Hey!  So a few weeks ago Bill and Melinda Gates reached out to us about making a collaborative video based on a theme in their annual letter.  This is something that they write every year to share their philanthropic goals for the coming months.  One of their priorities for 2017 has to do with maternal and infant health.  They wanna support initiatives that ensure women remain healthy through pregnancy and birth and in the first years of their child's life.  We put it in the description so you can go check it out for yourself.  The Gates have done a lot of great work to help elevate important topics around global health an education, and I'm really excited to be working with them on this project.  So, check it out.

So you might remember Dr. Robert Martin, who you
re familiar with from episodes like "Breast Episode Ever" and "Why did King Tut Have a Flat Head?"  He's a biological anthropologist and has spent his career researching various aspects of hominid evolution.  A big part of his work focuses on the physical aspects of human reproduction and childbirth, and how trends and practices in childbirth have changed throughout time.  It got me thinking of that face that I made in the King Tut video;  before then I'd never truly realized the logistical constraints of human childbirth.  I mea, you've gotta navigate this grapefruit sized head and shoulders through an opening of roughly the same size and make a turn to get around the tailbone in the process.  When you compare the pelvic size and shape to that of our closest great ape relatives, ours is disproportionately smaller and more obtuse, and that's because the act of walking permanently upright, known as bipedal locomotion, actually changed the shape of that pelvic opening.  This, in addition to human babies having a longer gestation time, overall larger body size, and massive heads, leads to a lot of complications when it comes to human birthing practices.  In fact, in a recent blog post, Dr. Martin wrote, "...asute analyses of brain size and pelvic anatomy in our fossil predecessors... have confirmed... that births first began to become challenging when the genus Homo emerged around two million years ago."  This means that women may have been relying on personal assistance in order to give birth for as long as two million years.  So I started to wonder, how has our inability to give birth easily impacted birth rates for both mother and child?  Save the Children estimates that one million babies die the day they're born every year.  So, why does this happen and re things getting any better?  Spoiler alert; these things are actually improving and I went to talk to Dr. Martin to get some answers.

Dr. Robert Martin: This is what a baby's head looks like at birth, and that head has to fit through the pelvis.  So the baby goes in with his head facing sideways, and then when he's halfway through the pelvis it turns ninety degrees to point backwards.  It all boils down to a difficult passage through the pelvis because of this trade off between adaptation of the pelvis for upright walking and this big brain.  So all of that points to the need for some kind of assistance.  We don't know exactly when, but we can trace this process through the fossil record fairly effectively, and my guess is that we started needing midwives about a million years ago, or some kind of help.

Emily:  Woe.  You mentioned earlier that we have a great record of knowing how humans have  evolved over time and how the evolution of birthing practices have evolved over time, so you, can you talk a little bit about some of the examples that we have, uh, in the fossil record?

R: So this here, this is one side of the pelvis of Lucy, the famous Australopothecus from Ethiopia.  So if you mirror image the pelvis and put it together, you can work out how big the birth canal was, and we can calculate how big the baby's head was likely to be, but then when you get up to Homoerectus, by 1.5 million years ago with early Homo, uh, we almost certainly had the beginnings of a difficult birth.  They would have slower births and maybe they already needed midwives at that stage, it's quite possible.
I think midwives have been undervalued.  I mean, there's been a medicalization of birth, and a drive toward having births in hospitals;  it's much better for women, psychologically at least, to be working with a midwife than to go into the impersonal environment of a maternity.  There was a study in Holland which showed that if you have a midwife in hospital, compared to an obstetrician in that same hospital, birth took twice as long with the obstetrician than with the midwives.  I mean, it's pretty dramatic evidence to me.

E: Something like 300,000 women die because of pregnancy related issues, but most of those are preventable.  I mean, sometimes you get blockages of the birth canal, but a lot of that just has to do with access to basic healthcare and, uh, assistance in the process.  It seems pretty logical to think that if you provide more access to healthcare and to nutrition to decrease the  number of children who are dying of malnutrition, then that would be beneficial all around.

R: This is absolutely true, I mean medical science has made huge leaps forward, but in industrialized countries we've managed to get birth related mortality down so that we're talking about a few per hundred thousand, so I mean these are really pretty low levels.  But here's the thing, if you just take industrialized countries where because of hospital services we've managed to reduce mortality, the lowest country on the list for industrialized countries in the United States.  How come the richest countries in the world has one of the highest levels of mortality around?
There was one drastic case which was the state of Texas.  In the state of Texas, the maternal mortality was actually not rising very much until 2011, and then it doubled.  It just shot up, and it's stayed at that level ever since.  There's no health related factor that can explain that, and the only explanation I've seen is in 2011, a lot of prenatal clinics were closed.  And so I think there is a good possibility that a political decision in the state of Texas has actually doubled the rate of mortality in that state.

E: Wow.  So that's kind of a shocking example of how decreasing the access to healthcare facilities actually increases the rate on infant and mother mortality.  Despite those kind of statistics, uh, things are improving globally for women and for infant care, especially if you're looking in the scale of the last hundred years or so.  The percentage of children that are dying between age zero and five has decreased forty percent in the last hundred years.  From instances, things might look like they're getting worse, but overall things are improving.

R: Oh, absolutely, and I don't want to over-exaggerate things, I mean, the United States is last on the list for industrialized countries, but it's still pretty low.  Medical intervention and monitoring has got the death rate down considerably.  It's quite a bit worse in developing countries, and the highest rates are in Africa.  Africa has real problems with health provision I think, and so we can see there the problems you get if you don't have regular monitoring.

E: We have the benefit of technology and medical resources that hypothetically could be available to everybody alive today.  122 million children have been able to live because of access to healthcare and education.  So that, to me, seems like huge progress.  What to do imagine for the future of humanity if everybody could have access to healthcare, you know, provided you have some idea of what our evolutionary trajection might be?

R: Yes, the first thing I would say is that a key to that improvement you've mentioned is prenatal car.  That has already reduced the prob;ems enormously and improves the prospects of births.  Unfortunately, a lot of people think the easy way out is to have Cesarean births because then you don't have any problem with passing through the pelvis at all.  That has got out of hand because WHO reckons that for medical reasons you might need to have a Cesarean every one in ten of one in seven births, something like that.  In the United States right now, one in three births is by Cesarean, so uh, it's more than tripled in the, over the course of forty years or so.  You have full anesthesia for a Cesarean, it's a major operation; it has all kind of side effects.  But the example I have given in my writings is that in bulldogs, dogs with really wide heads, we're talking about 85 to 95 percent Cesareans, and if we don't watch it, we're going to end up like bulldogs.

E: Wow.  Man, I'm just, I'm grateful for mothers everywhere.