mHealth Intervention to Prevent Postpartum Depression and Anxiety in Chilean Women (WWWT)

The goal of this clinical trial is to evaluate the effectiveness of a digital psychoeducational intervention, "What Were We Thinking" (WWWT), to prevent the development of postpartum depression and anxiety symptoms in first-time mothers in Chile. The study includes adult women with a healthy, full-term infant younger than two months who are receiving care in primary health centers. The main questions it aims to answer are: * Does participation in the WWWT intervention reduce depressive and anxiety symptoms at 3 months after the end of the intervention compared to usual care? * Does participation in the intervention improve maternal self-efficacy, perceived social support, and coparenting relationship quality compared to usual care? Researchers will compare an experimental group receiving the full WWWT intervention with a control group receiving usual care to determine the effectiveness of the intervention. Participants will: * Complete self-report questionnaires assessing depressive symptoms, anxiety symptoms, maternal self-efficacy, perceived social support, and coparenting at baseline and at 3-month follow-up * Be randomly assigned to either the intervention group or the control group * Receive the WWWT intervention between 4 and 10 weeks postpartum (intervention group), including: * Fourteen psychoeducational video modules (3-5 minutes each) delivered via text messaging over 4-5 weeks * Individual contact with a trained facilitator through text messaging * One virtual group session with other mothers and a facilitator * Continue receiving usual care in primary health services (control group) and receive a shortened version of the intervention after the follow-up assessment