I never heard anything like that. If you believe in Guadalupe (and according to what I am told, 100 per cent of Mexico does), then she is a "heavenly lady". This is her "miraculous appearance" clothing -- somethings maybe the angels made for earth. It is not of the earth, but it is a woven type cloth, and earthly like images on it, but very finely done.
Does your mother dress as nicely as the Virgin of Guadalupe and show as good a taste? Hopefully so.
Now that I look at the image, it appears that the stars are arranged in a grid-like pattern, and not randomly as they would appear in the sky.
Also, I wondered how you can tell that she is pregnant, since there doesn't appear to be any form to her garments.