The proposed study is a randomized controlled trial to examine the efficacy and safety of active acupuncture versus placebo acupuncture for the treatment of postpartum depression. The investigators hypothesis is that active acupuncture would be superior to placebo acupuncture in the short-term treatment of postpartum depression.

This study will be a randomized, controlled, subject- and assessor-blind trial in patients with postpartum depression. Eligible subjects will be randomly assigned to active acupuncture or placebo acupuncture. The subjects will receive acupuncture treatment twice per week for 4 consecutive weeks. The acupuncturist of this trial will not participate in data collection and data entry. The trial assessor will be blind to the subjects' treatment allocation.

Inclusion Criteria:

• Ethnic Hong Kong Chinese aged 18 years or above;
• Within 6 months of giving birth;
• Edinburgh Postnatal Depression Scale (EPDS) (Cox et al., 1987) score higher than or equal to 12 or being diagnosed as depressed by their obstetrician;
• Meeting the Diagnostic and Statistical Manual of Mental Disorders-IV diagnosis criteria for major depressive disorder;
• 17-item Hamilton Depression Rating Scale (HDRS17) (Hamilton, 1960) score of between 12 and 19 at screening and baseline assessment;
• Willingness to give informed consent and comply with trial protocol.

Exclusion Criteria:

• Suffering from other psychiatric disorders such as schizophrenia, other psychotic disorders, bipolar disorder or substance use disorder;
• Serious physical illnesses or mental disorders due to a general medical condition which are judged by the investigator to render unsafe;
• A significant risk of suicide according to the rating of HDRS17 item 3 (score higher than 2), i.e., presence of ideas or gesture of suicide;
• A presence of idea of self-harming according to the rating of EPDS item 10 (score higher than 0);
• A significant risk of infanticide according to the investigator assessment;
• Any acupuncture treatment during the previous 12 months prior to baseline;
• Valvular heart defects, bleeding disorders or taking anticoagulant drugs;
• Infection or abscess close to the site of selected acupoints;
• Herbal remedies or psychotropic drugs that are intended for depression are taken within the last 2 weeks prior to baseline or during the study.
• Receiving counseling or psychological therapies at baseline or during the study;
• Participation in any clinical trial within the previous 3 months prior to baseline;