The Blessed Mother is often depicted with twelve stars above her head. Why?
It is a reference to Revelation 12:1-2, in which a pregnant woman who is about to give birth is clothed with the sun, with the moon under her feet, and with a crown of twelve stars on her head. The woman is believed to symbolize the Blessed Mother, among other things, because the child she delivers is “a male child, one who is to rule all the nations with a rod of iron … [and] her child was caught up to God and to his throne” (Rev. 12:5). The stars in the crown may represent either Christ’s twelve apostles or the twelve tribes of Israel.
The Woman of Revelation 12 by Jimmy Akin