Yes and no; normally no.
Once you ovulate, the egg can only be fertilised for about 24 hours (some say up to 48 hours). So if you have a 28 day cycle and ovulate in the middle, ie day 14, by the time AF is due at day 28 your egg definitely is not viable anymore. However, if you are not sure that you ovulated, it is possible to get pregnant shortly before you think your next AF is due, when you in fact are having an especially long cycle.