(This may not be at a specific time...
(This may not be at a specific time; rather it may be parallel to that of physical growth.) On the subject of the creation of the foetus, it is narrated from the Prophet (S): “The seed in the womb of the mother (takes) 40 days to become a clot, then after 40 days it becomes a lump of flesh (foetus); when the child is 4 months old, by the command of Allāh (SwT), 2 Angels give the foetus a spirit (rūĥ) and specify the sustenance (Rizq), period of living, deeds (A°māl), prosperity and adversity of the child.”[^1] It is perhaps for this reason that it has been suggested that especially after the 40th day of intercourse, one should be extra careful when preparing food.
The food must be ritually clean and ĥalāl as this will have an impact on the child.[^2] Imām as-Ŝādiq (as) also described the process of creation as follows: “After the completion of the materials of the body, Allāh (SwT) sends two Angels who have the duty of the creation of the child, and by the permission of Allāh (SwT), they create the ears and eyes and all the inner and outer organs (limbs) of the body.”[^3] In Imām Husain’s (as) Du°a of °Arafāt, he refers to the process of creation and attempts to count the blessings bestowed by Allāh (SwT) in the following manner: “You originated me by Your blessing before I was a thing remembered.
You created me from dust, then gave me a place in the loins (of my fathers), secure from the uncertainty of Fate and the vagaries of the ages and the years. I remained a traveller from loin to womb in a time immemorial of past days and bygone centuries. In Your tenderness, bounty and goodness toward me You did not send me out into the empire of the leaders of disbelief, those who broke Your covenant and cried lies to Your messengers.
Rather, You sent me out to that guidance which had been foreordained for me, the way which You made easy for me and in which You Nurtured me. And before that You wert kind to me through Your gracious fashioning and abundant blessings. You originated my creation from a sperm-drop spilled and madest me to dwell in a threefold gloom among flesh, blood and skin. You gave me not to witness my creation, nor didst You entrust me with anything of my own affair.
Then You sent me out into the world for the guidance that had been foredained for me, complete and unimpaired.” ^4 Imām Zain al-°Abidīn (as) in his Du°ā after Ŝalāt al-Lail in Saĥīfah Sajjādiya also mentions this amazing period of the foetus and of breastfeeding.