Background: The offspring of obese women are at increased risk for systemic inflammation. Blood concentrations of inflammatory proteins in preterm newborns of obese women have not been reported.

Aim: To compare blood concentrations in the highest quartile for gestational age of inflammatory proteins and day of blood specimen collection on two days at least one week apart of newborns of overweight (i.e., BMI 25-29) and obese women (i.e., BMI ≥ 30) with newborns of women with lower BMIs. Because deliveries for spontaneous indications are more likely than those for other indications to be associated with inflammation, we evaluated spontaneous indication deliveries separately from maternal or fetal indications.

Study design: Prospective cohort study.

Subjects and outcome measures: We measured from 939 children born before the 28th week of gestation 25 inflammation-related proteins in blood obtained on postnatal day 1 (range 1-3), day 7 (range 5-8) and day 14 (range 12-15).

Results: Among infants delivered for spontaneous indications, maternal BMI was not related to elevated concentrations of any protein. Among infants delivered for maternal (i.e., preeclampsia) or fetal indications, those whose mother was overweight or obese were more likely than others to have elevated concentrations of inflammation proteins.

Conclusions: Maternal pre-pregnancy overweight and obesity appear to contribute to a pro-inflammatory state in very preterm newborns delivered for maternal or fetal indications. Our failure to see a similar pattern among newborns delivered for spontaneous indications, which often have inflammatory characteristics, might reflect competing risks.