Few of my readers have requested mantras which may help them to concieve/get pregnant. A good friend of mine had given me a book titled "Vishnusahasranama vishistha stotragalu" written by vidya vachaspati Sri Aralumallige Parthasarathi. Read more about Dr.Parthasarathy on Wikipedia. This book has mantras which addresses specific problems. Belief is everything! If you believe and trust Vishnu Sahasranama do chant this.
Buy a copy of this book if possible.
Source : ವಿಷ್ಣು ಸಹಸ್ರನಾಮ ವಿಶಿಷ್ಟ ಸ್ತೋತ್ರಗಳು
Vishnusahasranama vishistha stotragalu
Author : Dr. Aralumallige Parthasarathy
"Shubhango Lokasarangaha
sutantustantuvardhanaha
Indrakarmaa mahakarmaa
krutakarmaa krutagamaha"
The book also reccommends to chant vishnusahasranama everyday for good results. May god bless you all.