From some casual research, it’s come to my attention that some forms of radiation therapy (for cancer, etc.) carry the risk of causing permanent infertility in the patient.
That reminded me of something, slightly disturbing; that the Nazis had, from what I remember, actually did some sterilization experiments along those lines, during the war. Of course, the Nazis did a lot of biomedical research, much of it unethical, and/or of such sloppy methodology that it’s scientifically useless.
It got me wondering, though…can you use radiation to cause permanent infertility in a human, without killing them or causing a grave health risk? Say, if you’re aiming for a procedure with comparable failure and mortality rates as surgical sterilization. (Okay, say…the roughly the same failure rate as a vasectomy, and roughly the same mortality rate as a tubal ligation, at most.)
As I recall from some research on sterilization before I had the surgery, the medical definition of sterility in men involves a spern count below a certain level. So a sterile man might still produce active, viable sperm, but the odds of causing an impregnation are very small. Even after the surgery I was still producing healthy sperm, it just wasn’t getting where it could work as intended.
I never researched the definition for women. I would guess the definition might be considerably wider, given that there are simply so mant more things that could go wrong. There could be some form of barrier to sperm OR egg, or something that would prevent an egg from attaching in the uterus, or who knows what else? Well, I’m sure someone does, but not me.
So a questio for you is, how sterile is sterile enough?
I find it difficult to imagine that your question has been scientifically tested to determine an answer with any degree of certainty, and research is unlikely to be attempted due to potential risks of birth defects for those infants conceived during testing on the one hand, the possibility of damage to a parent on the other, and the relative simplicity and safety of other forms of contraceptives.
I do know that it can be very difficult to kill cancer cells without damaging healthy surrounding tissue. Similarly, I would expect it to be equally difficult to kill one small group of healthy cells without damaging other healthy cells around them.