Mobile-based Obstetric Monitoring for Pregnancies Complicated by Hypertension and/or Diabetes (MOM-HD)

Inclusion Criteria: * Pregnant women receiving antenatal care at RCT site * Diagnosed with one of the following: * Chronic hypertension (sustained systolic BP ≥140 mm Hg and/or diastolic BP ≥90 mm Hg, or on antihypertensive treatment before 20 weeks of gestation) * Gestational hypertension or preeclampsia without severe features (sustained systolic BP ≥140 mm Hg and/or diastolic BP ≥90 mm Hg after 20 weeks of gestation) * Gestational diabetes * Age 18 years or older * Access to a smartphone * Gestational age ≤ 34 weeks at enrollment * Able to read and write Exclusion Criteria: * Multifetal pregnancies * Apparent communication difficulties (e.g., hearing, speech, or cognitive impairments), as judged by research assistants * Unable to understand the Nepali language * Severe maternal illness or any condition that precludes active study participation (e.g., preeclampsia with severe features, eclampsia, HELLP syndrome, or other conditions requiring inpatient management) * Declines to provide informed consent