> The real question is what does the manager do with the data.
Direct-mail (or these days, in-app with notifications) coupons. If you know you'll pay full price at CVS, but it's 30% off at Rite-Aid, you'll go to Rite-Aid and buy other stuff as long as you're making the trip.
I mean, maybe there really are enough women buying last-minute to be able to predict, at least for those women -- and identify who those women are.
If that is your motivation you just blanket send those advertisements all month. Because you want women to think of you when they have need. Some women are stocking up before they have need, and so the coupon when they are having their period is when they won't be buying supplies. Even those who are buying as they have need, if they are out they are buying from the closest store at whatever price, while those who are not in an emergency know where the low prices are (wal-mart or such)
So... the risk to women's safety is that they might end up paying less for hygiene products?
No, the risk to women's safety is that someone the woman doesn't want to know, could find out that they're pregnant. (Or using birth control or whatever)
Someone being an advertiser buying the data?