Television viewing: moderator or mediator of an adolescent physical activity intervention?
Consistent with displacement theory, adolescents who watched more TV prior to the intervention showed postintervention increases in vigorous physical activity and concomitant decreases in TV viewing, whereas those who watched less TV showed no change in physical activity or TV viewing.
Elevated progesterone on the day of hCG administration is more likely in women with recurrent IVF failure. Women with two or more IVF failures are twice as likely to have elevated progesterone on the day of hCG administration as women undergoing their first IVF cycle.