Hello, Emergency pills contain excess doses of hormone and thus disturb the normal hormonal milieu and create irregular menstrual cycles for some period. This includes withdrawal bleed and delay in the normal cycle by a week or two. Expert help should be sought if the normal cycle is not seen even after ten days after it is due. Intake of the pill as she had within the stipulated time provides almost complete protection and therefore, pregnancy is not an issue here. Please remember, use of these pills should be restricted to one or two occasions only per year and instead, some regular form of contraception should be chosen. Hope this helps.