There's numerous mobile phone apps that do this for women. https://itunes.apple.com/us/app/pink-pad-period-tracker-free... I thought to make one for men for just the reasons you described but it seemed a little too.. unethical.

Especially since women's vocal range is affected by their cycle. I thought to use DSP to help determine their cycle and facilitate pregnancy or help avoid it. It turns out getting the proper audio baseline for the vocal range of women is tough and they'd be saying weird words into their phone daily.