Folks, I may have posted the gist of this as an annotation elsewhere on the HalfBakery, but I do think it needs to be its own topic.
The goal is to devise ways to completely block any chance that sperm and egg can meet. The method should be reasonably simple, perfectly reliable, and un-do-able only when the "blocked" person wants to become unblocked. There should be a method that works for either sex.
Here are my suggestions:
FOR THE MEN: Background info: The vas deferens is a thin duct that carries sperm from the testicles to the "biopump" at the urethra. The first vasectomies cut this duct, and tied both of the cut ends, so sperm could neither get out at the cut, nor get in toward the urethra. However, the testicles constantly generate sperm, and pressure builds up unitl the the first part of the vas deferens painfully burst. Nowadays they leave that end untied, and let the body's immune system gobble up the sperm that drip into the main body cavity. A vasectomy is not an easily reversible technique, because the duct is so tiny it is extremely difficult to sew back together.
I once read that some doctor tried installing valves in the vas deferens. Then you could simply open or shut the flow of sperm as desried. However, when shut the pressure-buildup of sperm still causes the same problems as a tied-off duct. No good.
HOWEVER: Just change the design of the valve to a Y shape! Sperm flows in at the base of the Y, and the valve either directs it "out" into the main body cavity, just like a vasectomy, or the valve reconnects the vas deferens, thus restoring fertility.
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FOR THE WOMEN Background info: The fallopian tubes carry eggs from the ovaries to the uterus. Various sexually transmitted diseases are known to sometimes cause sterility in women by infecting the fallopian tubes, resulting in the formation of scar tissue that blocks the tubes. In a way, it is OK for these tubes to be blocked, if a woman WANTS to be sterile, because they are both larger-diameter than the vas deferens in men, and the number of eggs that get backed-up behind the blockage can never be more than a few hundred. Women are born with a fixed number of eggs, so no "pressure buildup" is possible here.
For women who have suffered disease-caused steriltiy, and don't like it, one hopeful technique exists. A fiber-optic line is passed through vagina, cervix, and uterus, into the fallopian tubes. A laser beam is use to burn the scar tissue away, and reopen the tubes. I am unsure of the success rate of that procedure, but I will assume that the art will improve with time.
Suggestion: For a woman who wants to be sterilized, deliberately block the fallopian tubes by injecting a blob of Super-Glue. This stuff is known to be compatible with the body tissues of most people (surgeons sometimes use it when putting various body parts back together). Super-glue is water-activated, so as soon as it is injected, a good blockage should form. Over the long term, some scar tissue formation may also occur. To reverse, see preceding paragraph.-- Vernon, Apr 29 2002 Sterilization http://www.rho.org/...t-sterilization.htmBrief overview/summary (source of my statistics). [pottedstu, Apr 29 2002, last modified Oct 21 2004] Contraceptive implants http://www.fpa.org....ontracep/conimp.htmBritish Family Planning Association website. [pottedstu, Apr 29 2002, last modified Oct 21 2004] Vasectomy sans scalpel http://www.malecont...ds/risug_frame.htmlInject a material into the vas deferens that kills the sperm as they pass through. [Maurkov, Aug 27 2002, last modified Oct 21 2004] Intra vas device http://en.wikipedia...ki/Intra_vas_deviceAlmost ready to come out of the oven. See links at the bottom for more. [omegatron, Jun 22 2005] Trojan brand superglue.-- bristolz, Apr 29 2002 Uh-Oh, it's stuck. When is your husband due home?-- thumbwax, Apr 29 2002 A couple of points here.
//However, the testicles constantly generate sperm, and pressure builds up unitl the the first part of the vas deferens painfully burst.//
What happens to the spermatozoa which are produced in the testicles but cannot escape because of the cut vas? They cease to be produced after a short time, so there need be no anxiety for the vas or testicles to become bloated with sperms.
//and the number of eggs that get backed-up behind the blockage can never be more than a few hundred. Women are born with a fixed number of eggs, so no "pressure buildup" is possible here.//
Only one egg is released each month,and once it migrates onto the oviduct it is destroyed by other body cells. No question of even one egg building up.
Also, only one woman in five who has a procedure to unblock her tubes becomes pregnant and later delivers a live healthy baby.-- Helium, Apr 29 2002 I think Vernon is mistaken if he believes these sterilization methods are inherently 100% certain. Tubal occlusion in women has a 0.2% - 0.5% failure rate in the first year; vasectomies have around a 0.1% failure rate.
Perhaps a better bet for long-term birth control are hormonal contraceptive devices inserted under the woman's skin. These can provide protection for up 5 years, and be removed at any time. However there are health risks associated; but in time as with the contraceptive pill it is likely that these will become safer and more advanced.-- pottedstu, Apr 29 2002 Oddly, the subdural contraceptives that were on the market, and much bandied about 5-6 years ago, don't seem to tbe on the market anymore.-- bristolz, Apr 29 2002 UnaBubba and thumbwax, if you both honestly think that your peckers are long enough to reach the glue in the fallopian tube, I think you're both terribly big headed.-- Helium, Apr 29 2002 Norplant implants were taken off the market in some areas, although there doesn't seem to be any specific problem that led to that decision. However, it's possible that the company became aware of health risks it doesn't want to reveal. There were problems with them being inserted by doctors and nurses not trained to do so. There is another brand that's still in use, Implanon.
Intrauterine devices (coils) do a similar job in providing long-term contraception, but have a failure rate of around 1%, which is significantly higher than the contraceptive pill.
And of course none of these provide protection against sexually transmitted diseases.-- pottedstu, Apr 29 2002 I'm greatly relieved to hear it UB, but I believe I already know the answer, after all, you're an Aussie.-- Helium, Apr 29 2002 Australians (in my limited experience) are never too concerned about driving particularly flash cars, if that helps you, blissmiss.-- sappho, Apr 29 2002 thumbwax and UnaBubba, while what you posted is humorous, you both should know that Super-Glue will only exist in the sticky-let's-get-the-parts-together-NOW state for a few seconds. A small blob is only going to cause X amount of tissue to become glued together, after which nothing else will become glued to the blob.
Helium, in the main idea, where I described a burst vas in two places, the reason I wrote that was because I had read it on separate occasions (one regarding vasectomies, and one regarding valves). I'd like more data behind your statement that a backup of sperm causes production to shut down. OTHER things I had read is that when the storage place at the urethra is full, the overflow seeps into the bladder and goes out with ordinary urination (instead of causing production to halt).
Next, the failure rate for vasectomies is associated with how well one end of the cut vas deferens remains tied off. If the tie becomes untied, then the duct reopens and sperm can get through once again. (SOME failures are due to impatience on the part of the men, who are supposed to wait a week after having the operation, before having otherwise-unprotected sex. Sperm already "in the pipeline" has to be allowed to clear out, before the guy starts to shoot blanks.) I can see that if valves are installed, the equivalent uncertainty comes from how well the ducts are attached to the valves. Perhaps they can be glued on?
About women's eggs backing up, yes I know that normally they disintegrate if not fertilized. However, behind a blocked fallopian tube, what happens to the material that made up a now-disintegrated egg? My worst-case assumption is that the debris of a few hundred eggs piles up, harmlessly.
Part of the reason for the low success rate in unblocking disease-scarred fallopian tubes is the fact that the ordinary course of a disease is to infect the whole length of the tubes, causing equivalent amounts of scarring. My suggestion that a small but thorough blockage be created, via a blob of glue, should lead to a much greater blockage-removal success rate.
pottedstu, yes, I know that there is no such thing as a 100% perfect birth control technique. Just ask the Virgin Mary! We can only do as best we can.-- Vernon, Apr 29 2002 Just in quick reading, I think (as is most often the case) that of the two procedures/follow-up procedures that Vernon recommends, the most invasive is that suggested for the woman.
Then, pottedstu, says //Perhaps a better bet for long-term birth control are hormonal contraceptive devices inserted under the woman's skin// again, invading the woman and putting her hormones out of "natural" levels.
I have often believed that the issue of birth control should be dealt with by the man. How about a hormonal contraceptive inserted under the man's skin? Or a daily pill to stop the production of sperm? Not surprising, most men cringe at the thought whereas they think nothing of subjecting their wives and girlfriends to such things....
I think the key is some sort of vasectomy for a man that can more easily be reversed when the time is "right". After all, unlike tubal surgeries on women, vasectomies are a 20 minute procedure in the doctor's office.....-- runforrestrun, Apr 29 2002 runforrestrun, it appears that the definition of "invasive" is up for grabs. For women, I was trying to imply that the Super-Glue could be introduced in the same manner as was described for a laser beam. Sorry I wasn't specific. Meanwhle, a vasectomy or a valve job for men requires some surgery, even if minor. Which way is thus more invasive? (Personally, I think they are roughly equivalent -- the woman will be uncomfortable but not cut open like the man.)
Next, I can agree with you that men deserve to do their fair contraceptive share. I think I wouldn't mind having those Y-shaped valves installed, simply because reversibility is fairly easy. HOWEVER, in the larger sense, you are missing a significant and unfortunate biological fact.
Consider a group of 100 men and 100 women. Pay no attention to their escapades; all that matters here are the consequences. How many pregnancies are likely if no birth control is used? Close to 100, probably, right? OK, sterilize 99 men and ask the same question. 100 pregnancies are still possible! But sterilize 99 women, and only 1 pregnancy becomes possible. So, regardless of the fact that men should be more responsible than they typically are, the bottom line is that actual numbers of pregnancies depend more on the number of women being responsible, one way or another. It is unfortunate for the women, but it is true all the same.-- Vernon, Apr 30 2002 Vernon, before annotating, I checked my facts with 'Everywoman, A Gynocological Guide for Life' by Derek Llewellyn-Jones OBE, MD, MAO, FRACOG who also writes obstetrics, gynocology and human reproduction books for medical students. This book also contains several chapters on men's bits and their function.
It's possible that it doesn't take into account the earlier vascectomy method, but it does make it clear that sperm production will cease.
Any egg remains would be absorbed by the body. Remember, the body can absorb an entire fetus at an early stage.
As for tubes, the more common method now is not to tie the tubes but to put clips on them. This means only a very small piece of the tube is damaged. So, in the case of reversal, this small piece can cut out and the two ends joined back together.
With a good surgeon, the success rate for reversal of clipped tubes is 80%. (This statistic provided by my local medical center). I think, at best, this would be the rate you would be looking at for your hoo hoo glue tubes, assuming that the damaged area is removed.-- Helium, Apr 30 2002 Helium, it seems we have a conflict of data sources. I know of no good way to resolve the issue. To be continued, I suppose....
Next, yes, tubal ligations are done these days in a way that makes it easier to undo them. Both procedures count as significant surgery, however, which hardly qualifies as convenient. The idea here concerns something that needs to be both simple and reliable. I do not claim to have succeeded at that; it is a half-baked idea. And so it belongs here.-- Vernon, Apr 30 2002 oh for goodness sake. There are other things to do with your time than having sex. Go climb a mountain. That's a 100% effective birth control method. Read a book. Look after someone else's kids. And Vernon, the Virgin Mary comment wasn't funny.-- sappho, Apr 30 2002 Sappho: If you're annoyed by people thinking about sex, what the heck are you doing reading ideas in the Health: Birth Control category???-- magnificat, Apr 30 2002 If sappho really believes that birth control and over-population are a tiny problem, I wonder what he/she considers a major problem. They have importance ranging from the ability of a woman to control her own life, to the future of the entire ecosystem. Sappho's ideas seem to revolve around vital social issues like going out without an umbrella or buying ill-fitting clothes.-- pottedstu, Apr 30 2002 Hm. That was somewhat unnecessarily harsh, I think, 'stu.
As far as I am aware, women can and do control their own lives currently. What does birth control have to do with it? If a person has sex, they know there is a risk of pregnancy/disease/etc. They control whether they have sex (obviously not including rape here). Ergo, they control whether they expose themselves to those risks.-- waugsqueke, Apr 30 2002 Harsh? If sappho's compaining about people posting trivial ideas, it's surely relevant to compare sappho's own ideas.
And surely ensuring women can have sex and not have children is giving them a far greater amount of freedom than ensuring the only method of avoiding children is to not have sex. While I recognise that people may be arguing against this idea based on a religious or moral conviction that the only legitimate purpose of sex is for procreation, even the Vatican now recognises that sex is an important part of marriage as an expression of love even aside from its role in reproduction.
I'll leave the issue of whether women can and do control their own lives currently to others more qualified than I, but I could doubtless come up with many citations from the developed and developing world about the positive value of family planning.-- pottedstu, Apr 30 2002 //nothing to see here//
My point exactly.
If you'd taken into consideration the fact that I'm a NZer UB, I'm sure you would have known which way to take it. Eheh....*ducks*-- Helium, Apr 30 2002 sappho, my comment about the Virgin Mary was simply to point out that if you believe that story, then you CANNOT also believe that abstinence is a 100% effective birth control procedure. Look at it this way: If God wants some women to be pregnant, probably not even abortion will be able to interfere (mere humans versus infinite power? Come on!). But if God does not have such a want, then it is up to us to do our best, one way or another, to ensure that the natural biological drive to reproduce doesn't result in a Malthusian Catastrophe.
waugsqueke, you are somewhat mistaken about the freedom that women have to decide about having kids. It is mostly true only in "developed" nations. Much of the world still regards women as suitable for nothing except sex, cooking, sex, cleaning, sex, babies, and more sex. I think that there needs to be a revolution in women's conciousness. One mad notion that I had read about (and actually hope is true), concerns the occasional woman who gets pregnant by some guy she discovers she doesn't like (rapists, usually), and then becomes so enraged, she POSITIVELY ABSOLUTELY REFUSES to bear "that man's child" -- and then she miscarries. If actually true, then I think women should be trained to be able to conciously invoke miscarriage by sheer willpower. Then men will HAVE to treat women nice, if those men are ever going to have offspring!-- Vernon, May 01 2002 I did a bit of research on this recently. I wasn't excited about hormonal birth control while my wife was breastfeeding. We planned to have a second, so the permanent options were out. In monogamous relationships, condoms leave a lot to be desired. RISUG looks great (see link). I hope it passes clinical trials.-- Maurkov, Aug 27 2002 I still don't understand the problem with valves. That really doesn't seem beyond current medical science...-- Skullhead, Aug 12 2003 Maurkov, excellent link!
Skullhead, the original valves were inlet-on/off-outlet only. Nobody to my knowledge is making valves suitable for the vas deferens with one inlet and two outlets.-- Vernon, Aug 26 2003 RISUG does sound awesome for those of us in monogamous relationships. I worry about my girlfriend taking hormone pills that mess with her system, and I think it is bulls**t that it is entirely the woman's responsibility in these things.
However, it will never pass clinical trials, because there is no money in it. The doctor in India who came up with the stuff says it would cost about $20 per injection, and each injection lasts as long as 10 years with no maintenance (unless you want to pay another $20 and use the reversal injection which returns you to normal fertility). How does that make sense for a medical company to foot the research bills when they can charge a woman $30 per month, every month for those same ten years? $3600 vs. $40. Hmmm... And when it costs at least $20 million up front to bring a new drug to the american public... Sorry, but the hormone pill is HUGE business, and there is no way the drug companies will pay money to that cash cow slip away.-- aluxeterna, Feb 19 2004 random, halfbakery