"And the woman conceived and bore a son" (Exodus 2:2). But was she not already pregnant for three months? Rather, Scripture likens her giving birth to her conceiving: just as her conceiving was without pain, so too her giving birth was without pain. From here we learn concerning the righteous women that they were not included in the decree of Eve. "And she saw him, that he was good" (Exodus 2:2): Toviah was his name. Another interpretation: he was fit for prophecy. Another interpretation: he was born already circumcised. Another interpretation: at the hour when Moses was born, the house was filled with light, and therefore it says "that he was good"; it is written here "that he was good," and it is written there "And God saw the light, that it was good" (Genesis 1:4). "And she hid him three months" (Exodus 2:2): for the Egyptians counted only from the hour that he had taken her back, but she had been pregnant three months beforehand.
Moses Born Painlessly and Filling the House with Light
Midrash Aggadah, Exodus 2:2
ותהר האשה ותלד בן. והלא מעוברת היתה כבר משלשה חדשים, אלא מקיש לידתה להורתה, מה הורתה שלא בצער, אף לידתה שלא בצער, מכאן לנשים הצדקניות שלא היו בפתקה של חוה: ותרא אותו כי טוב הוא. טוביה שמו: ד"א טוב לנביאות: ד"א שנולד מהול: ד"א בשעה שנולד משה נתמלא הבית אורה, ולכך אמר כי טוב, כתיב הכא כי טוב הוא, וכתיב התם וירא אלהים את האור כי טוב (בראשית א' ד'): ותצפנהו שלשה ירחים. שלא היו מונים המצרים אלא משעה שהחזירה, והיא היתה מעוברת מקודם שלשה ירחים: