Obesity has reached epidemic proportions in our patients who are of childbearing age, with pregnant patients of normal weight being in the minority. The pregnancy-related complications attributable to obesity affect not only the pregnant women, but also her fetus and potentially both mother and child for their lifetimes. Pregnancy is associated with altered immunity. The physiologic state of chronic inflammation in obesity affects systemic immunity and metabolism, and may be associated with several of the complications associated with maternal obesity. The interplay between pregnancy, obesity and inflammation may have far-reaching implications for fertility, pregnancy, the fetus and neonate.