There has been quite a lot of discussion on this already in the Feminism section... those of us who have been through IVF seem noticeably less bothered than those who haven't.
Dh had to provide one sample before we started treatment. All others had to provided in very narrow timescales. We had 9 failed rounds of IUI and one successful IVF. In this, I tested to see when ovulation took place. I then phoned the clinic at the next available opportunity, they gave me an appointment to come in, DH had to be there an hour earlier to provide a sample. We had about 2 hours notice each time.
We were both working full time and going to a good NHS and private clinic in central london. It would not have been possible to produce the sample at home. Few/no employers would be happy with a sperm sample in the fridge, and wanking into a small vial at work would have been much worse. Also a sackable offence to have pornography in the office.
I couldn't have helped - i had to work and mentally prepare myself for undergoing a moderately uncomfortable procedure followed by massive emotional swings over the next two weeks let alone avoiding contamination or being in recovery following egg collection. If DH had not been able to produce a sample so the miserable treatment and hardcore drugs were for nothing, it might well have meant the end of our marriage.
So long as the porn is at the 'reader's wives' end of the scale rather than double anal, I really don't have a problem with it in this instance. If men don't need it, fine, they don't have to use it. If they do, it is probably better all round that it is either provided or they are told to bring their own and take it away again with a list of very local newsagents and a recycling bin provided.