What is the ruling on selling birth control pills?

It is permissible to sell birth control pills unless their medical harm is proven. It is not permissible to sell them to one who is known to use them in a haram (forbidden) way, such as a woman who uses them without her husband's knowledge, or one who has no valid excuse for preventing pregnancy. And if it is highly probable that the buyer will use them in a haram way, then it is not permissible to sell them to him.