Horoscopes Become Self-Fulfilling Prophecies

I learned today that Horoscopes become self-fulfilling prophecies… If Believed!

Astrology is based on the premise that our Destinies are fixed at the moment of our birth as a result of the position of the Stars and Planets.

This doesn’t make sense, because what is so significant about the day we come out of the womb??? If Astrology is based on fact, than shouldn’t it be measured at the moment of our conception???