Is it permissible to pray for a male child for a pregnant woman in her fourth month?

It is permissible for a Muslim to ask Allah for whatever they desire of the good in this world and the Hereafter. There is no impediment to asking Him, the Almighty, to bless you with a male child, based on the generality of the Prophet's (peace be upon him) saying: "Let each of you ask his Lord for all his needs, even for the shoelace of his sandal." Narrated by Abu Ya'la. However, if you know through a medical examination that it is a female, then it is not permissible to supplicate for a male child at that point, as that would be an transgression in supplication.