What is the ruling of Islamic law regarding a father forcing his married daughter to abort her fetus—which would have exceeded 40 days of gestation—in exchange for him covering her study expenses, and threatening to disown her and be displeased with her if she refuses?

Indeed, having offspring is one of the greatest objectives of marriage. The condition imposed by the wife's guardian on the husband, that his wife should not conceive without a legitimate Shar'i excuse, is a void condition and does not necessitate fulfillment. It is not permissible to abort a fetus after forty days unless there is a very strong legitimate Shar'i justification, such as a danger to the mother's life. The husband must fulfill his duty towards his wife and bear her expenses. There is no obedience to a creature in disobedience to the Creator, and obedience to Allah takes precedence over obedience to a parent regarding abortion.