Question

7th grade history - How does the growth of the world's population today compare with its growth 100 years ago? Explain why the changes have taken place.
Ms. Sue
https://ourworldindata.org/world-population-growth/

https://en.wikipedia.org/wiki/World_population

Why? Fantastic medical advances.

Reed
Actually, it's pretty complicated and has to do with medical advances that help people live longer compared to lower birth rates. This is a paper that may be "over your head", but the introduction/summary may help you.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2781829/
bobpursley
https://ourworldindata.org/wp-content/uploads/2013/05/updated-World-Population-Growth-1750-2100-768x538.png
note on this graph, in 1959 oral birth control pills were invented, and by 1960 were widely available.
Ms. Sue
That's why my last child was born in 1958. <g>
Reed
Yes, birth control has much to do with it. Families are smaller now than they were 100 years ago, or even in the 1950s. Women work outside the home more now than in the past, so want smaller families to take care of. And if family size can be controlled instead of just happening, a family's economic well-being is a factor. Children are expensive to raise, and some couples don't want four or more children to raise, but are happy with one or two.