This study will investigate the effectivenss of bright light therapy(10000 lux white)on pregnant women with major depression disorder.

Depression during pregnancy is a common and high impact disease.Children who are exposed to maternal depression during pregnancy have a higher risk of adverse birth outcomes, such as low birth weight, and more often show cognitive, emotional and behavioral problems.Therefore, early detection and prompt treatment of depression during pregnancy can benefit both mother and child.However, the window of opportunity in pregnancy is small and from the perspective of the child postponement is in fact non-treatment. Psychotherapy might take a long time to be effective and do not work for all people. Further, the safety of pharmacological treatment for pregnant women with depression is still a big concern .Psychiatric medication use for depression in pregnancy may also pose a risk of fetal growth retardation and preterm delivery, as well as withdrawal symptoms in the new born. Therefore, investigating non-pharmacological approaches to treating depression during pregnancy is urgent and relevant, for both mother and child. Preliminary evidence shows that bright light therapy (BLT) is an effective treatment for pregnant women with depression based on several theoretical and clinical considerations, with effect size around 0.45 and without adverse effects to the new born. In this study we aim to investigate the effectiveness of BLT on pregnant women with major depression.

Inclusion Criteria:

Women; 18~45 years of age; medically healthy, with normal ocular function; 13~28 weeks pregnancy; DSM-V diagnosis of major depressive disorder HAMD score ≥18

Exclusion Criteria:

DSM-V defined bipolar disorder、schizophrenia、schizoaffective disorder,anxiety disorders; substance Use Disorders; substance use within the last 6 months; suicidal ideation, suicidal attempt, suicide behavior, and attempted suicide; being treated by the light therapy; with antidepressant in recent 2 months; Multiple pregnancy; Any obstetrical care or medications for physical disorders that might confound treatment results; current use of β-adrenergic blockers, melatonin, or St. John's wort; thyroid function test results inconsistent with normal pregnancy