Hippolytus

“ For from [5] (the moment) of birth [6] the ascension of the zodiacal sign rising in the heaven should be closely watched, [7] since the Chaldeans, determining (from this) the horoscope, frame the configuration of the stars in accordance with the ascension (of the sign) ; and they term this—disposition, in accordance with which they devise their predictions. But neither is it possible to take the birth of persons, falling under consideration, as I shall explain, nor is the horoscope infallible, nor is the rising zodiacal sign apprehended with accuracy. ”

“ And this is not strange, since also women, when themselves compared with themselves, at times are observed having a strong disposition towards conception, but at times with no such tendency. And when this is so, it is impossible to say with accuracy when the deposited seed coalesces, in order that from this time the Chaldeans may fix the horoscope of the birth. ”

“ And, moreover, as women [14] differ from one another in the other parts of the body, both as regards energy and in other respects, so also (it is reasonable to suppose that they differ from one another) in respect of energy of womb, some conceiving quicker, and others slower. ”