Isn't it curious that a species would spend much energy constructing a dumb-luck lottery to filter its genes through?
All reproduction and 'fitness' issues are apparently dumb-luck from the perspective of any given individual at any point on the path. If you look at all those cute little turtles skittering to the sea, you know perfectly well that barely 1% of them will survive to get back and lay their own eggs. From natural systems point of view, all the 'failures' are a good source of protein for a wide variety of predators. And for all deaths, whether reptile, mammal or fungi, the constituent parts of the organism are useful to any number of other organisms.
For humans, I don't see the 'surprising' question. Lots of women and even more children die or are permanently injured during childbirth in current and historical circumstances lacking modern medical support or sophisticated midwifery. (And no comments about the age-old wisdom of communities. It's another matter of mere dumb-luck if you happen to be born in a place where community 'wisdom' does some real rather than imagined good.) Given the complexity and interdependence of our physical and mental functioning, I don't see any other way.
It's a constant process of cooperative, reinforcing processes with tradeoffs and limitations, all of which come together for a good or bad, wonderful or dreadful outcome. And remember, it's not just the birth the mother and child have to survive unharmed. They also have to get through the next year or so with a diet for the mother adequate to feed the child and maintain her own health. More cooperation, more tradeoffs. And they both have to survive any contagious disease that races through their community.
I think modern people, insulated from the vagaries of good & poor seasons on the land, and well-sheltered and clothed as well as medically shielded by vaccination from the ravages of measles or whooping cough, simply forget just how fragile human life really is.
When you look at life expectancy tables from history, they do
not mean that people lived short, miserable lives and died before they were 40. What they mean is that many, many people, lots and lots of people, didn't live until their first, fifth or 15th birthdays. It was quite possible, not uncommon but always sad, for women to bear 8 or more children and never see even the possibility of a grandchild because none of them lived to adulthood. Those vast numbers of people with very, very short lifespans distort the average downwards.
Just remember one simple length-of-life fact. The longer you live, the longer you're likely to live.
Our young are just as vulnerable, if not more so, as the young of any other mammal. And human women are definitely in more danger during childbirth than any other mammal. It's only protection from food scarcity and contagious disease as well as good shelter and clothing that allows us to see almost 100% of our children survive to adulthood. We think of children's funerals as rare and 'wrong'. "A parent shouldn't have to bury a child." Until very few generations ago, children's funerals were frequent, and during epidemics they were the majority of deaths.