Saturday, October 15, 2005

Biased reporting - please take off your blinkers !

" In Asia, at least 60 million girls are "missing", according to the State of World Population 2005 report." What's the explanation ? The media have once again trotted out the old - " Strong preference for boys in some countries has led to the elimination of millions of girls through prenatal sex selection". Unfortunately, no one has ever bothered to even consider that it would be nearly physically impossible to terminate so many fetuses ! This explanation is off by at least one order of magnitude ! While it is possible that the sex ratio is changing because of female feticide, this needs to be proven with raw hard data.

If this hypothesis ( that the decline in females born is due to female feticide) is true, then the only explanation for the missing girls is that they have all been aborted. Now, the only inexpensive commonly available method of fetal gender determination uses ultrasound. Since this can be used to determine gender accurately only after 14 weeks ( since the fetal external genitals are visible only after 12 weeks) , this means that if selective female feticide needs to be performed, the doctor would need to do a second trimester abortion. This is a fairly complex medical procedure, which is usually performed only by gynecologists.

The 2001 Census figures for Punjab show that there are 1.7 million boys between the age of 0-6 years. If the sex ratio were normal (0.95) , we would expect to have 1.6 million girls. Since the census shows there are only 1.35 million girls, that means 250000 girls are “ missing “. If the newborn girls are missing because of abortions done after fetal sex determination as claimed, this means that 250000 mid-trimester abortions would have had to be carried out in Punjab in the past 5 years – a virtual epidemic of abortions , because this would mean 50000 mid-trimester abortions a year ! Mid-trimester abortions are like mini-deliveries, and are fairly complicated to carry out. They can be done safely only by a skilled gynecologist. It would be a simple matter to verify the number of abortions carried out in Punjab because most abortions are carried out in Govt recognized centers.( Since abortions are legal, there is no need for doctors to perform these on the sly , so one would expect all the abortions performed to be documented, even though the reason given for terminating the pregnancy may be false.) If the study shows that the number of abortions is not so high, this means that the hypothesis is not true, no matter how appealing and logical it may be. We then need to search for an alternative explanation for the declining sex ratio, rather than blame illegal sex determination procedures for this ! Such a study is important because it is the only way of proving the proposition that female feticide is altering the sex ratio, and will lend valuable support to the demand that the laws which ban female feticide be more strictly implemented.

Should we be looking for alternative explantations ? Yes, we do need to keep an open mind !

Here's an interesting alternative hypothesis which the Indian mainstream media refuses to publish ! I wonder why ?

" The Case Of Asia's "Missing Women" - The culprit may not be government policy, but hepatitis B virus
http://www.businessweek.com/magazine/content/05_09/b3922034_mz007.htm

In 1990 my Harvard colleague Amartya Sen caused a stir by observing in The New York Review of Books that excess female mortality in China, India, and other Asian countries meant that there were 100 million women fewer in the world than there should be. The presumption was that the excess mortality came from discrimination against women by men and governments. Although the estimate was lowered to 60 million by demographer Ansley Coale's more detailed analysis in the 1991 Population & Development Review, this still shockingly large number became a symbol of discrimination against women in developing countries. Many people think the reason is abortion and the killing of newborn girls. But new research suggests another reason. Harvard economist Emily Oster, in her PhD thesis "Hepatitis B and the Case of the Missing Women," suggests that biology explains a good deal of the missing-women puzzle.

In Western countries, such as the U.S., the ratio of male to female births is around 1.05. Higher male mortality leads to decreasing male-female sex ratios as the population segment gets older. In the whole population, the two forces roughly cancel each other out, leading to an overall male-female ratio close to 1. In contrast, since at least 1980, male-female ratios are around 1.08 in China, India, and Pakistan. This demographic phenomenon is limited to Asia and does not relate to economic development. The male-female ratios are not high in sub-Saharan Africa and Latin America.

The Sen-Coale assumption was that the high ratios in Asia reflected high female mortality rates. They calculated how many women would have existed if female mortality rates had been normal, which Coale computed in relation to a country's overall life expectancy. The difference between this hypothetical number of women and the actual number equaled the missing women.

Oster argues that this calculation overlooked something crucial -- unusually high male-female birth ratios in Asia years before abortion became widespread. Given mortality rates by gender, a rise in the male-female birth ratio leads to an increase in the male-female population ratio. Motivated by Baruch Blumberg's book, Hepatitis B: The Hunt for a Killer Virus, Oster sees the high incidence of the hepatitis B virus (HBV) as a major culprit.

There is much evidence that parents infected by HBV are more likely to have male children. Places with substantial HBV -- Asia, Alaska, and parts of the the former Soviet Union -- tend to have high male-female birth ratios. Studies in Greece and France show that HBV-positive parents had male-female ratios for offsprings of 1.7 to 1.8, vs. 1.1 to 1.2 for those who are HBV-negative. This pattern also shows up among immigrants, with those from high HBV areas, such as China, having high male-female offspring ratios in the U.S.

The biological explanation for the HBV effect is unclear, though it may involve more frequent spontaneous abortion of female fetuses. But the effect is large, concentrated in certain regions, and susceptible to elimination via the HBV vaccine. In Alaska, the use of the HBV vaccine in 1982 led to a sharp decline in high male-female birth ratios.

Among Asian countries, the HBV influence is greatest in China, explaining 75% of Coale's missing women. In India, the adjustment is less important, explaining only 17%. For Asian countries in general, Oster locates 46% of the absent women, ending up with 33 million missing, rather than Coale's 60 million or Sen's 107 million.

Looking ahead, broader use of the HBV vaccine should lower male-female ratios. But another force -- sex-selective abortion -- which wasn't critical before the 1980s, is growing in importance because of the spread of ultrasound technology and, in China, the one-child policy. In Chinese censuses, the male-female birth ratio rose from 1.09 in '82 to 1.13 in '89 and 1.18 in 2000. The 1982 ratio likely reflected HBV prevalence but the subsequent increases probably reflected sex-selection. An obvious countermeasure: Eliminate the one-child policy.

The Oster research features interactions between biology and family behavior and government policy in the sensitive area of gender studies. This is the kind of research that Harvard President Larry Summers recently advocated in widely criticized remarks. Fortunately, the typical approach in economics is to take on almost any topic that can be usefully tackled with economic tools and let the data speak for themselves.


Robert J. Barro is a professor of economics at Harvard University and a senior fellow of the Hoover Institution ([email protected]). "

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