Objective: Our aim was to determine how Ramadan fasting effects serum Human NAD-dependent deacetylase sirtuin 1 (SIRT1/SIR2L1) and visfatin levels during pregnancy. Materials and methods: Thirty-six patients were included in this case-control study. The patient group consisted of 18 pregnant women who were Ramadan fasting. Another healthy 18 pregnant women with matching pregnancy weeks and ages formed the control group. Blood samples were obtained from the patients for biochemical analyses and serum adipokine level measurements. Results: The mean sirtuin and visfatin levels in fasting pregnant women were 2.87 +/- 0.95 and 60.18 +/- 19.49 ng/mL, respectively, while the mean serum sirtuin and visfatin levels in the control group was determined to be 4.28 +/- 1.45 and 23.26 +/- 6.18 ng/mL, respectively. A statistically significant difference was determined between the groups (p = 0.002, p = 0.0001). A correlation analysis provided a negative correlation between number of fasting days and sirtuin levels (r = 0.45, p = 0.005) and a positive correlation with visfatin levels (r = 0.73, p = 0.0001). Conclusion: As a result, while the serum sirtuin 1 level of pregnant women decreased due to fasting in Ramadan, we determined that their visfatin levels increased and this increase was in correlation with the days of fasting.