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June 23[edit]

Ejaculation[edit]

With the help of assisted reproduction technology, theoretically how many kids could a man father from a single ejaculation with the average number of healthy sperm cells. A few hundred thousand kids? Millions? — Preceding unsigned comment added by 62.73.108.80 (talk) 14:22, 23 June 2015 (UTC)[reply]

Semen_analysis#Sperm_count says 20-40 million sperm per milliliter. Ejaculation#Volume gives 0.1-10 mil per ejaculate. So you're looking at 2-400 million sperm per ejaculate. Probably not all of them are completely viable, and in vitro fertilization has a pretty low rate of success if considered on a per-sperm basis. So there's tons of variety and variables (e.g. semen quality), but I think "millions" is a safe answer if you're just thinking of it as a thought experiment (ignoring cost, logistics and other real-world constraints). SemanticMantis (talk) 14:53, 23 June 2015 (UTC)[reply]
But the question assumes the use of existing technology. Let's say there are 300 million spermatozoa in a single ejaculation. Can current technologies divide that into "millions" of microscopic droplets of sperm and then successfully fertilize millions of ova? I doubt that existing technology could handle such tiny amounts of sperm rapidly enough so that most of the spermatozoa wouldn't die before getting near an ovum. Existing technology is optimized for the delivery of sperm from a single ejaculation to a single ovum, and even with a carefully planned effort, I doubt that it would be possible to expand the scale of existing technology beyond dozens of ova and therefore dozens of children. Marco polo (talk) 18:40, 23 June 2015 (UTC)[reply]
Semen_cryopreservation says you'd have at least 21 years to process a sample, possibly much longer. I interpreted the question as primarily being a thought experiment, and more about how many sperm there are per ejaculate, and not about the cost and time necessary to embark on such a project, let alone the specific details of IVF Oocyte_cryopreservation is also technically available, and would help out on the logistics.
Turns out the success rate of live birth from IVF maxes out at around 40%-55%. Reading In_vitro_fertilisation#Egg_and_sperm_preparation in more detail, it looks like they go for ~75k sperm per ovum. I suspect that could probably be reduced considerably, but going down to 1:1 would certainly radically reduce the odds of the overall process working on a per-sperm basis. So if you want a more conservative estimate taking into account more of how IVF is actually done, that puts us at about 1600 live births, figuring 300 million sperm, 75k per ovum, 40% live birth rate. If you want to further refine, they implant about 2 embryos on average, depending on age, but about 1/4 of those result in live birth of twins. So we can multiply 1600X0.75 to get 1200 as a more refined and more conservative estimate. It turns out 167,119 IVF procedures were performed in just the USA in just 2013 [1], so I think we'd have the resources to perform 12k from the same sperm donor if money were no object and we had a few years to work on it. SemanticMantis (talk) 19:25, 23 June 2015 (UTC)[reply]
Maybe I'm missing something, but the group using IVF have selected themselves due to established problems conceiving; surely the number of sperm needed for people with more normal levels of fertility would be lower? Again, not 1:1, but the 75k level would seem to be partly due to problems most folks don't have. Matt Deres (talk) 13:37, 24 June 2015 (UTC)[reply]
Good point. It's all about how much a realistic maximum estimate is wanted, vs. a simplified thought experiment. OP never clarified, but I learned something doing the research above, so I consider it a win :) SemanticMantis (talk) 17:39, 24 June 2015 (UTC)[reply]

Is there any first nations rereserves in Burnaby or East Vancouver In BC[edit]

Please let me know. Venustar84 (talk) 18:06, 23 June 2015 (UTC)[reply]

This is a list of Indian reserves in Canada by population which have a population of 500 or more. A lesser population may have trouble getting reserve statues. So, I don't think we can help you here. It may be simpler for you to contact the Canadian Government. The Freedom of information in Canada should make this easy.--Aspro (talk) 18:27, 23 June 2015 (UTC)[reply]
We actually have a List of Indian reserves in British Columbia. None are listed with a location in Burnaby or East Vancouver. Marco polo (talk) 18:44, 23 June 2015 (UTC)[reply]
Here is a big map of BC reserves (on a Wordpress site at the moment, but originally from a federal government website), that shows a lot of reserves in that general area, although more towards Coquitlam than East Van or Burnaby. The 2015 Metro Vancouver Profile of First Nations also does not list any in Burnaby or East Vancouver. Adam Bishop (talk) 14:32, 24 June 2015 (UTC)[reply]