Evaluation of an e-health integrated intervention for pregnant women with co-occurring mental health and substance use symptoms: an exploratory randomized clinical trial

Background: The co-occurrence of substance use and mental health problems in pregnant women implies higher maternal-foetal morbidity, and treatments often do not meet care needs. This study aims to generate preliminary evidence and hypothesis by exploring the potential effect of an integrated intervention based on third-generation therapies by comparing a telephone intervention with a digital intervention and treatment as usual. Methods: In an exploratory randomised trial, 111 pregnant women (out of 2014 screened) with co-occurring mental health and substance use symptoms were assigned to either telephone-delivered intervention, digitally-delivered intervention, or treatment as usual groups. Interventions, based on third-generation therapy, lasted eight weeks. Outcomes (alcohol, tobacco use, depression, anxiety, and trauma) were measured at baseline and after two, four, eight, and twelve months. Results: The telephone intervention group performed significantly better with regard to alcohol, depression, and trauma symptoms after two and four months compared to the digital intervention and treatment as usual groups. The digital intervention group showed limited benefit and higher attrition. All groups had returned to baseline by the 12 month point. Conclusions: Standardised clinical interventions delivered by telephone can improve the treatment outcomes of pregnant women with co-occurring mental health and substance use problems. New approaches are needed to effectively implement these interventions via digital support. Trial registration: ClinicalTrials.gov ID NCT06965270 (retrospectively registered in May 11, 2025).