Comment by prlambert

Yes, it's not about the menstruation, it's about pregnancy. Having a kid, especially the 1st, is the single largest shift in consumer spending in most people's lives (if they have kids). Aside from all the obvious spending on baby stuff, it predicts buying a house and where they might live, and puts that person (new mother, in this case) on a well-modeled path of buying behavior for the next 18 years. Needs and spending as children age through different phases are quite predictable and the spending is huge and touches almost every aspect of the person's life.