"Contraceptives were discriminated from abortifacients in theory. In practice it was difficult to distinguish between abortive and contraceptive effects of some potions, and according to the most authoritative writer, Soranos, this difficulty attended every potion he would recommend. Use off the sterile period, precoital pessaries, postcoital exercise, and gum for the male genitals were all intended to work only contraceptively. All of the latter methods, however, did involve an attack on the sperm; even the sterile period was supposed to be sterile because the menstrual flow would affect the seed. It is also germane to the Christian judgment that almost all the methods used were intended to achieve only temporary sterility. Only a few potions were apparently intended to sterilize permanently. The other potions and all the other means proposed were ways by which pregnancy might be postponed or a given time."