But what if child mortality is up mainly because of high birth rates? When their religion/culture calls for having as many kids as possible, it causes problems that lead to high child mortality. It's very difficult to change religion/culture.
http://www.ted.com/talks/lang/en/hans_rosling_religions_and_...
Personally I'd guess the birth rate there is a direct result of the church's push for more children, but I don't really know.