Has maternal mortality due to child birth dropped in England over the past 100 years?
The 2006 paper, British maternal mortality in the 19th and early 20th centuries examines this.
Figure 1 illustrates the incredible improvement, just up to 1970 alone.
Annual death rate per 1000 total births from maternal mortality in England and Wales (1850-1970)
We can see from the chart that, around 100 years ago, the death rate was 40 per 1000, or a 4% chance. That is, one in 25 women giving birth would die.
Does maternal mortality have a significant effect on life expectancy of women?
The 2008 paper Life Expectancy and Human Capital Investments: Evidence From Maternal Mortality Declines looked at Sri Lanka (admittedly not England), and the improvement in maternal mortality just between 1946 and 1953. They concluded it
increased female life expectancy at age 15 by 4.1%
That is a very impressive improvement. By aged 15, girls have already passed the dangerous first years of their lives. To improve their expected lifespan by an additional 4%, from only the reduced risk of dying during child-birth gained in seven years in the mid-1900s, is almost staggering.
Are women more likely to die during later pregnancies than earlier ones?
It's not quite that simple.
The first birth is the most dangerous, and then the next few are safer. As the woman has more children, the risk grows again.
I draw this conclusion from the review paper The Relationship Between Fertility and Maternal Mortality from the book Contraceptive Use and Controlled Fertility: Health Issues for Women and Children Background Papers.
All the population-based studies indicate and results from hospital studies generally confirm that the first birth and births of high order are strong risk factors for maternal mortality (Table 2). These studies indicate a J-or U-shaped risk with parity: high during the first pregnancy, lowest during the second or third, and high again by the fifth pregnancy. A similar pattern is found for gravidity, with an even stronger relative risk for first pregnancies relative to later-order pregnancies than is observed for first births.