Second-trimester sonographic comparison of the lower uterine segment in pregnant women with and without a previous cesarean delivery.

Objective: To compare measurements of the lower uterine segment during a second-trimester sonographic examination in women with and without a previous cesarean delivery.

Methods: Women undergoing second-trimester sonographic examination, 24 with a history of cesarean delivery and 30 control subjects with no history of cesarean delivery, were recruited for transvaginal sonographic evaluation of the lower uterine segment with a high-frequency probe. The uterine niche or previous cesarean scar site was defined as a small triangular anechoic defect in the anterior wall of the uterus.

Behavioral effects of chronic exposure to low levels of lead in Drosophila melanogaster.

Through human activity lead has become a serious environmental neurotoxin, known to affect activity levels, attention and both sensory and cognitive function in children. Study of lead would be facilitated by having a model system that could be manipulated easily and quickly. We find Drosophila melanogaster ideal as such, and we have been studying effects of lead on courtship, fecundity and locomotor activity.