How's this for timing:
If Christ's birthday is around the 25th of December (obviously, the Jewish calendar is different, but this date on our Julian calendar is pretty close to their date), then his conception was around the time of Passover in late March or early April.
Coincidence? I think not...
I can't take credit for this scholarly thought...I read it in my "Jesus the One and Only" study guide (a Beth Moore study).