וַתַּ֣הַר עוֹד֮ וַתֵּ֣לֶד בֵּן֒ וַתֹּ֗אמֶר עַתָּ֤ה הַפַּ֙עַם֙ יִלָּוֶ֤ה אִישִׁי֙ אֵלַ֔י כִּֽי־יָלַ֥דְתִּי ל֖וֹ שְׁלֹשָׁ֣ה בָנִ֑ים עַל־כֵּ֥ן קָרָֽא־שְׁמ֖וֹ לֵוִֽי׃
Y concibió otra vez, y parió un hijo, y dijo: Ahora esta vez se unirá mi marido conmigo, porque le he parido tres hijos: por tanto, llamó su nombre Leví.
Rashi on Genesis
הפעם ילוה אישי THIS TIME WILL MY HUSBAND BECOME ATTACHED TO ME — Because the Matriarchs were prophetesses and knew that twelve tribes would issue from Jacob and that he would have four wives, she said, “From now he will have no fault to find with me, for I have assumed my full share in giving him children” (Midrash Tanchuma, Vayetzei 9).
Rashbam on Genesis
על כן קרא שמו לוי, one may assume that it was Yaakov who gave the boy this name. (compare Kimchi)
Sforno on Genesis
הפעם ילוה, I have by now acquired a tendency, a justified presumption, חזקה, of producing numerous children. Our sages in Yevamot 64 consider an occurrence thrice repeated as establishing such a presumption.