Prenatal exposure to DTT may contribute to the obesity epidemic in women, U.S. researchers suggest. Researchers at the University of South Carolina, Nationwide Children"s Hospital, Ohio State University and Michigan State University looked at daughters ages 20-50 of 259 mothers who had eaten fish caught in Lake Michigan during pregnancy. The expectant mothers were exposed to polychlorinated biphenyls, or PCBs, and DDE as a result of eating the lake fish from 1973-1991. DDE is a long-lived metabolite of the insecticide DDT -- banned in many countries -- than can bioaccumulate in marine life such as sports-caught fish. The mothers had been included in previous studies and several blood samples had been taken. The researchers controlled for maternal height and body mass index and number of pregnancies, and for daughters" age, birth, weight, and whether they had been breastfed. The study, published in the journal Occupational and Environmental Medicine, finds a statistically significant association with prenatal DDE levels and increased body fat. PCBs did not seem to affect weight, the study says. "Prenatal exposure to the estrogenic endocrine-disrupting chemical DDE may contribute to the obesity epidemic in women," the study authors say in a statement quoted by the United Press International (UPI).