in your body, which may cause your bones to become weak or thin. This could worsen your osteoporosis and further increase your risk for fractures. Your doctor will check your bone mineral density before starting and during treatment with this drug. For people Clomifene Citrate cycle length high cholesterol: This medication may increase your cholesterol levels. This can raise your risk of serious heart problems. For people with heart disease: If you have a history of blockage in your heart arteries, anastrozole may cause low blood flow to your heart.