To assess nutrition-related knowledge, attitudes and practices among pregnant women, and identify socioeconomic and healthcare determinants.

A cross-sectional study on maternal nutrition during pregnancy.

Pregnant women attending primary healthcare centres in the south of Tehran from December 2022 to March 2024.

1535 pregnant women of all ages living in the south of Tehran (both Iranian and non-Iranian).

Pregnant women were systematically selected from primary healthcare centres. Data were collected via validated questionnaires and electronic health records. Statistical analyses included multivariate logistic regression (adjusted ORs (aORs) with 95% CIs) and generalised linear mixed models.

The findings revealed that a majority of pregnant women (83.3%; 95% CI 81.2% to 85.3%) exhibited low levels of nutritional knowledge (scores below 12), whereas 14% demonstrated moderate knowledge (scores between 12 and 17), and only 2.7% (95% CI 1.9% to 3.8%) possessed high nutritional knowledge (scores above 18). In terms of attitudes, 36.9% of respondents expressed positive views toward nutrition, with higher education significantly associated with positive attitudes (aOR=1.8; 95% CI 1.3 to 2.5, comparing higher vs lower education levels). Dietary variety was consistently reported by 65.4% of participants, while 8.5% lacked dietary variety. Statistically significant associations were observed between educational attainment, socioeconomic status and nutrition-related practices (p

As a cross-sectional study, these findings highlight substantial gaps in nutrition knowledge among pregnant women in Tehran, with socioeconomic status and education playing crucial roles in shaping dietary behaviours. Improving nutritional education through healthcare interventions is essential for enhancing maternal and fetal health outcomes.