The Case of Asia’s ‘Missing Women’

06/17/05

I just read the article from the Business Week by Robert J. Barro, a professor of economics at Harvard University, about the case of Asia’s Missing Women.

In Western countries, such as the United States, the ratio of male to female births is around 1.05 and a higher male mortality leads to the decreasing of male-female sex ratio as the population segment gets older. In the big picture, the two forces cancel each other out, leading to an overall male-female ratio close to 1.

But Asian countries, as we have known, their culture is the big factor that makes the male-female ratio in Asian countries higher than the Western countries. For example, China has a one-child policy and men are regarded as someone who carries the family name; therefore, in the past (or even nowadays), most of families chose to abandon their daughters or in the extreme case they killed the new born baby in order to preserve their right to have one child for a son. However, with new technology like ultrasound, family will be able to decide if they want to have that child since they are still in the womb. This leads to the higher ratio between male and female in Asian countries.

However, new research by the Harvard economist Emily Oster, in her PhD thesis “Hepatitis B and the Case of the Missing Women,” suggests that biology also explains the reason of missing women question.

There is plenty of evidence that parents infected by HBV are more likely to have male children. Places with substantial HBV- Asia, Alaska, and parts of the former Soviet Union- tend to have high male-female birth ratios. Studies in Greece and France show that the HBV-positive parents had male-female ratios for children of 1.7 to 1 comparing to those who are HBV-negative. This pattern is also true among immigrants, who came from the high HBV areas, such as China, have a higher male-female offspring ratios in the U.S.

In Alaska, the use of the HBV vaccine in 1982 led to a sharp decline in high male-female birth ratios.

The missing women in Asian countries stems from not only the culture and government policy but also the biology that also have a big influence to the male-female ratio.

It is very interesting research.

Tae Athikomvittaya