If she's housed with a cock, then it's safe to assume that at least most of her eggs are fertile. Don't let that put you off eating them though, as anyone who's actually eaten fertile eggs can tell you that there is absolutely no difference in the taste. We had a rooster for all of 6 months. We did not notice any difference at all in the taste or texture of the eggs once we introduced him to our hens that were already laying, nor did we notice any difference after we had to get rid of him. Some of the hens were not fans of the rooster and never did let him mount them apparently. When we decided to incubate some of the eggs there were some eggs that we knew were from certain hens and not a one of them was fertile while there were some eggs from other hens where each and every one of them developed into chicks after we started incubating them. There was no difference in taste or texture between the eggs that were laid by the rooster's favorites and those that were laid by the hens that played hard to get.