בְּטֶ֥רֶם תָּחִ֖יל יָלָ֑דָה בְּטֶ֨רֶם יָב֥וֹא חֵ֛בֶל לָ֖הּ וְהִמְלִ֥יטָה זָכָֽר׃
她還未感到劇痛，就生產了；陣痛還沒有臨到她，就生下一個男孩。
Rashi
When she has not yet travailed When Zion has not yet travailed with birth pangs, she has borne her children; that is to say that her children will gather into her midst, which was desolate and bereft of them, and it is as though she bore them now without birth pangs, for all the nations will bring them into her midst.
Ibn Ezra
תחיל She travailed. Comp. חיל trembling (Ps. 45:7). Before she travailed she brought forth. This is a figurative expression, indicating, that the Israelites will return to Zion, without any difficulty, like a woman, that bears children without troubles.
Rashi
she has been delivered of a male child Heb. וְהִמְלִיטָה. Any emerging of an embedded thing is called הַמְלָטָה. And הַמְלָטָה is esmoucer, or eschamocier in O.F., to allow to escape.