There were several interesting theories concerning the factors that determine the sex of the child. According to one, which owned Talmudic warrant, the sperm is male, the egg-cell female; whichever makes its entry second into the womb "subdues" the first and impresses its gender upon the offspring. Consequently the parent whose emission is delayed determines the child's sex. The same conclusion was also derived from a contrary premise, namely, that the will of the parent who first experiences an orgasm is paramount. This view, however, rather unreasonably insists that all men desire girl children, and all women, boys. Still a third opinion was based on a remarkable anatomical fable. Within the womb there are seven sacs, three at each side and one in the center. If the spermatozoa enter those at the right, the child will be a boy; the left sacs produce girls and the middle one, children who are sexless or hermaphroditic. Therefore, there mother can control the sex of her child by lying either on her right or left side. There were manifold infallible ways of discovering the sex of the child prior to birth. The male lies face-down in the womb, the female face-up (the corpse of a drowned man or woman floats in the same manner). At the instant when the child pushes its way into this world one can tell its sex by noting the direction in which its head is turned. But most of the prognostics did not necessitate waiting until they were no longer needed. The desired information could be obtained long before. Thus, if a pregnant woman drips some milk from her breast upon a board or rock, if it spatters in the child will be a boy; otherwise, a girl. Or, if the milk sinks in water, she will bear a girl, and if it floats, a boy. If her loins ache, she is carrying a boy, but if her belly pains, it is a girl. If she is quick about her housework and her spinning, she will have a son, while if she is sluggish and can barely get around, a daughter. The right-and-left leitmotif was also prominent. A right breast fuller than the left betokens a make heir; the same is indicated if, on rising from her seat, a woman leans on her right side; but if she feels the fetus knocking against her left side, it is a girl, and so on. These signs were evidently drawn from non-Jewish folklore, for the medieval literature abounds with parallels. It is noteworthy, though, that the Jewish sources retain these investigations and experiments to satisfy no mere curiosity, however justified the thirst for knowledge may be in this case, but rather to meet a pious need. They are meant for parents who reside a considerable distance from the nearest performer of circumcisions. Should they wait until the child is born to determine whether or not they require his services, it would be impossible to initiate their son into the covenant at that the prescribed time. Therefore science is pressed into the service of religion, and the summons can go out, if the prognostications so indicate, long before the boy has opened his eyes to the light of day. From: Joshua Trachtenberg, Jewish Magic and Superstition: A Study in Folk Religion. Copyright © 1939 Behrman's Jewish Book House, Inc. (published by Atheneum and reprinted by arrangement with the Jewish Publication Society of America), pp. 188-89.