About one third of all women of reproductive age in the US are obese (body mass index [BMI] 30). Recent studies show that children born to mothers who were obese while pregnant may have lower cognitive performance and higher risk of developing neurodevelopmental conditions. The goal of this study is to see 1) if there are negative effects of maternal obesity during pregnancy on newborn's brain development; 2) if these effects on brain development persist to age 1 & 2 years, and if there are changes in neurodevelopmental outcomes associated with maternal obesity; and 3) if inflammation in pregnant women associated with maternal obesity is one of the main reasons for the brain changes in offspring. The investigators will recruit pregnant women from early pregnancy who are either obese or normal weight and are otherwise healthy. The Investigators will measure their weight, body fat percentage, blood inflammation markers, family environment, what the participants normally eat, how much physical activity the participants usually have, and other characteristics during pregnancy. When their babies are born, the investigators will evaluate the brain development of their babies use magnetic resonance imaging (during natural sleep) at age two weeks and again at age 1&2 years. The investigators will also measure the neurodevelopmental outcomes at age 2 years. Then compare the findings to see if there are group differences in these measures between babies born to normal-weight and obese mothers, if other parameters measured at pregnancy also play a role, and if inflammation markers during pregnancy strongly correlate with infant brain development and neurodevelopmental outcomes.