Vagina is a very elastic passage, you fuck 5 times of 50 times, it doesnot matter much. If the required break is given, vagina feels as it was in the first place.
If you continue fucking everyday, soon you will feel it accomodate very easily, give a break of 15 days, you will know the change. Its snug again. Giving a longer break makes it as new as it was.
I am curious to know the purpose of this question. To me, it seems like you want to have sex with a married woman, whetehr she will be caught by her husband due to your day time activity is your concern I might be wrong, but my reply is, if he is thicker than your's, he wont understand a thing.
The only tie you can feel a big change is when a whole baby comes out, the vaginal muscles doesnot go back to earlier elasticity as it was. Sometimes masturbating with thick object, such as fisting, also causes the same problem.