I am not so sure. I am 51 and menopausal. Yet, I am experiencing the best and most sexually active time of my life. My partner has much to do with that though. His warm emotional affection translates to the desire for physical affection. I think being for the first time in an emotionally and physically secure relationship is also a pretty big reason for my desires. This man is particularly sensitive to my needs and understanding of my mental health. He is more than simply being my best friend. He does a great deal to show his own affection and I respond in kind. We don't go anywhere without holding hands for example.

Have you done a self-check? Does she have needs which perhaps aren't being met? Does she have reason to feel insecure about anything? How is her mood these days; depressive? anxious? Does she perhaps have physical impediements to sexual activity. What about her self-esteem and sense of worth; do these need encouragement? What kind of together time do the two of you spend?

There are numerous reasons then I would look to sorting out before concluding it is hormonal. It might very well be but I would eliminate the more obvious factors before jumping to conclusions.

Have you talked to her? Does she indicate she is troubled with this? encourage her to see her doctor. There are non-synthetic hormone remedies out there that may be of help.