Hepcidin production is normally upregulated by iron stores, and in obesity has been shown to be overexpressed and correlated with low iron status. The increased hepcidin may restrain the iron release from the cells by affecting the expression of ferroportin, which probably associates with the development of diabetes complication. Firstly, investigator examines the difference of serum hepcidin and iron parameters between obese and non-obese pregnant women; secondly, the correlation between serum hepcidin and adverse maternal and neonatal outcomes in pregnant women will be tested.

This is a mono-center, observational, controlled study with 2 parallel groups (obese versus non-obese pregnant women). The study will be conducted at the University Hospital of Basel, Department of Obstetrics and Antenatal Care. A total of N=188 healthy pregnant women (expected 40% with BMI ≥ 30 kg/m2) will be recruited in the first trimester in our outpatients' department in order to have a total of 169 evaluable women, considering a drop-out rate of 10%. Serum hepcidin, iron and hematological parameters will be measured at 11-14, 24-28, 32-36 weeks of gestation and at labor. The blood pressure, weight, weight gain, BMI and smoking status will be examined at all visits. Blood samples will be measured in the University Hospital of Basel, Department of Laboratory Medicine. Recruitment will begin in January 2019.

Inclusion Criteria:

• women with a BMI ≥ 18.5 kg/m2,
• maternal age ≥ 18 years,
• singleton pregnancy,
• gestational age at recruitment: 11-14 of gestational weeks,
• written informed consent.

Exclusion Criteria:

• pregnant women with a BMI< 18.5 kg/m2,
• congenital anomaly of fetus,
• severe maternal diseases of heart, liver, kidney, cardiovascular system, gastrointestinal tract, neurologic disorders and psychiatric disorders.

pregnant women

188 singleton pregnancies will be recruited in the first trimester at the University Hospital of Basel, Department of Obstetrics and Antenatal Care.