Right - we know that childbirth is pretty painful, right? But shouldn’t evolution have erased this little design flaw? I would think that whilst painful labour doesn’t act as a huge brake on propogation of the species, things would sure be better if the whole thing was painless.
I might guess that perhaps a painful labour puts women off sex long enough to give the new-born a chance to establish itself before another baby comes along. However, as far as I know, animals don’t go through agony when giving birth. Baby animals just seem to “plop out” and that’s that, which would seem to suggest that pain-free births are a fine idea, i.e. that pain does not give any real advantage.
So, as far as I can tell, there are two possible reasons for painful labour:
Women are having us on. All that hollering is just a cunning ploy to make men feel guilty. Every time the man pops out for a cigar or to check on the football results, the woman in labour has a right laugh with the nurses about how stupid men are to fall for this old chestnut.
Women are lazy evolvers. Rather than going through the process of evolution in order to remove pain from childbirth, women have preferred to sit around all day with peanut butter and coal with jellied eels, waiting for the men to invent a painkiller for them.
Obviously I will never know the truth unless I go through an advanced sex-change operation and have kids myself, but there is only so much I am willing to do in the name of knowledge. I am therefore hoping that someone can enlighten me.
James.
[sub]PS - To those dashing off to the BBQ Pit: [/sub]
[sub]PPS - Serious question, though[/sub]
I’m sure a medical type will drop in at some point, but I understood that the limiting factor is the size of the infant’s head (= braincase), and that we’ve gone as far as we can in that direction. In order to go further we’ve evolved the capability for an infant’s head/brain to keep growing in the early stages of youth, which I understand to be unique to humans.
Also, I read somewhere that it’s the hip/waist ratio which is a general factor in female attractiveness… (i.e. medium-large hips + small waist). YMMV.
That’s purly a cultural thing. For example there’s a group somewhere in Africa where the women wear clothes that give them the appearance of having larger hips. This is a society where women typically have 8 or more children in their life time.
One of the reasons childbirth is more difficult for us is because we stand upright. I don’t think any other primate has the same difficulty as we do when it comes to giving birth.
Ahh… I can see why walking upright would give humans grief when giving birth. However, this still leads back to the question: why haven’t changes occurred to make giving birth better compatible with walking upright?
I guess because there’s no reason to change. Despite the difficulties people are still being born and living long enough to reproduce. Apparantly the difficulty in giving birth hasn’t had a negative affect on the survivability of the species.
But we’ve been walking upright for how long? Surely over this period some change ought to have taken place?
A pain free birth would not give a significant advantage, but it must give a slight advantage, in that women would be more likely to have more children (even if only very slightly). Over a long period of time, this small advantage ought to become the dominant characteristic - that is what evolution is all about, is it not?
On the other hand, of course, if there was absolutely no advantage to pain-free birth, then, as you say, it would not evolve as a dominant characteristic.
I just want to point out that there probably is a evulutionalry reason why women develop fat deposits on thier hips and men don’t: it makes them look as if they would have an easier time giving birth. However, there is no reall way to tell from looking at a woman if it is hre hips or the tissue over hips that are wide. But women with wide hips look more fertile, so they got more matres, yaddie-yaddie-ya.
An exacyt parallel to this is the penis: Gorillas have two inch penises that work just fine. The human penis has grown over the decades not because a man with a bigger penis is any more fertile, but because he looks like he is.
Baby animals just seem to “plop out” and that’s that, which would seem to suggest that pain-free births are a fine idea, i.e. that pain does not give any real advantage.
Why can’t human animals do this? This question was exactly what prompted a young obstetrician named Dr. Robert Bradley to experiment with different techniques and, eventually, come up with his method of natural childbirth. He looked at the women in the maternity wards, in horrible pain or drugged into insensibility and compared them to the animals he’d seen giving birth on the farm on which he grew up. He noted what it was the animals seemed to want and tried to create those same conditions for his patients.
What do animals do? In early labor, they tend to walk around a lot. (In humans, walking greatly reduces the length of labor.) When labor gets serious, they go off to a nest they have made for themselves. A pet dog might make a nest of dirty laundry in the bottom of a closet. A wild animal might turn circles in the soft earth until it has formed a hollowed out space. In any case, they make themselves a place that is comfortable. They want to be alone and will snap at anyone who disturbs them. In fact, sufficiently disturbing an animal in labor will cause its labor to stop. They lie down, eyes closed as if asleep and breathe deeply and slowly. They don’t fight against their labor, but instead allow their bodies to work unhindered.
Dr. Bradley’s early experiments merely consisted of teaching his patients how to consciously relax their bodies and giving them the space to labor in undisturbed. These experiments were very succesful. His patients were, for the most part, able to give birth unassisted and reported much less pain.
Why do most humans need to be taught how to do this? We think too much. We have the instinctual abilities that other animals have, but they are buried under our intellectual processes. Because we walk upright and give birth to babies with very large heads, we will never give birth with quite the ease of other mammals. But we can learn to make it easier.
Please repost this question ~25 million years after upright posture, OK?
[sup][sub]and you can’t count years where the medical establishment intervenes and preserves lines in which the females can’t give natural birth [/sup][/sub]
All the time in the world doesn’t matter a bit if there’s no biological need to evolve. If painfull childbirth begins to have a direct correlation with the death of the child, well, then, you might start seeing evolution at work.
Nowhere in the rules does it say that life shouldn’t hurt -
Don’t get fooled by the common misconception that somehow evolution is some kind of tool that a lifeform uses to adapt, like some kind of WonderTwin power. We notice evolution in a species only when some physical characteristic of the animal/plant has an effect on the species life-or-death ability to live to reproduce.
Any situation that is not dire enough to create a life-or-death struggle is not serious enough to cull out the genetically less fit members of the species.
IIRC, our Neanderthol … um… relatives (?) ran into a problem in that the brain-case of their children gradually increased until it was LARGER than the aperture in the pelvis through which it was supposed to pass. Caesarian Sections not being what they are today, Neanderthols ceased to exist.
Also, our better nutrition has not helped. Babies are bigger now in the First world.
I had this thought after giving birth to my daughter. Had I been a hunter/gatherer on the plains - my last three months would have had me lion food. Then there is the 9 1/2 hours of labor - lion food again, and the three-four weeks of limited mobility - lion food.
Trust me though - we aren’t faking it. Although something like 5-10% of women report no pain with childbirth (not me - I would have ripped my own face off) and I think pain is very varible from woman to woman. Something like Bradley can help (doulas are highly recommended amoungst the natural childbirth set as well), but if you have a low pain tolerance and a high pain labor/delivery you will feel pain, and quite a lot of it. Which doesn’t mean you can’t do it without the Nubane (spinal, epidural, etc) - lots of women have for many, many years.
However, childbirth is funny. After you go through it, it is hard to remember the extent of the pain (or the challenges of pregnancy). Few women after a few weeks say “never again.”
But I’ll get right on it with the evolving thing. I’m getting out Microsoft project and figure that, if we throw enough resources at it, we can evolve through this in six weeks.
I am going to give a lovely bit of information with no cite, but I’ll hunt one up as soon as I can:
The pain of childbirth is eased somewhat by the woman’s body’s production of endorphins. That rush of endorphins is supposed to help the mother bond with her child once the baby is born, since the endorphins stay in the bloodstream after the labor has ended. Basically, the woman sees her baby for the first time while still awash with happy chemicals. The endorphin crash that follows may also cause, or contribute to, post-partum depression.
If all that is true, then there could actually be some advantage in the pain of childbirth, since it helps the bonding process early on.
Those endorphins also help with pain relief. From The Birth Book, by William Sears, M.D. and Martha Sears, R.N.:
*Endorphin levels go up during contractions in active labor (especially during the second stage of labor), are highest just after birth, and return to prelabor levels by two weeks postpartum.
Endorphin levels were found to be highest during vaginal deliveries, less high in cesarean births in which the mother had also labored, and lowest in cesarean births performed before mother’s labor had begun.
Endorphin levels are elevated in newborns who had signs of fetal distress during delivery. The baby also receives these natural pain relievers during birth.*
Also, stress hormones (like adrenaline) actually protect the baby during birth. There is a positive correlation between stress hormones and Apgar scores in babies who are moderately asphyxiated during birth. In other words, babies with more stress hormones in their blood tolerated oxygen deprivation better.
So, to answer the OP more directly, we did evolve. We evolved opposable thumbs and we had to stand up on our legs to use them properly. We evolved big brains and needed to grow big heads to fit them in. Because our standing up decreased our pelvic space at the same time our brains were getting increasingly larger, we gave birth to our babies early. (We are far closer to marsupials than other mammals in terms of physical maturation at birth. We give birth and then carry our babies around for a year while other mammal babies walk hours after birth.) Hormones that cause us to fall head over heels in love with our babies (bonding) protect them from neglect. But pain doesn’t kill us, so there is no reason to evolve any remedy.
Maybe it has become less painful. But unless we can reach back several thousand years and grab a sampling of women and find a way to measure their pain against the pain of modern women, there’s no way to know for sure.
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