We're not just sex organs. God did give us brains and we have our free will.
That's right. We are distinctive as male and female in a wide variety of ways which are relevant to many aspects of life.
God did give us brains and we have our free will.
We can use our brains to discern that our created nature includes the fact that, by design, the "cause" of sexual intercourse produces the "effect" of new human beings. We can use our free will to reject that truth and engage in the "cause" behavior while acting to prevent the "effect."
In a similar way, we can engage in the "cause" behavior of eating, while rejecting the "effect" of nutrition, by vomiting the food. This is simple scientific observation, and even the ancient Greeks and Romans understood it. They also understood that a society collapses when enough people live "in the moment" of sexual pleasure while denying the future.
This is where contraception differs from ethical healthcare. The purpose of ethical healthcare is to restore health: "duh", you're thinking, but let me specify: to cure disease, to heal injury, to repair a defect or deformity, to strengthen weak or failing organs and systems, with a view to bring the body back towards full functionality.
That's what justifies drugs, devices, and surgery: the real definition of medicine as the "healing arts."
The purpose of contraception is obviously to temporarily or permanently destroy function. It is just as immoral as a non-medically-indicated removal or an eye or a nose, a castration, amputation, or female genital mutilation.
It shows a seriously perverse rejection of the human personal design --- it's "anti-humanistic" --- and, if you believe in God, also anti-divine.