Background: Perinatal mood and anxiety disorders (PMAD) cause substantial morbidity and mortality globally. Kenya, like many low- and middle-income countries, experiences severe shortage of specialized mental healthcare workers and poor coverage of screening and management for PMAD. Provision of screening and treatment by lay and non-specialist providers in the context of routine maternal child health services may enhance access to mental health services and improve outcomes.   Methods and analysis: In a hybrid type II cluster randomized clinical trial in 20 facilities in Western Kenya , we will evaluate the clinical, service delivery, and implementation outcomes of a stepped-care model integrating: 1) screening of all pregnant women for depression and anxiety symptoms, 2) Problem Management Plus (PM+) counseling delivered by trained lay providers, and 3) telepsychiatry for women with severe symptoms, suicidality, or inadequate response to PM+. The intervention package also includes a bundle of implementation strategies such as audit and feedback, process mapping, health educational health talks, and procurement of antidepressants for all sites. In addition, intervention sites will receive provider training, structured supervision and financial compensation for providers.   Facilities will be randomized 1:1 to intervention and enhanced standard of care (basic screening and referral to specialist care), using restricted randomization. We will enroll a total of 2,970 women. Women will be eligible if they are pregnant and ≥20 weeks' gestation, attending antenatal care at the facility, ≥14 years old, and screen positive for PMAD symptoms (Patient Health Questionnaire [PHQ]-2≥3 and/or Generalized Anxiety Disorder-[GAD]-2≥3). Assessments will be conducted at enrollment (pregnancy), 6 weeks, 14 weeks, and 6 months postpartum among participants in both study arms to align with routine well-baby visits.   Primary outcomes are PMAD symptoms (PHQ-9 and GAD-7 score) change at 14 weeks postpartum using an intent-to-treat analysis. Secondary outcomes include quality of life at 14 weeks postpartum, PM+ mechanism of action, and adverse pregnancy outcomes at 6 weeks postpartum. Using mixed methods, we will evaluate acceptability and fidelity of the intervention and compare service delivery and other implementation outcomes (penetration, efficiency, equity, cost) across arms and alongside multilevel drivers of implementation success.

The authors have declared no competing interest.

Registry: ClinicalTrials.gov Trial number: NCT06456307 Trial URL: https://clinicaltrials.gov/study/NCT06456307

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

The study protocol was reviewed and approved by the Kenyatta National Hospital–University of Nairobi Ethics and Research Committee (KNH-UoN ERC) (approval number: P425/04/2023) and the University of Washington Institutional Review Board (UW IRB) (approval number: STUDY00017933). Written informed consent will be obtained from all participants prior to study participation.

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