What are monthly profections?

Monthly profections come from Vettius Valens' Anthologies, written in the second century CE. The technique works by advancing the Ascendant one sign per month within the annual profection year. Month 1 starts from the same sign as the annual profection; each subsequent month moves one sign forward. The ruler of each monthly sign becomes the Lord of the Month for that period.

Month 1 always produces a double activation: the Lord of the Year and the Lord of the Month are the same planet. Planets that rule two signs (Mars rules Aries and Scorpio; Saturn rules Capricorn and Aquarius; Mercury rules Gemini and Virgo; Jupiter rules Sagittarius and Pisces; Venus rules Taurus and Libra) will produce a second month where Lord of Year and Lord of Month coincide. Natal planets falling in the monthly sign are also activated as secondary significators for that period.