['The objective of this study was to compare umbilical cord plasma leptin between infants of mothers who experienced preeclampsia and infants of control subjects and to study the relation between cord plasma leptin and infant obesity, as indicated by ponderal index.', 'On the basis of a population of approximately 13,000 deliveries, we compared cord plasma leptin from preeclamptic (n = 256 women) and control pregnancies (n = 607 women) after taking the differences in gestational age and ponderal index into account.', 'Cord plasma leptin increased strongly with gestational age, both in the preeclampsia group and the control subjects (P <.01), but at each gestational age the preeclampsia group had higher leptin levels than control subjects (P <.01). Adjustment for the higher ponderal index among control subjects (P <.05) did not alter the difference in leptin levels between the groups.'] Is umbilical cord plasma leptin increased in preeclampsia?