How do I get off mailing lists for products, thanks to Motherhood Maternity?
I'm not sure, but often if you just cross through it and write "rts" on the envelope in big black letters, then stick it in a postbox, they will take you off their list. This is possible in the UK, I'm not sure if it will be possible where you live.
Alternatively, if you're in the UK, you can go to the mailing preference site.
All of these offers must have an address on them somewhere, surely? It might be a lot of looking, but when you find it, write to them, enclosing the label off the front (which has code numbers and your address on), saying you want to come off the mailing list. Or go into Motherhood Maternity and ask the staff how to get off the list.