In case you ever wondered.

Scientists have more data and another hypothesis as to why female primates make noise during sex:

Female chimps often cry out during sex to attract nearby males, but they keep quiet when other females are around so they don't alert their competition, a new study finds.

The function of copulation calls made by female primates (a group that includes lemurs, monkeys, and apes, such as humans and chimpanzees, our closest relatives) has been debated for years.

Interesting... so if your female partner is noisy during sex it means she wants more males to join in the fun. I'll bet that is going to make for some interesting pillow talk.