Yes. Long ago during sex a girlfriend slid off me and measured a full ten inches. During foreplay--especially extended foreplay--she often commented on how much bigger I got.
OMG you are enormous! There was noticeably more girth and my balls which normally dangle and swing when I'm erect were drawn up tight.
I think she was pleased she made me bigger, lol.
Smallest I've ever measured erect is 8.5 inches. My "standard" erection is nine.
She wasn't the first to notice but she was the first to measure. A premed bio major like me she was curious to measure things, lol. Other partners have noticed and commented on it over the years. I have a theory that some women release pheromones that make me bigger perhaps because they are ovulating or about to.
Several women have told me they notice that their hubbies sometimes have bigger chubbies.