While the groom built their new home, the bride also made preparations, including the embroidery of the swaddling bands with which the couple’s hands would be wrapped under the wedding canopy. Later these bands would also be used to secure blankets or swaddling clothes around the couple’s infant children. The symbols on the bands often indicated family history.11 Mary was from the tribe of Judah, so she may have used symbols common to that lineage such as a lion, a lamb, or a tree of life. As a descendant of David, she was also entitled to use the royal colors of blue and white. The symbolic significance of swaddling bands was so important that the embroidery on each side of the swaddling bands had to match exactly, with “right” and “wrong” sides indistinguishable. This symbolized the complete harmony of inner and outward life.12
I found this at: http://www.lds.org/pa/display/0,17884,7244-1,00.html. I liked the connection between the wedding covenants and the birth of the child.
"Ye shall find the babe wrapped in swaddling clothes. . ."