Is it OK for a girl to moan during sex?

Apparently I moan a little during the more pleasurable moments of sex, but my boyfriend told me he finds it unattractive because it seems fake. Thing is, it's not actually fake, I didn't even realize I did it until he pointed it out :( and now I'm really conscious of making noises when we are in bed together, even though sometimes I feel like I want to, it makes the experience more relaxing for me when I can just be myself and express how he's making me feel? It's not like I scream or anything, I'm pretty quiet...