I have been an advocate of pull-out for years. Between the time my wife and I used it and my previous girlfriend did, I have over six years of non-failure with PO, which at 78% success rate each year, is .78^6 or 22% chance of having six successive years of using pullout without a failure. (for those who want to use PO as a long term method, ten years of 78% success rate is 8.3% success rate per decade, not good)
I will note that when my wife and I decided to "stop avoiding getting pregnant" (which is the same thing as trying to get pregnant from a practical perspective) she was knocked up after her first ovulation, so there wasn't any infertility at play in my six years of pull-out.
However, I will add two big caveats to this anecdote:
Successful PO has a lot to do with the individual. Maybe I'm really good a knowing when to pullout, maybe there is absolutely zero sperm in my pre-ejaculate. But not everyone will have such characteristics. It would be nice to have a way to test if you are good at it that didn't have major consequences.
Also, my wife and I were using PO in conjunction with
basal temperature rhythm method which is basically tracking vaginal body temperature as a means of predicting ovulation, not a perfect science and we ignored the it most of the time (she was doing it as a body awareness exercise).
I will also note that after our first was born and before we were ready for #2, we used condoms. While pullout was successful for so long, at the time, having a kid would not have been the end of the world, but in no way did we want 2 under 2.
Vasectomy was free with insurance and I have a week until I test for effectiveness. Hopefully we're a week away from free, zero-waste sex.
Also, our biggest reason for not using an IUD between #1 and #2, was the terrible, yet rare consequences if there is a pregnancy while using one, which scared my wife away immediately.
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An after thought, I'm not sure the capital and operating expenses involved, but there is a device that people having trouble conceiving use to pinpoint ovulation (which uses hormone levels in urine). These can theorectically be used to avoid the 3-4 days per cycle when pregnancy can occur. Amortizing the cost of the device over it's lifetime as well as the cost of consumables and comparing that to the cost of condoms, it might be a low cost method. Though the average number of times one has sex per week/month/year will directly impact the economics. If you're a birthdays and anniversaries couple, condoms are pretty cheap; if you're everyday and twice on Saturdays, condoms would be pricey.