I had my baby at 40 weeks 2 days. I think some ladies have children early but some have them really late. A good friend of the family always had her babies past 40 weeks but this is normal for her and she never goes for induction and lets nature takes it's cause, all 4 babys 40+ weeks all normal deliveries too.
Like everything else we are all different and although 40weeks is considered the 'normal' there are always those who are going to have them early and those that are late and that's normal too.