Does Seasonale birth control pill act as an abortifacient like other pills?

The director of education at the Crisis Pregnancy Center I volunteer at was recently somewhere listening to a Pro-Life contraceptive expert who was telling them about Seasonale, a new birth control pill that supposedly doesn't change the lining of a woman's uterus. I asked my OB's nurse about it and go the impression that it works no differently than the current BC pills, only you have a period 4x a year. I was wondering if you have done any research on this Pill, and if so, what have you found about it? Is it an abortifacient? Or is it safe?