Is it permissible to supplicate and implore Allah for sustenance with another child after a hysterectomy, even though doctors have confirmed the impossibility of pregnancy, given that there are cases of ectopic pregnancies that develop outside the womb?

It is advisable to be content with Allah's decree, for whatever Allah decrees for a believer is good for him. It is obligatory to show patience and seek reward for whatever befalls one. As for supplicating for pregnancy when it is usually impossible, this is considered an تجاوز (transgression) in supplication. The reference for knowing what is impossible or permissible in this regard is the specialists.