- Aims: Resistin, a newly discovered adipokine, is thought to play a key role in the regulation of insulin resistance. The objectives of this study were to develop a nomogram of maternal plasma concentrations of resistin from 11 weeks of gestation to term and to determine whether resistin concentrations differ between normal and overweight pregnant women. Methods: In this cross-sectional study, plasma concentrations of resistin were determined in normal pregnant women of normal body mass index (BMI 18.5-24.9; n=261), overweight pregnant women (BMI ≥25; n=140), and non-pregnant women of normal BMI (n=40). Blood samples were collected once from each woman between the first trimester and term. Percentiles for resistin concentration were determined for five prespecified windows of gestational age. Plasma resistin concentration was determined by immunoassay. Non-parametric statistics were used for analysis. Results: The median maternal plasma concentration of resistin between 11 to 14 weeks of gestation in women of normal weight was significantly higher than non-pregnant women; the plasma concentration of resistin increased with gestational age. Conclusions: Normal pregnant women have a higher median plasma concentration of resistin than non-pregnant women and the concentration of this adipokine increases with advancing gestation. Alterations in the maternal plasma concentration of resistin during pregnancy could contribute to metabolic changes of pregnancy.