A tumtum’s condition may be the result of an intrinsic genetic defect, in which case, the condition will not change. Under certain circumstances, the physical covering that hid the sexual organ may be removed (in the language of the Gemara it is nikra, or “torn” off) and the individual can be identified as male or female. Nevertheless, the likelihood that a man whose testicles have developed within his body will be able to have children is slim at best. This is certainly the case in someone who was truly a tumtum, that is to say, that their sexual organs did not develop because of a low level of hormones. In such a case, even if the person’s physical situation improves, he will not be able to father children.
ל׳ בכסלו ה׳תשע״ב (December 26, 2011)
While discussing the implications of finding that a firstborn animal is a tumtum or an androgynous (see the discussion on yesterday’s daf, or page), the Gemara brings support from the way these conditions are viewed by Jewish law in the context of marriage and divorce. For example, a baraita teaches that if a tumtum – who does not appear to have any external sexual organs that would identify it as either male or female – were to betroth a woman, his betrothal is valid, i.e. he must give her a divorce, since the tumtum might be male and a full marriage took place. If the tumtum was betrothed by a man, the betrothal is valid, and the man would be forbidden to marry any of the tumtum’s relatives, since the tumtummight be female, and a full marriage took place.
The Gemara also brings baraitot that consider the possibility that a tumtum’s gender may be determined, and that in such a case it is likely that the tumtum will be found to be a saris, that is, a eunuch who cannot reproduce.