Is it permissible to determine the sex of the fetus by advising specific days for intercourse to conceive a boy or a girl, while believing that Allah is the ultimate Disposer of all affairs?

There is no objection to choosing the sex of the fetus by trying to have intercourse at specific times, as the Islamic Fiqh Academy has issued a resolution to that effect, with the caveat that doctors have stated that there is no confirmed effectiveness for this method.