Answer
(Fatwa: 1705/1343/B=1431)
Recite the following dua extensively:
رَبِّ لَا تَذَرْنِي فَرْداً وَأَنتَ خَيْرُ الْوَارِثِينَ [الأنبياء : 89]
Also the following practice is very much tested:
Take two eggs daily in the morning and boil them and peel them and write the following ayah on one egg which the husband would eat: وَالسَّمَاء بَنَيْنَاهَا بِأَيْدٍ وَإِنَّا لَمُوسِعُونَ [الذاريات : 47]
On the other egg write the following ayah which the wife would eat: وَالْأَرْضَ فَرَشْنَاهَا فَنِعْمَ الْمَاهِدُونَ [الذاريات : 48]
This should be done for forty days without any gap, and during this period they should have intercourse as well.
Allah (Subhana Wa Ta’ala) knows Best
Darul Ifta,
Darul Uloom Deoband