Valmiki Ramayana Ayodhya Kanda Sarga 74 Shloka 4
Original Shlokaभ्रूणहत्यामसि प्राप्ता कुलस्यास्य विनाशनात्। कैकेयि नरकं गच्छ मा च भर्तु स्सलोकताम्।।2.74.4।।
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अस्य कुलस्य of this race, विनाशनात् by destruction, भ्रूणहत्याम् the sin of killing an unborn, प्राप्ता असि you have earned, कैकेयि Kaikeyi, नरकम् to hell, गच्छ go, भर्तुः to husband, सलोकताम् similar world, मा च not attain.
O Kaikeyi by destroying this race you have earned the demerit of killing an embryo and shall enter hell. You shall never attain the same state of living, in the afterworld of your husband.