7. [One who says:] “I am a nazir when a son will be [born] to me,” and a son was born to him —- he is a nazir. [If] a daughter, or one of unknown gender, or an androgyne was born to him —- he is not a nazir. If he said: “When I shall see that there will be [born] to me a child” —- even [if there] is born to him a daughter, or one of unknown gender, or an androgyne —- he is a nazir.

[If] his wife lost the baby, he is not a nazir. R’ Shimon says: He should say: “If it was [a] viable [child], I am a nazir by [previous] obligation, but if not, I am a nazir voluntarily.” [If] she again gave birth, he is a nazir. R’ Shimon says: He should say: “If the first was viable, the first [nezirus] was obligatory, and this one is voluntary; but if not, the first [nezirus] was voluntary, and this one is obligatory.”