Exceptionally high sex ratios at birth among Mainland Chinese giving birth in Hong Kong SAR

China has one of the most skewed sex ratio at birth (SRB) in the world. However, while the SRB in Hong Kong (HK) has historically been much lower (~106), it has recently seen a dramatic increase.

We use a very large, detailed data-set (N 850,331) of all recorded births in HK between 1995 and 2009 to calculate new SRBs for the territory both by parity and, by virtue of the large sample size, by a much more detailed set of immigrant partnership variables.

At parity one, the SRBs of both HK born couples and other immigrants are broadly similar. At parity two, the SRB of HK born parents is 107.8. Among recent arrived immigrants from Mainland China, this rises to 127.1. At parities three and four, the HK born SRBs rise to 110.6 and 116.6, while the recently arrived Mainland Chinese SRB is 216.0 and 264.3.

HK has been serving as an outlet for 'elite Mainland couples' able to afford the costs of giving birth there to circumvent the both anti-prenatal sex selection legislation and family planning regulations to achieve the desired effect: a male offspring.