You automatically lose the debate by invoking Hitler. As if you can draw some perverted moral equivalency between Hitler and IVF.
You sound just like the "if God had wanted us to fly he'd have given us wings" crowd.
The difference between the factions here is that some of us believe God loves us unconditionaly and some of us are afraid of God.
I believe the former is true and I also believe the greatest Mortal sin is to interpret the bible to suit ones ends.
I made an analogy, I did not invoke Hitler. You can't self define the greatest sin, friend, that makes you god. You are interpreting the bible, not I. I am accepting what God has ordained by His Church which speaks infallibly on such issues. You are fallible and very wrong in this case. God does love us unconditionally. That does not mean we are to presume upon His mercy. One can't commit grave sin after grave sin and call it not a sin. That is presumption. We all can be blinded to the truth if we immerse ourselves in grave sin.