[jaldoretta]

It's a common misconception that the method our app relies on is the same as the rhythm method, which it is NOT. The rhythm method predicts fertility based on cycle length, which is a really BAD idea. The sympto-thermal method pinpoints the fertile window using scientifically-backed signs of fertility.

Planned Parenthood lists an effectiveness of 99.6% (see the "What is the Sympto-thermal Method" section: http://www.plannedparenthood.org/health-topics/birth-control...

[dsr_]

I apologize for conflating the rhythm method and the sympto-thermal method.

It's still a bad idea for most people.

All from the same Planned Parenthood site:

Twenty-four out of every 100 couples who use fertility awareness-based methods each year will have a pregnancy if they don't always use the method correctly or consistently.

whereas:

Vasectomy is the most effective birth control for men. It is nearly 100 percent effective.

and

Less than 1 out of 100 women will get pregnant each year if they use an IUD.

---

I want to control my systems. I have many choices: Puppet, Chef, cfengine, writing my own system... you're offering me a system that requires maintenance every single day, I can't pay someone else to do it for me, and if I screw up, it's 76% likely that I won't have unintended consequences. But there are a bunch of other systems on the market where I configure them once and they work for years without attention, and even systems where I just have to be picky when I'm conducting operations, not every single day.

[wayward]

The 24% failure rate cited by Planned Parenthood includes ALL couples who claimed to be using fertility awareness, from those who had taken classes and were using a modern method, to those who were just guessing. IIRC, over 80% of the couples were not properly trained in a modern method of fertility awareness. Not surprisingly, they had very high pregnancy rates. Someone did the math (can't find the article) and figured untrained users had about a 28% pregnancy rate while trained users had a 7% pregnancy rate. (80 * .28 + 20 * .07) = 23.8 The 7% pregnancy rate is comparable to the real-world use of the Pill.

As for your system analogy, if your automated system was a significant resource hog or ran the risk of corruption of data or crashing the system, would you use it? You focus on efficacy without factoring in side effects.