Data set used in the analysis.

Pregnancy is a period of great transition in women, marked by various physiological, emotional, and social adjustment that can increase a woman’s vulnerability to psychological distress during this critical period. Despite its potential impact on maternal and fetal health, maternal psychological distress remains underexplored in Tanzania, with limited published data on its burden. This study aimed to assess the prevalence and associated factors of maternal psychological distress among pregnant women receiving antenatal care at the Muhimbili National Hospital in Dar-es-Salaam. A hospital-based cross-sectional study was conducted with 287 pregnant women attending antenatal care (ANC) at Muhimbili National Hospital. A probability sampling method was used to select study participants via a simple random sampling technique through a lottery method. The Oslo Social Support Scale (OSSS-3) was employed to assess perceived social support, while the WHO Multi-Country Study on Women’s Health and Domestic Violence against Women tool was used to measure intimate partner violence (IPV). Maternal psychological distress was assessed using the Kessler Psychological Distress Scale (K10). Data were analyzed using Poisson regression with robust variance to estimate crude and adjusted prevalence ratios to determine factors associated with maternal psychological distress, with statistical significance set at p