What is already known about the subject?
·         GDF15 is linked to obesity and diabetes and improves beta cell function.
·         Pregnancy is a natural state of insulin resistance and increased beta cell function.
·         Circulating GDF15 is high during pregnancy, but has not been studied during pregnancy in women with obesity.
What are the new findings?
·         GDF15 increased more during pregnancy in women of normal-weight than in women with obesity.
·         High GDF15 levels in pregnancy associated with low fat-free mass, with higher pregnancy-associated nausea and with carrying a female fetus.
·         High increases in GDF15 associated with increased beta-cell function and decreased blood glucose late in pregnancy.
How might the results change the direction of research or the focus of clinical practice?
·         Our research supports the recent interest in therapeutic potential of GDF15 or GDF15 agonists in the area of obesity and insulin resistance.