No, I don’t think we do. The fact is, pregnancy itself has a significant rate of producing children with birth defects. My first born was born with several birth defects. I would love for you to come through my computer screen and tell me to my face that she shouldn’t have been born! Because we don’t know what caused her birth defects, there was considered to be a slightly elevated risk of subsequent children having birth defects, but we still had more children, who did not have birth defects. Even if I had known we had a real increased risk of birth defects, we would have still had more children. Birth defects are only one tiny drop in the comprehensive ocean of lousy things that can happen to people. They are not a fate worse than death or a fate worse than non-existence. So, no. We are under no moral obligation to do everything within our power to make certain that children with birth defects don’t exist. If I was temporarily on a class X medication, I would probably abstain to avoid pregnancy at that time. Otherwise, I would use NFP, as I usually do when I am not trying to be pregnant. If a time came that we wanted to be pregnant again, I would discontinue the medication first, if possible.