Part 2: To repair Netzach-Hod-Yesod so that Chessed-Gevurah-Tiferet can be revealed over them requires the entire period of Pregnancy. Just as the thirteen years and one day are explained as the time needed for Chochmah-Binah-Daat to enter over Chessed-Gevurah-Tiferet, similarly the nine months of Pregnancy are the time of preparation for Chessed-Gevurah-Tiferet to enter over Netzach-Hod-Yesod. The two periods do not need to be of equal lengths, because in each case the time involved depends on the needs of the process.
The Idea of Repair Embedded in the Tree of Life
Kalach Pitchei Chokhmah 121:22