This blog is intended to go along with Population: An Introduction to Concepts and Issues, by John R. Weeks, published by Cengage Learning. The latest edition is the 13th (it will be out in January 2020), but this blog is meant to complement any edition of the book by showing the way in which demographic issues are regularly in the news.

You can download an iPhone app for the 13th edition from the App Store (search for Weeks Population).

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Monday, December 3, 2012

A Piece in the Low Birthweight Puzzle

Low birthweight (LBW) is an important cause of early infant mortality (neonatality). One underlying contributor to LBW is prematurity, as I have noted before, but researchers looking at data for sub-Saharan Africa have found that a mother being infected with malaria during pregnancy is also an important cause of LBW. Thomas P. Eisele and his colleagues at Tulane University used Demographic and Health Survey (DHS) data from 32 sub-Saharan African countries to show that women who are treated for malaria during pregnancy (with ITPp), and who use insecticide-treated mosquito nets (ITNs) are less likely to have a low birthweight baby and are thus less likely to experience the early death of the child. Here's the bottom from their analysis, just published in The Lancet Infectious Diseases:
We analysed 32 national cross-sectional datasets. Exposure of women in their first or second pregnancy to full malaria prevention with IPTp or ITNs was significantly associated with decreased risk of neonatal mortality (protective efficacy [PE] 18%, 95% CI 4–30; incidence rate ratio [IRR] 0•820, 95% CI 0•698–0•962), compared with newborn babies of mothers with no protection, after exact matching and controlling for potential confounding factors. Compared with women with no protection, exposure of pregnant women during their first two pregnancies to full malaria prevention in pregnancy through IPTp or ITNs was significantly associated with reduced odds of low birthweight (PE 21%, 14–27; IRR 0•792, 0•732–0•857), as measured by a combination of weight and birth size perceived by the mother, after exact matching and controlling for potential confounding factors.
The sad part of the story is that, as the authors note in their conclusion, "ITN use in pregnant women and coverage of IPTp of at least two doses of sulfadoxine–pyrimethamine are lagging in Africa, especially in countries with the highest malaria transmission." So, the women who need the treatment the most are among the least likely to be getting it.


  1. Hello Dr Weeks,

    I have enjoyed reading your blog a great deal over the last year or so. I am wondering if I could present you with a question/challenge. Can you provide for your readers a handful of countries with positive and hopeful demographic profiles? I mean, I look at material from Japan and Spain and it seems, well, not good. I then look at Uganda and Nigeria and find a high TFR but economically and politically I don't see how this can be handled productively and positively without internal strife and, possibly, civil war or genocide.

    So what country is doing well? The USA? Mexico? Armenia perhaps? Kazakhstan? I'm sure you are busy but it seems like an interesting question. Perhaps if you do not have time to write something on it yourself you could just post a link to a couple of success stories out there.


    1. This is a very interesting question. To a certain extent, "doing well" is in the eyes of the beholder, and it also tends to be a bit ephemeral. Demographic success today (e.g, China's age structure) doesn't guarantee long-term success. But I will have to think about this some more.