# Repopulation with 1 woman but multiple sperm donors **URL:** \ **Category:** Factual Questions\ **Created:** [April 2, 2012, 3:11am UTC](https://boards.straightdope.com/t/repopulation-with-1-woman-but-multiple-sperm-donors/617549 "2012-04-02T03:11:40Z")\ **Posts on this page:** 6\ **Page:** 2
**Author:** ![WhyNot](https://avatars.discourse-cdn.com/v4/letter/w/c77e96/32.png) [@WhyNot](https://boards.straightdope.com/u/WhyNot)\ **Post date:** [April 2, 2012, 3:08pm UTC](https://boards.straightdope.com/t/repopulation-with-1-woman-but-multiple-sperm-donors/617549/21 "2012-04-02T15:08:01Z")
> [@pulykamell](#): > > Heck, you don’t even need to look to rural areas. True. My SO is the eldest of 12, all singletons, born in Milwaukee in the 50’s and 60’s and 70’s. And his folks weren’t even Catholic! His mom lived to 87 before small cell lung cancer did her in. Her eyesight was gone years before, but she was constitutionally sound as an ox until the cancer in her late '80s. Of course, as we all know, anecdotes are not the same as data, and Lynn is of course right that having lots of babies in close proximity does increase the chances of something going wrong or mom just wearing out or her fertility taking a nosedive. But the OP doesn’t need to worry about chances - he’s just got one woman to deal with. One women can certainly have babies into the double digits. ---
**Author:** ![septimus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/septimus/32/410_2.png) [@septimus](https://boards.straightdope.com/u/septimus)\ **Post date:** [April 2, 2012, 9:39pm UTC](https://boards.straightdope.com/t/repopulation-with-1-woman-but-multiple-sperm-donors/617549/22 "2012-04-02T21:39:49Z")
[“Wright’s Inbreeding Coefficient”](http://en.wikipedia.org/wiki/Coefficient_of_relationship#Inbreeding_coefficient) is a way to quantify inbreeding. When half-siblings marry, their offspring have coefficient 1/8 (meaning they have 1/8 chance of inheriting the same autosomal allele from their common ancestor). And, in OP’s scenario, the coefficient remains at 1/8 as generations go by. This is logical: For the 3rd generation all 4 gt-grandmothers are the same person; for the 4th generation all 8 gt-gt-grandmothers are the same, etc. > [@bengangmo](#): > > Wouldn’t it be better for the children to mate with the first generation daddies (but not their own fathers)? As **rachelellogram** agrees, this is the optimal solution. Just doing this at generation 2 drops Wright’ coefficient down to 1/32, I think. ---
**Author:** ![Katzenjammer](https://avatars.discourse-cdn.com/v4/letter/k/a6a055/32.png) [@Katzenjammer](https://boards.straightdope.com/u/Katzenjammer)\ **Post date:** [April 2, 2012, 11:40pm UTC](https://boards.straightdope.com/t/repopulation-with-1-woman-but-multiple-sperm-donors/617549/23 "2012-04-02T23:40:05Z")
@Chessic: I found it here: [Inbreeding - Wikipedia](http://en.wikipedia.org/wiki/Inbreeding). @WhyNot: I know, I probably am overthinking it. Was trying to figure out what baby-momma would have to look at in the first few generations she’d be alive - because of course she’d be encouraging breeding early (hairlip issues, malformed children, etc). @Septimus: Thank you! That’s a really good article and I hadn’t come across it just yet. @The general group: I’m also looking at how long sperm can be kept frozen & viable to deal with some of these issues without it becoming too far-fetched. I do appreciate all the input as it helps to flesh some ideas how that I’m unfamiliar with. ---
**Author:** ![The\_Controvert](https://avatars.discourse-cdn.com/v4/letter/t/dec6dc/32.png) [@The\_Controvert](https://boards.straightdope.com/u/The_Controvert)\ **Post date:** [April 3, 2012, 5:20am UTC](https://boards.straightdope.com/t/repopulation-with-1-woman-but-multiple-sperm-donors/617549/24 "2012-04-03T05:20:11Z")
> [@Chessic\_Sense](#): > > What? Why would you kill the baby boys? The female and male populations will be equal as soon as the older generation dies. Then you’d be left with an all-female world. I suggested terminating the first generation males. But maybe “termination” is too unpalatable a term. How about “avoiding”? Filtering out? Selecting against? With this scenario, you have the fate of the entire human race at stake, so you want to make as few mistakes as possible and cost is not an issue. So in-vitro fertilization would almost certainly be demanded and only female embryos should be implanted. Why? Because as it was suggested earlier, the first generation male offspring should not mate at all. If the calamity is not age-selective, there will be plenty of male children who are not related to Eve. So why waste Eve’s precious gestation slots with baby boys that can never mate with their sisters? ---
**Author:** ![Lynn\_Bodoni](https://avatars.discourse-cdn.com/v4/letter/l/e47c2d/32.png) [@Lynn\_Bodoni](https://boards.straightdope.com/u/Lynn_Bodoni)\ **Post date:** [April 3, 2012, 10:28am UTC](https://boards.straightdope.com/t/repopulation-with-1-woman-but-multiple-sperm-donors/617549/25 "2012-04-03T10:28:18Z")
I did a bit of Googling: > **[Is there an ideal time to try for another child?](https://www.mayoclinic.org/healthy-lifestyle/getting-pregnant/in-depth/family-planning/art-20044072)** > > Know the risks of timing pregnancies too close together or too far apart. > [@](#): > > **What are the risks of spacing pregnancies too close together?** > > Limited research suggests that a pregnancy within 12 months of giving birth is associated with an increased risk of: > > [ul] > [li]The placenta partially or completely peeling away from the inner wall of the uterus before delivery (placental abruption)[/li][li]The placenta attaching to the lower part of the uterine wall, partially or totally covering the cervix (placenta previa), in women who previously had a C-section[/li][/ul] > A 2011 study also suggests a link between pregnancy intervals of less than 12 months and autism risk in second-born children. > In addition, a pregnancy within 18 months of giving birth is associated with an increased risk of: > > [ul] > [li]Low birth weight[/li][li]Small size for gestational age[/li][li]Preterm birth[/li][li]Uterine rupture in women who attempt vaginal birth after a C-section (VBAC)[/li][/ul] [http://www.guttmacher.org/pubs/gpr/14/1/gpr140107.html](http://www.guttmacher.org/pubs/gpr/14/1/gpr140107.html) > [@](#): > > The most direct, positive effects of helping women and couples plan the number and timing of their pregnancies and births are those related to improving maternal and child health outcomes. According to U.S. and international studies, a causal link exists between the interpregnancy interval (the time between a birth and a subsequent pregnancy) and three major birth outcomes measures: low birth weight, preterm birth and small size for gestational age. There are also other sites that say that women need some time between pregnancies to rebuild their reserves of iron and folate. So, while it’s POSSIBLE for a woman to have a baby every 10 or 12 months, it’s really not advisable, even if she’s trying to repopulate the planet as the sole female parent. There’s also the issue of one parent taking care of multiple small children. Even if we allow Eve only one year to recover, she’s going to have a toddler in the Terrible Twos when she’s nursing an infant, and both of them in diapers. At least one daddy needs to pitch in and help with the child care, or Eve might very well strangle some of her offspring. It’s true, when kids get older, they CAN pitch in. And let’s note that Michelle Duggar pops out a baby about every 18 months, and then hands it over to an older sibling for most of its day-to-day care. ---
**Author:** ![needscoffee](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/needscoffee/32/1076_2.png) [@needscoffee](https://boards.straightdope.com/u/needscoffee)\ **Post date:** [April 4, 2012, 5:16am UTC](https://boards.straightdope.com/t/repopulation-with-1-woman-but-multiple-sperm-donors/617549/26 "2012-04-04T05:16:14Z")
> [@Lynn\_Bodoni](#): > > I did a bit of Googling: > > [Family planning: Get the facts about pregnancy spacing - Mayo Clinic](http://www.mayoclinic.com/health/family-planning/MY01691) > > [http://www.guttmacher.org/pubs/gpr/14/1/gpr140107.html](http://www.guttmacher.org/pubs/gpr/14/1/gpr140107.html) “Associated with increased risk” could very well be speaking in terms of single-digit increases in percentages. Your cites do not back you up very well. And no one is arguing whether it’s “advisable” or not. [Previous page](https://boards.straightdope.com/t/repopulation-with-1-woman-but-multiple-sperm-donors/617549.md?page=1)