The basic principle in Islamic law is the prohibition of harm, as he (peace be upon him) said: “do no cause harm and do not retaliate harm.”
If a woman consults a trustworthy Muslim doctor, and he permitted her to use medications that delays the onset of menstruation until she performs all the rites of Hajj without any harm to be caused either in terms of hormonal disturbances or the ill effects that follow, then she can go ahead to use the medicine, and the Hajj is correct by Allah’s will.