Postpartum depression is more intense and intrusive: Women may lose interest in life, withdraw from family and friends, or think about harming themselves or their children.

CNN: Postpartum depression: When moms feel out of control

Some have suggested he may have suffered from bipolar disorder, experiencing frequent mood shifts from intense bursts of impulsive activity to paralysing depression.

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Bipolar leads to intense mood swings, which can last months, ranging from depression and despair to manic feelings of joy, overactivity and loss of inhibitions.

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In retrospect, Loo believes she experienced postpartum depression with each of her three children, but the most intense feelings of losing control came with her youngest.

CNN: Postpartum depression: When moms feel out of control

Almost any parent will agree that the indescribable joys can be matched by equally intense feelings of worry, doubt, helplessness, anxiety, and, of course, depression.

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