@CBC is making a great point.
@ilherman, where's the Rav Moshe? And are you sure he's addressing issue A? It really wouldn't make any sense.
What is the great point? No one is talking here about point B which is avoided even as per you by taking pills.
And you say that it wouldnt make sense what R Moshe said. How many times have you finished Daled Chelkie Shulchan Aruch?
I will explain the simple answer. There is a Mitzvah, so you're gonna say that whoever is pregnant is currently being Oiver on that Mitzvah? And whoever can't have kids is Oiver on that Mitzvah. If you can not produce kids now for whatever reason then you are not oiver. Now lets say if someone is pushing off the Mikvah with two days so his wife can't get pregnant that is as per some called Oiver on the Mitzvah. Taking pills makes you like someone who can't have kinds. Now of course Hashkafah wise there is a huge difference between someone who can not have kids and someone who takes pills. But Mesh wants to know why mix Halachah and Hashkafah. I will look for the Igrus Moshe tomorrow. And please don't reply by what your Das Bal Habayis says. If you have a Halachdig argument you're more than welcome.