When I did the teaching on this, I think I got one part wrong, and I've corrected it on the article.
Defraud ye not one the other, except it be with consent for a time, that ye may give yourselves to fasting and prayer; and come together again, that Satan tempt you not for your incontinency.
-1Co 7:5
I had previously taught that all sexual intercourse between a husband and wife should cease during fasting. However, it should cease only IF both parties agree. This is to say that there is no sexual activity WITH CONSENT, which is mutual agreement. If one or both spouses enter into temptation, then sexual intercourse would be allowed, even during times of fasting because it is best to not sin, but if possible, it is better not to do so, that either one or both spouses may cleanse the flesh completely during the fast.
I'm sorry that I taught that on the audio teaching; I can't go back and change it now.