What the Bible says about Significance of Number Twelve
(From Forerunner Commentary)
The healing of a woman with a flow of blood is found in three of the gospels (Matthew 9:20-22; Mark 5:25-34; Luke 8:43-48), a miracle sandwiched between two halves of another miracle, the resurrection of the daughter of Jairus, a ruler of the synagogue. What makes the woman's healing unique is that it was performed without a word being spoken beforehand.
As it interrupted the raising of Jairus' daughter, the woman's healing was probably a test of patience for Jairus. More positively, the interruption had the potential to encourage him, helping to build the faith he had already exhibited, especially since his daughter had become much worse in the meantime. Indeed, she had died.
These two miracles are linked, not only in their parallel occurrence, but also by the number twelve, often used in the Bible to connote government. Jairus' daughter was twelve years old (Mark 5:42), and the bleeding woman had been sick for twelve years (Mark 5:25). However, both needed Christ to heal them. It does not matter how long one has been alive, salvation is always through Christ (Acts 4:10-12). Both the bleeding woman and the girl were about to see God's perfect government at work.
Martin G. Collins
The Miracles of Jesus Christ: Healing a Woman With a Flow of Blood