If they performed the ḥalitza after three months, she does not need to wait three months and may marry immediately.

The Gemara infers from the latter clause of the baraita: It must be that the three months that are stated throughout the baraita are counted from the time of the husband’s death and not from the time of the ḥalitza of the yavam.

The Gemara asks: In what way is this case different from the case of a bill of divorce, where Rav said that the three months are counted from the time of the giving of the bill of divorce, and Shmuel said that the count is from the time of the writing of the bill. If a couple is secluded together after the bill of divorce is written, the bill of divorce is invalid. Therefore, there is no concern that they were secluded from that time. This is why Shmuel holds that the three months are counted from the writing. Rav apparently assumes that even so, the count always begins from the formal end of the marriage and not from the point from which there was no possibility of her becoming pregnant. Why, then, does the baraita not rule also in the case when a woman happens for levirate marriage, that the count should begin from the point of ḥalitza, since the marriage is only fully severed at that point?

Rava said: With regard to a yevama, all agree that the count begins from the time of her husband’s death. This can be derived through an a fortiori inference, as follows: If a prohibition that entails karet, i.e., the prohibition against engaging in relations with one’s brother’s wife in the event she is pregnant and not subject to levirate marriage, you have permitted after three months from the husband’s death, then in the case of a standard negative prohibition, such as the prohibition against engaging in relations with a woman within three months of the death of her previous husband, is it not all the more so clear that she should be permitted to remarry after three months from her husband’s death? Therefore, even Rav agrees that in this case, the count begins from the husband’s death.

§ The mishna states: And similarly, all other women may not be betrothed or marry until they have waited three months. The Gemara asks: Granted, a yevama has to wait, in accordance with the reason that we said, that if she is pregnant with viable offspring, consummating the levirate marriage would violate the prohibition against engaging in relations with one’s brother’s wife. But with regard to all other women, why shouldn’t they remarry immediately even if they are pregnant?

Rav Naḥman said that Shmuel said: It is due to the fact that the verse states with regard to Abraham: ''To be a God to you and your seed after you'' (Genesis 17:7), which indicates that the Divine Presence rests with someone only when his seed can be identified as being descended from him, i.e., there are no uncertainties with regard to their lineage. Therefore, to prevent any uncertainties concerning the lineage of her child, the woman must wait so that it will be possible to distinguish between the seed of the first husband and the seed of the second husband. After three months, if she has conceived from her previous husband, the pregnancy will already be noticeable.

Rava raised an objection from a baraita: Therefore, on account of the requirement to wait three months, a male convert and a female convert who were originally married to each other and converted need to wait three months before they may remarry following their conversion. Rava asks: Here, in this case, what reason is there to distinguish? Even if they do not wait and she is found to be pregnant, it is clear who the child’s parents are.

The Gemara explains: Here, too, there is a need to distinguish between seed that was sown in sanctity, i.e., a child conceived by a Jewish parents, and seed that was not sown in sanctity, i.e., a child conceived by gentile parents.

Rava stated a different reason for the need to wait: It is a rabbinic decree lest a child be born and be incorrectly identified as the son of his mother’s second husband when he is fact the son of her first husband. This could result in him marrying his paternal sister, unaware of the true relationship between them, or consummating a levirate marriage with the wife of his maternal brother under the misconception that his maternal brother was also his paternal brother. This would be prohibited because the prohibition to engage in relations with one’s brother’s wife is waived only in the case where there is a mitzva of levirate marriage, which applies only to paternal brothers.

Or in the event that his mother’s second husband died and he was assumed to be his only offspring, he would cause his mother to go out and be permitted to the general public because, under the misconception that he was the offspring of the deceased, he assumed that there was no mitzva of levirate marriage. Or, in the event that his maternal brother died childless and the brother’s widow became subject to levirate marriage, under the misconception that he was the paternal brother of the deceased he might perform ḥalitza and permit his supposed yevama to marry a man from the general public. To avoid these problems, the Sages decreed that a woman must wait before remarrying.

Rav Ḥananya raised an objection from a baraita: In all of those cases where the Sages prohibit a woman from marrying or consummating a levirate marriage, I identify that the prohibition is due to an ordinance instituted to prevent a violation of forbidden relations, and here, with regard to the prohibition against marrying within three months, it is due to an ordinance for the benefit of the offspring. Rav Ḥananya explains the challenge: And if it is so that Rava’s understanding of the prohibition against marrying within three months is correct, then all of the cases of forbidden marriages are due to an ordinance to prevent violation of forbidden relations. However, the baraita indicates otherwise.

The Gemara defends Rava’s opinion and explains that the baraita can be interpreted in a way that is consistent with his understanding: When the baraita says that this prohibition is due to an ordinance for the benefit of the offspring, it means that due to the prohibition the offspring will not encounter a prohibition of forbidden relations.

§ The Gemara analyzes the prohibition against marrying before three months have passed: Granted, she should not wait for only two months and then marry, as this is still a case that could give rise to an uncertainty whether the child born to her seven months after remarrying is nine months old, i.e., counting from conception, and it is the offspring of the first husband, or whether the child is only seven months old and is the offspring of the latter husband.

However, let her wait only one month and then marry, and then, since it is presumed that a baby born during its eighth month since conception is not viable but a baby born during its seventh or nine month is viable, if after seven months since remarrying she gives birth, then the child is clearly seven months old and is the offspring of the latter husband, and if after eight months since remarrying she gives birth, then this child is clearly nine months old and is the offspring of the first husband. Why, then, is there a need to wait three months?

The Gemara explains: Even if she gave birth after eight months since remarrying one could say that the child is the offspring of the latter husband, as perhaps she waited one month after remarrying and conceived only then. As such, the baby would be only seven months old, and that would explain its viability.

The Gemara asks further: But let her wait for two and a half months and then marry, as, if after seven months since remarrying she gives birth, then this child is clearly seven months old and is the offspring of the latter husband. And if after six and a half months since remarrying she gives birth, then this child is clearly nine months old and is the offspring of the first husband, because if one would suggest it is the offspring of the latter husband, in that case it would be six and a half months old, at which age it cannot survive.

The Gemara objects: Even if after six and a half months since remarrying she gave birth, one could say that the child is the offspring of the latter husband, as Mar Zutra said: Even according to the one who says that a woman who gives birth after nine months does not give birth after an incomplete number of months, i.e., she carries for a full nine months, nevertheless, a woman who gives birth after seven months can give birth after an incomplete number of months, and therefore it is possible that the baby was actually born after six and a half months.

This fact is derived from the verse concerning the birth of Samuel the prophet, as it is stated: ''And it came to pass, when the seasons of the days had come, that Hannah conceived, and bore a son'' (I Samuel 1:20). How much time is indicated by the phrase ''the seasons of the days''? The minimal sense of the word ''seasons'' is two, and since each season of the year is three months, that indicates six months. The minimal sense of the word ''days'' is two. Accordingly, one may conclude that Samuel the prophet was born after six months and two days.

The Gemara suggests further: But let her wait any minimal amount of time, less than a month, and then marry, and then when three months after the end of her first marriage are complete, examine her body to see if she is noticeably pregnant. If she is, then perforce the baby is the offspring of her previous husband because a pregnancy is not noticeable until three months.

Rav Safra said: This solution is not possible because one does not examine the bodies of married women so as not to shame them before their husbands. The Gemara suggests: But let her be examined through the way she walks, since after three months a pregnant woman walks differently than a woman who is not pregnant.

Rami bar Ḥama said: A woman who conceived from her previous husband would mask herself by purposefully walking in a manner in which her pregnancy will not be discerned, so that her child will be identified as the son of her new husband in order that her child will ultimately inherit her new husband’s property. Therefore, it is impossible to rely upon a test of this kind. In summary, the Gemara has demonstrated that it would be ineffective to wait any less than three months.

§ The Gemara asks: In cases where we are convinced that she is pregnant, let her marry immediately, as the reason to wait three months does not apply. Why, then, is it taught in a baraita: A man may not marry a woman who is pregnant with the child of another man, nor a woman who is nursing the child of another man; and if he transgressed and married her, he is penalized for violating the prohibition, and he must divorce her and may never take her back?

The Gemara explains: This prohibition is a rabbinic decree lest she become pregnant a second time and her original fetus will be deformed into the shape of a sandal fish. The Gemara asks: If so, even if his wife is pregnant with his own child, the same concern applies.

The Gemara responds: She is permitted to engage in relations, both if one holds in accordance with the one who said that a young girl, for whom it is dangerous to become pregnant, is permitted to engage in relations using a contraceptive resorbent placed at the entrance to her womb, then also a woman pregnant with her husband’s child may engage in relations using a resorbent, and similarly if one holds in accordance with the one who said a young girl is permitted to engage in relations in her usual manner and Heaven will have mercy upon her and prevent any mishap, then in this case as well a pregnant woman should continue to engage in relations and Heaven will have mercy upon her.

The Gemara objects: But here, too, in the case of a woman who is pregnant with the child of another man, these solutions could be employed: Both if one holds in accordance with the one who says that a young girl may engage in relations using a resorbent, in this case as well she may do so using a resorbent, and similarly if one holds in accordance with the one who says that Heaven will have mercy upon her, in this case as well Heaven will have mercy upon her.

The Gemara suggests a different reason for the prohibition against marrying a woman who is pregnant with the child of another man: Rather, it is due to the damage that could be caused to the fetus by the pressure applied to it at the time of intercourse. The Gemara asks: If so, even if his wife his pregnant with his own child, the same concern applies. The Gemara explains: When it is his own child, he has mercy upon it and tries not to apply too much pressure. The Gemara asks: But here, too, when it is the child of another man, he will have mercy upon it, as certainly one is careful not to cause harm to any human life and will be careful not to press down too hard.

The Gemara suggests a different reason: Rather, the reason for the prohibition is that a typical pregnant woman is poised to nurse her child once it is born;