pravrtto varito garbham
saptva viryam upasrjat
antah-vatnyam—pregnant; bhratr-patnyam—with the brotherís wife; maithunaya—desiring sexual enjoyment; brhaspatih—the demigod named Brhaspati; pravrttah—so inclined; varitah—when forbidden to do so; garbham—the son within the abdomen; saptva—by cursing; viryam—semen; upasrjat—discharged.
When the demigod named Brhaspati was attracted by his brotherís wife, Mamata, who at that time was pregnant, he desired to have sexual relations with her. The son within her womb forbid this, but Brhaspati cursed him and forcibly discharged semen into the womb of Mamata.
The sex impulse is so strong in this material world that even Brhaspati, who is supposed to be the priest of the demigods and a very learned scholar, wanted to have a sexual relationship with his brotherís pregnant wife. This can happen even in the society of the higher demigods, so what to speak of human society? The sex impulse is so strong that it can agitate even a learned personality like Brhaspati.
Link to this page: https://prabhupadabooks.com/sb/9/20/36