A Mobile Application for Early Detection and Symptoms Trajectories of Postpartum Depression Using Ecological Momentary Assessment (EMA)

This study is developing and testing a smartphone app to detect postpartum depression (PPD) early by collecting brief mood and wellbeing check-ins from pregnant women throughout the day. The goal is to catch warning signs before or shortly after childbirth so women can get help sooner. **You may be eligible if...** - You are pregnant and in your first or second trimester - You are 18 years old or older - You can read and understand Chinese - You own a smartphone with iOS or Android **You may NOT be eligible if...** - You have been diagnosed with a psychiatric condition such as schizophrenia, intellectual disability, or a mood disorder - You have a brain-related health condition such as epilepsy, prior stroke, or a brain tumor - You have a learning disability Talk to your doctor to see if this trial is right for you.