In verse 67 of Surah Al-Mu’min, Allah Almighty says about the phases of life:

It is He Who has created you from dust then from a sperm-drop, then from a leech-like clot; then does he get you out as a child: then lets you reach your age of full strength; then lets you become old,- though of you there are some who die before;- and lets you reach a term appointed; in order that ye may learn wisdom.

Al-Mu’min – The Believer – 40:67 (Sura: 40, Verse: 67)