Allow me to introduce you to LadyComp, my best friend for the past 3 years and 5 months. It is a birth control device which doubles as a pleasant sounding (and cool looking) alarm clock. It is 99.3% accurate, completely natural, and it is perfect for me! By taking your waking temperature (sticking the thermometer under your tongue) every morning for 30 seconds, LadyComp's computer knows when you're fertile and when you're not. Each morning, you're told if it's a red day (no sex if you're looking to avoid a baby), a yellow day (proceed with caution - I know a very cute baby who arrived because of yellow-day sex) or a green day (go ahead without any other protection because you're infertile!) It's much more reliable than traditional charting, and couldn't be easier to use. What's also very cool about it is that if you are interested in becoming a parent, you can just switch things up and know that red days are when you're most likely to conceive. There's even flashing red for ovulation. There is also a product called BabyComp which is specifically designed for people who want to conceive. (As far as I can tell, they took LadyComp and added a few lights.) And they now have something called a Pearly, which is a mini LadyComp that runs on a battery (great if you're travelling a lot). LadyComp does come with a battery pack, but the battery pack is not recommended for long-term use. Good for camping, though. I can't say enough good things about it! I don't have to take the Pill (I have many issues with the Pill) so my cycles are natural rather than synthetic ones, and it's just amazing to know what's going on with my body.