<b>And God remembered Rachel (Gen. 30:22).</b> May our master teach us whether a man may recite the prayer “May it be Your will that my wife give birth to a son” if she is already pregnant. Our masters teach us: The man who prays “May it be Your will that my wife give birth to a son” when she has already conceived is uttering a vain prayer (and is taking the Lord’s name in vain).
R. Huna, however, maintained in the name of R. Yosé: Though we have been taught that the husband of a pregnant woman who prays “May it be Thy will that my wife bear a son” is uttering a vain prayer, this is not so. In fact, he may pray for the birth of a son even as she commences labor, for it is not difficult for the Holy One, blessed be He, to convert females into males and males into females. He quoted a verse from Jeremiah to support this statement: <i>Then I went down to the potter’s house, and behold, he was at his work on the wheels. And whensoever the vessel he made of the clay was marred in the hand of the potter, he made it again another vessel, as it seemed good to the potter to make it</i> (Jer. 18:3–4). And did not the Holy One, blessed be He, say to Jeremiah: <i>O house of Israel, cannot I do with you as this potter?</i> (ibid., v. 6).
You find that this happened to Leah. After she had given birth to six sons, she foresaw in a dream that Jacob would ultimately have twelve sons. Since she had already given birth to six sons, and was pregnant with her seventh child, and the two handmaidens had each borne two sons, making ten sons in all, Leah arose and pleaded with the Holy One, saying: Master of the Universe, twelve tribes are to descend from Jacob, and since I have already given birth to six sons, and am pregnant with a seventh child, and each of the handmaidens has born two sons, which accounts for ten sons, if the child within me is a male, my sister will not bear even as many sons as the handmaidens. The Holy One, blessed be He, hearkened to her prayer and converted the fetus in her womb into a female, as it is said: <i>And afterwards she bore a daughter and called her Dinah</i> (Gen. 30:21). The masculine form of <i>afterwards</i> is written in this verse, and not the feminine form (thus signifying that the fetus was originally that of a male child).
Why did Leah call her Dinah? Because the righteous Leah had pleaded for justice (<i>din</i>) before the Holy One, blessed be He. The Holy One, blessed be He, said to her: You are merciful, and so I shall be merciful to her. Forthwith, <i>And God remembered Rachel</i>.