Materials and Methods: This cross-sectional study was conducted on 212 GDM women who referred to diabetes centers at Razi hospital in Ghaemshahr and Imam Khomeini hospital in Sari in 2019. The women were selected through the convenience sampling method. The data collection tools included Medical-Demographics Information Form and Onyx-Bullen’s Social Capital Questionnaire. Finally, data were analyzed by SPSS (version 25) using descriptive and inferential statistics (multiple regression analysis).

Results: The results of this study showed that the mean (standard deviation, SD) of age for GDM women was 29.28 (±5.75). The majority of women (58%) had an academic education. The mean (SD) of social capital was 96.46 (±21.17). Based on the results, a positive and significant correlation was observed between spouse’s education (lower than high school, P = 0.001 and academic education, P = 0.001), wife’s occupation (employee, P = 0.015), spouse’s occupation (employee, P = 0.027), and fasting blood sugar (FBS) (P = 0.048), as well as a significant negative correlation with 2-hour FBS (P = 0.048), 1-hour postprandial glucose level (P = 0.001), economic status (dissatisfied, P = 0.42), overweight (P = 0.009), and obesity (P = 0.020).

Conclusions: The social capital of GDM women is influenced by various socio-economic factors. According to the findings of this study, women who are economically disadvantaged, overweight, obese, and at high blood sugar levels are at greater risk of rejecting treatment due to low social capital, resulting in poor blood sugar control. Therefore, interventions related to promoting social capital in these groups should be pursued more vigorously, and strengthening of social capital and its influencing factors should be considered as one of the main approaches of health promotion.