Brihat Parashara Hora Shastra
षष्ठाष्टमव्ययस्थो वा नीचो वा शत्रुराशिगः । सुतेशश्च सुते तस्य कष्टाद् पुत्रं विनिर्दिशेत् ॥ ८॥
If Putr‟s Lord is in Ari, Randhr, or Vyaya Bhava, or be in an inimical Rāśi, or be in fall, or in Putr itself, the native will beget issues with difficulty.
english translation
SaSThASTamavyayastho vA nIco vA zatrurAzigaH । sutezazca sute tasya kaSTAd putraM vinirdizet ॥ 8॥
hk transliteration by Sanscript