Srimad Bhagavatam Canto 04, Chapter 22, Text 53

SB 4.22.53

evam adhyatma-yogena
karmany anusamacaran
putran utpadayam asa
pañcarcisy atma-sammatan
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Being situated in the liberated position of devotional service, Prthu Maharaja not only performed all fruitive activities but also begot five sons by his wife, Arci. Indeed, all his sons were begotten according to his own desire.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
As a householder, Prthu Maharaja had five sons by his wife, Arci, and all these sons were begotten as he desired them. They were not born whimsically or by accident. How one can beget children according to one’s own desire is practically unknown in the present age, Kali-yuga. In this regard the secret of success depends on the parents’ acceptance of the various purificatory methods known as samskaras. The first samskara, the garbhadhana-samskara, or child-begetting samskara, is compulsory, especially for the higher castes, the brahmanas and the ksatriyas. As stated in Bhagavad-gita, sex life which is not against religious principles is Krsna Himself, and according to religious principles, when one wants to beget a child he must perform the garbhadhana-samskara before having sex. The mental state of the father and mother before sex will certainly affect the mentality of the child to be begotten. A child who is begotten out of lust may not turn out as the parents desire. As stated in the sastras, yatha yonir yatha bijam. Yatha yonih indicates the mother, and yatha bijam indicates the father. If the mental state of the parents is prepared before they have sex, the child which they will beget will certainly reflect their mental condition. It is therefore understood by the words atma-sammatan that both Prthu Maharaja and Arci underwent the garbhadhana purificatory process before begetting children, and thus they begot all their sons according to their desires and purified mental states. Prthu Maharaja did not beget his children out of lust, nor was he attracted to his wife for sense gratificatory purposes. He begot the children as a grhastha for the future administration of his government all over the world.
Srimad Bhagavatam Canto 04, Chapter 22, Text 52
Srimad Bhagavatam Canto 04, Chapter 22, Text 54