China may be storing up future social problems with its “one child rule,” given that its ratio of boy to girl babies is high, even when compared with an entire Chinese population living in Europe, according to one recent estimate.

The estimators concluded that this constraint was associated with antenatal screening and selective abortion of female fetuses—officially outlawed—and low registration of female babies. The ratio of boy to girl babies among live births was significantly higher for Chinese babies in China in 2000 than for those born in the Chinese population of almost 17 500 in Tuscany, Italy, and for non-Chinese babies there (1.168 versus 0.969 and 1.058, respectively). The overall sex ratio of live births was similar for Chinese and non-Chinese babies in Tuscany during 1992–02.

Antenatal sexing is available to the Chinese in Tuscany, and antenatal care and abortion are free. There was no evidence that these Chinese parents had lost their cultural preference for boys, but rather they did not need to resort to drastic measures to ensure they had sons, as no evidence was found of other influences to account for the low sex ratio.

The data on newborn babies in Tuscany were available from the Tuscan neonatal screening programme for cystic fibrosis and, in China, from the National Bureau of Statistics and United States Census Bureau.

The high sex ratio of babies in China is well known, but previous studies have not compared it with a Chinese population living elsewhere.