King Indra said: In the womb of this woman, the wife of the demon Hiranyakasipu, is the seed of that great demon. Therefore, let her remain in our custody until her child is delivered, and then we shall release her

Expressions researched:
"King Indra said: In the womb of this woman, the wife of the demon Hiranyakasipu, is the seed of that great demon. Therefore, let her remain in our custody until her child is delivered, and then we shall release her"

Srimad-Bhagavatam

SB Canto 7

King Indra said: In the womb of this woman, the wife of the demon Hiranyakasipu, is the seed of that great demon. Therefore, let her remain in our custody until her child is delivered, and then we shall release her.

SB 7.7.9, Translation and Purport

King Indra said: In the womb of this woman, the wife of the demon Hiranyakasipu, is the seed of that great demon. Therefore, let her remain in our custody until her child is delivered, and then we shall release her.

Indra, the King of heaven, decided to arrest Prahlāda Mahārāja's mother because he thought that another demon, another Hiraṇyakaśipu, was within her womb. The best course, he thought, was to kill the child when the child was born, and then the woman could be released.