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Why Is Giving Birth So Hard? Revisiting the 'Obstetrical Dilemma' (theatlantic.com)
60 points by chmaynard on Dec 14, 2017 | hide | past | favorite | 60 comments

Somewhat related, I thought Atul Gawande's take on why C. Sections are so common now was fascinating. It's all in his book "Better: A Surgeon's notes on performance" but I've linked to a summary of the obstetrics section below.

Relevant passage:

"In the 1960s fewer than 5 percent of deliveries were Cesareans and more than 40 percent involved forceps. And those numbers are related. Gawande makes a strong case that in the hands of experts, forceps are safe (according to some research, safer for mothers than Cesareans). But forceps are hard to learn to use properly – a process that can take two years. And if forceps are used by inexpert doctors, the results can be disastrous. Cesareans are easier to master. And this has led hospitals to phase out forceps and, in many cases, do C-sections instead. To discourage the inexpert from using forceps, Gawande says, “obstetrics had to discourage everyone from using them.” This change has come at a cost. Gawande notes that, as straightforward as Cesarean deliveries can be, they can go wrong. The baby can be lacerated. If the head doesn’t come free quickly, the child can asphyxiate."



Even more relevant passage from the article:

"Childbirth is difficult for many reasons, she writes—among them the 19th-century switch from birthing in the upright position, which allows the pelvic girdle to expand in response to contractions, to the supine position (still common among women in the West) which often requires the use of forceps."

There are correct times and places for all tools. But comparing two interventions that both bring risk is an odd way to approach the topic.

> And if forceps are used by inexpert doctors, the results can be disastrous.

"N of one", but I have a cousin who was mentally retarded/disabled during birth when forceps were used on his head.

Obviously I don't have proof of the cause (that would require a counterfactual birth), but he is disabled, has an abnormally oblong head, and this is the stated reason of the family (also not incontrovertible facts).

My understanding was that a large part of the reason was that unlike natural deliveries they can be scheduled and are thus far more convenient for the doctors.

I thought it was because of all the law suits brought about by the likes of former Sen. John Edwards.

There is not a reason for everything.

The spotted hyena is one of the most successful carnivores in Africa; yet females hyenas lack an external vaginal opening and therefore give birth through their narrow clitoris (...). During parturition, the clitoris ruptures in order to facilitate the passage of the young, and may take weeks to heal.


One can only imagine the extreme pain and difficulty involved in this; yet it's unlikely there's an evolutionary justification to be found. It's most probably an accident -- a quite unfortunate one for the female hyena.

One possible justification is that this genital configurations prevents forcible rape, as the wiki article points out. This allows females to have more control over the genetic traits of their offspring.

That’s probably just a side-effect of the greatly increased testosterone in female hyenas.

I don’t think anyone can really say whether the testosterone or matriarchal organization came first (or co-evolved).

the term "forcible rape" is rife with difficult implications.

"Many experts now believe that rape is best understood as an act of unwanted bodily invasion that need not involve force."


Since hyaenas are not going to promise to marry you or claim to be an Albanian prince to get sex forcible rape is pretty accurate.

I agree with you. Sorry if I wasn't clear, I just using the language in the wiki article. I guess the point is more that with a normal vaginal opening any male physically strong enough can impregnate a female. With the Hayena configuration my understanding is that the female has to consciously retract her clitoris to make impregnation possible at all.

So yes the male could still coerce, through emotional manipulation or threat of physical force, a female to comply without direct physical force but I don't know how applicable that is to hayenas (or most non-human animals).

FWIW, it's now recognized that the parts of the human female anatomy that are sensitive to arousal (parts that are essentially analogous to the shaft of the penis and to the skin of the testicles in their sensitivity and in their ability to convey pleasure) surround the entire vaginal opening and portions of the vaginal wall.

No, they're not as sensitive as the clitoris (and no, I don't think we know precisely how sensitive the hyena clitoris may or may not be) but human women also give birth through tissue that is dense with nerve endings and more sensitive to both pleasure and pain than, say, that on the outer surface of your arm.

In general, vestigial traits hang around because there is little selection pressure against them, but new traits don't usually seem to show up & take over for no good reason.

IIRC, this also means that the first litter systematically dies off.

I vaguely recall a guide explaining this during a SafariLive stream[1]

1. https://wildearth.tv/safarilive/

Dr. Karp, who is quoted at the beginning of the article, wrote an excellent book and released an excellent DVD. If you are a new parent, I highly, highly recommend you at least watch the DVD about the "5 S's" - it will make an incredibly positive difference in how well your first few months with a new baby will go.

Couldn't agree more. The book they cite (Happiest Baby on the Block) goes through the 5 S's and it's a life saver. His "4th Trimester" theory is just about the most sensible description of newborn behavior.

So true. The 5S's was like this magical switch that I could flip to chill out my screaming newborn. It was an incredible experience seeing how well it worked.

> Warrener and her colleagues found that wider hips do not increase the cost of locomotion. Indeed, both women and men are equally efficient at walking and running

> I have a number of papers that show that women are great walkers, and in some particular tasks women are better—they don’t use as much energy, they don’t build as much heat, they can carry heavier loads with less of an energetic burden.

I am not a biologist, but those parts just don't click for me; how/why would evolution have jump through all the costly hoops to differentiate the pelvis of males and females so significantly if the result was to give a locomotion system that was overall worse to the individuals who needed it the most for their survival, without any benefit in return ?

Why is sexual differentiation necessarily costly in every case? There are many sex differences that give an advantage for one gender that would have been an advantage, or no cost, for the other gender, but weren't as strongly required and so don't exist. Sexual differentiation may be less _likely_ for any given trait, but traits tend to pop up on random chromosomes, or the side effects of sex hormones be farther-reaching than necessary and evolution just "didn't bother to correct," and so I'd expect that some traits that don't necessarily need to be dimorphic (but are needed by one gender or the other) might become dimorphic just by chance.

Men have deeper voices than women. What would be the disadvantage for baritone women? You could argue that a deeper voice makes you less easily heard by prey... but then what's the advantage for women to have a higher pitched voice? Why didn't we all continue this trend to speak at the registry of blue whales? I suspect it's one of those things that "just sort of happened" and then it became a positive feedback loop spurred on by sexual attraction as a result of this initial differentiation, and now we're just at a pretty good state spurred on by a combination of random chance, survival advantage, and a little reproductive enforcement.

Increased sexual dimorphism (and a genetic/hormonal configuration that lowers the cost and increases the odds of sexual dimorphism happening for any given feature) is actually a positive thing for some animals depending on their social and reproductive strategies. When sexual dimorphism is high, you tend to see more random differences that pop up between the sexes but that may or may not provide any evolutionary advantage beyond "well, the other sex is just attracted to it now so let's keep this party going." When dimorphism is low, differences generally have to provide a stronger survival advantage.

Evolution isn't always straightforward or "carefully thought out." The hoops it jumps through aren't always costly and don't always have a rhyme or reason. It's often chaotic and and takes weird turns and it's not like humans are at a "final state" anyway. We're evolving.

I'm not _necessarily_ disagreeing with you (although it's probably ultimately easier to look at the physics, not biology, to prove or disprove your point) but I'm just saying that I think the situation is vastly more complicated than "sexual differences are costly." I don't think they're necessarily costly, simply less likely. A subtle, but important difference.

> but then what's the advantage for women to have a higher pitched voice?

Living in a neighborhood with a lot of teenagers, I will dare a guess; this loud, high pitched scream was probably a very efficient call for help.

But I see your point, and I agree that the answer could be just as simple as randomness of genetics. It just feels rather unsatisfactory for a change who must have taken far more than one single mutation to be that common. Feels like someone winning the lottery a dozen times in a row.

Known genes associated with hip bone size in women (but not men) are found on chromosome 2 (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2522269/). But the expression of those genes is likely controlled by estrogen (http://www.sciencemag.org/news/2016/04/woman-s-pelvis-narrow...)

Individuals who have androgen insensitivity syndrome (XY chromosomes, but that don't respond to testosterone and are, for most intents and purposes, sterile females) will have large hips/pelvic bones.

So, yes, hip size takes a few modified base pairs (although probably all within one gene, or pretty close together on the same chromosome), but evolution only needs to "decide" (heavy emphasis on the quotes there) that this physiological change is hormonally triggered. Many skeletal changes are hormonally triggered, so this may have even been the easiest/most likely path.

Mothers preserving energy and being able to carry more directly benefit the survival of offspring (since that's who they're carrying and where their surplus energy is going), whereas an improvement in those areas for fathers doesn't have as direct of an impact so it doesn't get selected for.

>without any benefit in return ?

Isn't the implied benefit that it might allow for an easier birth?

"in some particular tasks women are better"

I assume men's hips are still better for tasks traditionally associated with the male gender role - e.g. being hunters and warriors.

> ...and in hunter-gatherer societies, women walk, on average, 5.5 miles per day, often while carrying and feeding infants as well.

Quoting a one-sided statistic like this is something the editor should have caught. The 5.5 miles figure doesn’t support anything if the figure for men is ten; it’s great support if that figure is four; but without either figure what does it mean?

None of my three children were born in the supine position and the eldest is now almost thirty so I am a little surprised to read that it is still common. And while my wife found it painful to some extent it is quite clear that she also enjoyed the process to a fairly large degree. But this was in a maternity unit that had essentially no rules beyond do what makes mother and baby happy, and have the capability to deal with a crisis if it should occur. My wife felt free to arrange herself in whatever position was most effective and to make as much noise as she liked when it got tough.

I think that many women end up going into labour in a fearful frame of mind because of the constant reminders that it will be painful and this coupled with midwives intent on following timetables and doing things their way results in a stressful time for all.

As everyone else mentions, I am aware that my sample is not large and that there are many who have had a different experience.

This article was originally published in Undark Magazine:


Not only how difficult labor is, but how helpless a child is for so long. Years before they can walk, for example. Compare that to a fawn, which stands up and follows its mom after just a few minutes into the world.

If we carried our children until they were sufficiently physically developed to stand, they'd kill the mothers in childbirth 19 times out of 20.

As our brains became more advanced, our crania became larger and more dangerous to birth at full term. But as our intelligence increased, so did our ability to care for infants that were essentially born premature.

So now even our full term babies are born so early that they need another 3 months (sometimes referred to as the "fourth trimester") just to be mature enough to sleep properly, among other things. But as intelligent humans, we're able to care for them and devise ways to carry them with us and protect and nurture them despite their extreme helplessness.

FWIW, the offspring of carnivorous mammals, though not born quite as "premature" as humans, are often as underdeveloped at birth as a 3-month-old baby. I mean, have you ever seen a newborn kitten or puppy? Eyes closed, barely able to crawl to its mother's teats?

The need for a prey animal - especially one that depends on speed for self-preservation - to be able to escape from within minutes of its birth is very different from the survival requirements for a carnivore or even a prey animal that gives birth in a hidden den (like many rodents).

Babies start crawling at about 6 months, and walking somewhere between 9 months and a year. I have a two year old, and she is far from helpless.

That’s just a personal anecdote. Some babies never crawl at all and some toddlers don’t start walking until much later than 12 months. And your 2yo toddler is still nothing compared to the mobility and world-awareness of a two-month-old fawn, which has already learned to recognize and outrun predators at this age.

The fact that there’s such a spread for these otherwise extremely important life stages in humans shows a lack of maturity in their development compared to other mammals, not the inverse. Something is a little different about us.

If we were to compares ourselves to actual animals. Personal anecdotes wouldn't matter as fatality rates would increase without modern comforts not afford to animals. The child doesn't crawl or start walking for another year, child would die as the parents wouldn't care for weak off-spring.

It sounds harsh when discussing humans but the differences in development occur because our death rate is low compared to wild animals. Thus allowing weak genes to be passed e.g., not being able to crawl or walk for 3 years double or triple the normal would not be tolerated in the animal kingdom.

Not necessarily. It depends on why the offspring couldn't crawl or walk for longer. If it's associated with something that increases survival in mature members of the species, it might be tolerated, even selected for.

For example, if the child is delayed in walking because more metabolic resources are being channeled to larger brain development, that could be a survival benefit. I use that example, because that's essentially the theory of what happened in humans, in comparison to chimpanzees. (Obviously not 1 child randomly taking 2x or 3x to develop, but a slow evolutionary process.)

Chimps are relatively helpless when they are born too, relative to most species. They nurse for years, stay with parents for years, are totally reliant on them for survival, etc. But they are not so helpless as humans. It's estimated human gestation would have to be about 18 months for newborns to be at a comparable stage of cognitive development as newborn chimps.

So, from this perspective, we do take 2x the time in comparison to chimps, and yet it was tolerated. I guess my overall point is that evolution is more complicated than how quickly an offspring can crawl or walk or be independent.

Follow the money?

On one side, I believe Doctors get paid more by performing a C-section. [1]

On the other, it may involve less risk, which reduces the likelihood of malpractice lawsuits? [2]

1 - https://scholar.princeton.edu/sites/default/files/dalexand/f...

2 - https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3096673/

This is true, at least in my country there is a high amount of C-sections and studies show that most of them are done for the money.

Interesting article. But it doesnt really explain some key questions.i have always wondered why are humans so ineffective at giving births. Cangaroo, for example, gives birth to their baby at a much earlier stage, when it's only 1 inch big and then keeps it in the pouch. No pain, no extreme labor.

I've read a couple articles that touch on this. The current theory has been summarized as there being an evolutionary arms race between genes that benefit the child at the mother's expense and genes that preserve the mother while being somewhat detrimental to the child's fitness (but as a result beneficial to her other offspring).

In this regard, longer gestation and a larger cranium are both better for the child. But our large crania are difficult to fit through the various choke points in the birth canal, and endanger the mother's life. The result is basically gestation as long as possible and crania as large as possible to permit natural childbirth to usually be non-fatal -- but that inflection point is one where even a non-fatal childbirth is difficult and painful.

(There are also elements of the theory that relate to frequency of fertility, and why human menstrual bleeding far exceeds that of other mammals.)

Because of the external gestation, my understanding is that survival rates for marsupial offspring are lower than for mammals. As for other mammals, giving birth is difficult for them too, though we don't have a way to measure how their pain compares to ours. However, no other mammal has gone down an evolutionary pathway where its fitness depends on brain size, so no other mammal has to contend with evolutionary pressures that so directly affect the ease of birth. (Plus, bipedal mammals with upright gaits are rare, so the evolutionary pressure affecting pelvic shape are different.)

To be fair to humans, we are born at a pretty early stage also. Human babies are all but helpless at 12 months after birth and pretty helpless for another 12 months after that (and then they are still rather helpless).

A kangaroo leaves the pouch in around 8 months.

Kangaroos are marsupials, which are non-eutherian. Humans (and, indeed, most mammals we're familiar with) are eutherians. The birthing process is quite different, and so makes for a poor comparison (for one, humans don't have a pouch). A better question would be to compare human pain to other, eutherian animals who do not experience much pain in delivery (see: any nature documentary).

Humans have large heads and walk upright. These are great for many things, but not giving birth.

Ineffective because natural selection doesn’t over optimize.

EEG suggests earlier born babies can have huge merits in intelligence evolution: https://www.scientificamerican.com/article/does-a-newborn-s-...

Well, you’re not alone in wondering that. In fact it was noted in the Bible as part of God’s curse when we became “enlightened” by eating fruit from the tree of knowledge. We’ve at least known it’s harder than it should be for a very long time.

We are very effective at breeding, especially with the help of science and technology. The inefficiency of birth, if true, hardly matters.

>We are very effective at breeding, especially with the help of science and technology.

In what sense? Our production rate is substantially lower than most other animals; mothers-to-be are made weaker than other animals during the process; the threat of death in childbirth for both child/mother is hardly the lowest of other animals

We have a relatively high population now, but its hard to imagine that its due to an efficient breeding process; rather our survival rate post-birth, lifespan and our phenomenal ability to edit the environment to increase resource production to support higher populations are likely better explanations

Put a pair of rabbits in a room and a pair of humans, with all needs met. We're not even competitive

Do you mean kangaroos?

Maybe that's how they spell kangaroo somewhere. Like color and colour.

Who said it is? Billions manage to do it just fine, with 1/100 the preparation.

Firstly the people saying that birth is hard in this article are scienstists who study birth in humans. Human births are much longer, more complex, and more painful than most other mammals and this article goes into some arguments as to why that is.

I don't who these billions are that you're talking about, but historically giving birth has been a very deadly affair for women.

I dug up some numbers which support what you're saying:

https://www.indexmundi.com/g/r.aspx?v=2223 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1633559/figure/... https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1633559/

It looks like about 1% of pregnancies ended in death historically, and that matches what's happening in the places with the worst healthcare today.

With good healthcare, the risk nearly vanishes.

Spoken like someone who has never done it and never will, with only the confidence that comes from total ignorance.

Prior to modern medicine, childbirth killed perhaps a billion women. Even today, it's still a major cause of death for women of childbearing age. I sure wouldn't call it "just fine."

> Who said it is?

The article. Which quotes several expert anthropologists.

Your comment contributes nothing to the discussion and suggests that you haven't read the article.

No mentions of Genesis 3:16b yet: I will make your pains in childbearing very severe; with painful labor you will give birth to children.

Oh you guys should read "The Good Book of Human Nature: An Evolutionary Reading of the Bible" It explains a lot of the stories inside the Bible on a evolutionary way. https://www.amazon.com/Good-Book-Human-Nature-Evolutionary/d...

Talk about a shitty god.

"Birth is hard because we ate of the tree of knowledge" seems like a metaphor for "birth is hard because we evolved big heads".

If anyone finds this sort of thing interesting you might enjoy Jordan Peterson's lectures on the Old Testament. (podcast or youtube)

Also Quran 46:15: "And We have enjoined upon man, to his parents, good treatment. His mother carried him with hardship and gave birth to him with hardship, and his gestation and weaning [period] is thirty months. [He grows] until, when he reaches maturity and reaches [the age of] forty years, he says, "My Lord, enable me to be grateful for Your favor which You have bestowed upon me and upon my parents and to work righteousness of which You will approve and make righteous for me my offspring. Indeed, I have repented to You, and indeed, I am of the Muslims.""

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