We're thinking about having another child, but our first is around 1 and still breastfeeding.  For various reasons I hear this can prevent/hinder pregnancy.

Any thoughts?  Also, someone commented here recently about a 3-4 year separation between siblings as the natural gap; a link to info would be appreciated, cheers!

We breastfed our first child to about 10 months, and kept her on stored pumped breast milk to 12 months.  We only stopped because we were required to stop in order to start the IVF process for our second child, and since my wife was in her late 30s and we wanted a total of 3 chidren, we felt pressed for time.  Even then, had we known that the second child would take only 1 three month IVF cycle rather than the 4 cycles and more than a year that the first child took, we would probably have delayed by six months or so.

My wife is still breastfeeding our second child, the paleo since implantation one, at 16 months.  My wife also just got pregnant naturally, so paleo seems to have cured her infertility.  And, she is 40.  So you don't need to wean in order to have a child, and it's possible that women on the paleo diet have a little extra time.

I think it's best to wait for the child to wean naturally.  I think this most likely happens when the child has enough teeth to eat enough solids, and as Jean says, the right kinds of solids, namely meat with fat.  Our children get their teeth late - probably my Asian genes - and our second child has all his incisors but no other teeth yet, so he can eat fruit but can't really chew meat yet.  Jean, I'm thinking your kids probably had more than just incisors when they weaned?

With respect to child spacing, I posted some statistics on hunter gatherers - 38 months average spacing for the Ache and 48 months average spacing for the San - here:

http://cavemanforum.com/research/data-on-hunter-gatherers-ache-hadza-!kung-etc/

That post cites the source but doesn't provide a link; you could probably google on the article name and authors to find it if the article is on the web.  Note that the San live on marginal land, while the Ache at the time of the study lived in undisturbed rain forest, which might explain why the Ache were able to have children on a shorter spacing.

I have seen some articles that cite a neanderthal birth spacing of 3-4 years, but I don't have cites or links at my fingertips.

Based on my personal experience, I definitely recommend a spacing of at least 3 years if your wife's age and your family plans permit.  Basically, prior to 3 years, an older sibling is a potential threat to a younger sibling, and having them both greatly increases the adult supervisory burden, because you have to have an eye on them at all times.  After 3 years or so, children are mature enough to understand better about not hurting others, and also better understand things like not using a choke hold to "help" retrieve a younger child who is straying.

To put it another way, our two children at a 20 month spacing seem like much more than twice as much work as one child was, as we have to supervise their interaction as well as supervising both children.  I'm convinced that if we'd waited for, say, a 40 month spacing, our older child would actually have been able to help significantly instead of being a hindrance - she already wants to help, she just doesn't know how yet - and the two children would have been significantly less than twice the work for us parents, instead of more.

Of course, I don't know how old you and your wife are and how many children you want.  And of course, there can be some economic advantages to spacing the children more closely since you'll have fewer years with a preschooler in the house.  While 3-4 years is probably ideal from a paleo standpoint, there may be modern considerations that dictate otherwise.

Any thoughts?  Also, someone commented here recently about a 3-4 year separation between siblings as the natural gap; a link to info would be appreciated, cheers!

The combination of calorie restriction and on-demand nursing can suppress ovulation, but if you're wife's body is getting enough nutrients to nurse and support ovulation/pregnancy, she may be able to do both.  From what I understand, the "birth control" from nursing is somewhat limited for many mothers when there is a surplus of food available.

Here's the abstract for one study on the !Kung that gives the 4-year number.  If you google "interbirth intervals hunter gatherer" you'll get a fair number of hits with google scholar. 

http://www.sciencedirect.com/science/article/pii/0162309586900026

In the book Nisa: The Life and Words of a !Kung Woman, Marjorie Shostak mentions something about !Kung mothers sometimes getting pregnant and nursing the older child through the pregnancy. 

My experience with spacing has been as a sibling, not as a mother.  My younger brother and I are less than two years apart in age, and fought non-stop growing up, although we get along great now.  Our younger sister was intentionally spaced out 4 years after my brother, and we never fought with her.  Both of us adored her and loved "helping" our parents with the baby.

  My wife also just got pregnant naturally, so paleo seems to have cured her infertility

congratulations Warren!

My sister and I were 22 months apart and just 1 year different in school (I skipped a grade).  I think it's a bit too close - she literally wanted to kill me when I was born, and my mother had to deal with a newborn and a toddler whose tantrums were only made worse by having a lot of adult attention go to her new sibling.  When we were growing up we were very close but fought, and being so close in school years made things very competitive.  I always felt that whatever I did/achieved was less significant because often she'd already done it the year before, she probably felt threatened by a sibling just one year below her very slightly out-performed her academically and whom she thought had things easier.  By the time I was 18 and she was 20, people who met us assumed that I was the older sibling.  To this day she remains very sensitive to any kind of perceived favouritism.

My two aunts are also less than 2 years in age, were competitive with each other when young and now don't speak as adults.

I think 2.5-3 years gives kids a bit more chance to be become more independent and grow into themselves a bit, meaning that they handle it better when a sibling comes along.

Can't get pregnant while breastfeeding? False.

Natural gap? That's how long it takes to get pregnant again (for some a while for others almost immediately)

If you have control of when next pregnancy occurs, then for goodness sake do it when it suits you and not when some 'authority' says you should. One of the very best things about not actually being paleolithic or natural is that we have birth control. It is you two who will lose sleep, juggle needs and finances and take the responsibility for parenting in your own style. I know you want the best for your children but good enough parenting is good enough (and probably more beneficial anyway).

If you have two placid or easy personality types then one after another is great. If you have kids who are more challenging then sometimes forever is too soon.

BTW - don't go thinking that challenging personality types are in any way related to diet or anything else - sometimes it's a family trait, sometimes high intelligence, sometimes an individual personality (like strong willed etc) and sometimes it's a fragile personality or developmental disorder or bad luck or ill health. Sometimes a challenging child is going to be the cleverest, most creative and most original thinker and sometimes a challenging child is going to need every ounce of protection, patience and perseverance you have. So for goodness sake, no matter what kind of child you have, have him or her when it's best for you. The rest will work itself out.

I have 3 grown up (lol) children - 28, 25 and 22.

and congrats Warren!!

congratulations Warren!

Thanks!  However, it's still very early.  As I mentioned in another thread, I figure there's about a 50/50 chance of its sticking.

It makes me wonder when children became so "delicate". Looking at my family tree, five or six generations ago most of my forebears had 10 or more children, usually within 20 years. I don't have lots of family stories of them suffering terrible psychological damage as a result. What happened?

lol... well I guess it is all relative. Having a sibling close in age may cause the elder sibling to develop some attention seeking tendencies but then again these would not be called psychopathic tendencies which one could say do indicate "serious psychological damage". 

One of the problems with western society is that it is modeled to work around male fertility as opposed to female fertility where really it should be the other way round as it is female fertility that has the timer. But then it is difficult to work out how to ensure all women have been educated well and are in a stable financial and familial situation in which they can raise children without having to work by the time they are in their early twenties. I have managed to do this as I am 23 with my first baby but am definitely an exception.

Thus, like you say, most people in western culture choose to have children when they can afford it which I am not debating is not sensible. Of course I do not think that it is the parents fault if they are infertile either. That is very sad and it is a blessing if they manage to have a child. I still question in both cases however whether this justifies having more than one child in a shorter space of time if you know it is risking affecting the other child's psychological development negatively.