Answered by Sayyidi Habib Umar bin Hafiz (may Allah protect him and benefit us by him)
What can someone who has not been able to conceive recite?
Our Shaykh, Habib `Attas al-Habashi, used to recommend reciting Surat al-Fatihah 41 times between the Sunnah and Fard of Fajr with the intention of being blessed with a child.
Also recite the following verses 100 times a day or more or less:
رَبِّ هَبْ لِي مِن لَّدُنْكَ ذُرِّيَّةً طَيِّبَةً إِنَّكَ سَمِيعُ الدُّعَاء
Rabbi hab li milladunka dhurriyyatan tayyibatan innaka sami`u-du`a’
“O my Lord! Grant me from You pure descendants, for You hear all prayers!” (Al `Imran, 3:38)
رَبِّ لا تَذَرْني فَرْداً و أَنْتَ خَيْرُ الوارِثينَ
Rabbi la tadharni fardan wa anta khayrul-warithin
“O my Lord! Leave me not without offspring, and You are the best of inheritors.” (Al-Anbiya’, 21:89)
رَبَّنَا هَبْ لَنَا مِنْ أَزْوَاجِنَا وَذُرِّيَّاتِنَا قُرَّةَ أَعْيُنٍ وَاجْعَلْنَا لِلْمُتَّقِينَ إِمَامًا
Rabbana hab lana min azwajina wa dhurriyyatina qurrata `ayun wa’ja’lna lilmuttaqina imama
“Our Lord! Grant unto us wives and offspring who will be the comfort of our eyes, and give us (the grace) to lead the righteous.” (Al-Furqan, 25:74)