Du'a for children and pregnancy

رَبِّ إِنِّي لِمَآ أَنزَلۡتَ إِلَيَّ مِنۡ خَيۡرࣲ فَقِيرࣱ‏

Rabbi innee limaa anzalta ilayya min khayrin faqeer

My Lord! I am needy of whatever good Thou sendest down for me

Qur'an 28:24 (Al-Qasas)