Returning to fertility:

For most women, fertility comes back quickly after discontinuing OCs. However, 1 percent to 2 percent experience some delay in the return of normal reproductive cycles. In rare instances, hormones can stay suppressed for months or even years, though for the majority, menstrual cycles normalize within three months. Cycle suppression is more likely to cause infertility in older women, so if having a child is a high priority, you might consider switching to another reliable contraceptive method as you approach 30.