(VEGF) is released from platelets during bloodclotting: implications for measurement ofcirculating VEGF levels in clinical disease.Clin Sci (Lond) 1998;94:395–404.

3. Hormbrey E, Gillespie P, Turner K, Han C,Roberts A, McGrouther D, Harris AL. A crit-ical review of vascular endothelial growth fac-tor (VEGF) analysis in peripheral blood: is thecurrent literature meaningful? Clin Exp Metas-tasis 2002;19:651–663.

4. Wynendaele W, Derua R, Hoylaerts MF, Paw-inski A, Waelkens E, de Bruijn EA, ParidaensR, Merlevede W, van Oosterom AT. Vascularendothelial growth factor measured in plateletpoor plasma allows optimal separation be-tween cancer patients and volunteers: a key tostudy an angiogenic marker in vivo? Ann On-col 1999;10:965–971.

doi:10.1016/j.amjcard.2006.02.028

Where Have All the Baby Girls inChina Gone?

Two recent provocative articles1,2 con-cluded that prenatal sex determinationand female feticide have contributed tothe paucity of girls in India. Then the 2articles also made reference to a similartrend of missing baby girls in China andhinted at the same explanation.

China’s 1-child policy, which is arisk factor for increased coronary arterydisease in modern China,3 necessitatesthat the only child be a boy. This feudalidea of the son being able to carry onthe family name in contrast to a daugh-ter who once married carries her hus-bands name,4 in addition to the fact thatin rural areas a boy contributes “twoextra hands and one extra hand” tofarming, is still prevalent in China.

As we know, all around the world,male births outnumber female births;the normal ratio is constant at 105 or106 boys to 100 girls. This was the casein China in 1953, 1964, and 1982, butthe boy/girl ratio in China jumped to111.3 in 1990 and 118 in 2005 (Figure1). As a consequence, all the rumorsbegan to spread around the world—areall the girls in China either aborted ordrowned in a bucket of hot water afterbirth by the midwives?

However, there are other more logi-cal explanations than infanticide. Ac-cording to the Chinese census data in1990,5 the highly abnormal ratio of111.3 baby boys to 100 baby girls atbirth dropped to a ratio of 108 boys to

100 girls at toddler age and declinedfurther to a ratio of 107 boys to 100girls at elementary school age, whichapproaches the ratio in the rest of theworld (Figure 2). Now, certainly if thebaby girls had been killed at birth, theycould not have been resurrected.

Therefore, the only explanation thatmakes any sense is that the missing girlswere merely kept away from the censusseekers after they were born—the fam-ily either hid them in the back room orsent them to their relatives in remoteareas of China and when time came forthe girls to go to school they turned upagain. This, to me, is the only logicalexplanation for a higher than normalboy/girl ratio at birth in modern China.

Of course, if China’s 1-child policyis strictly enforced and if every neonateis to be a male child, there will not beany more female babies born to grow up

and reproduce. I do not think this is agood method of “natural” populationcontrol China intends to follow.5

Tsung O. Cheng, MD

Department of MedicineGeorge Washington University

Washington, DC8 February 2006

1. Sheth SS. Missing female births in India. Lan-cet 2006;367:185–186.

2. Jha P, Kumar R, Vasa P, Dhingra N, Thiruchel-vam D, Moineddin R. Low male-to-female ratioof children born in India: national survey of 1.1million households. Lancet 2006;367:211–218.

3. Cheng TO. One child policy and increasedmechanization are additional risk factors forincreased coronary artery disease in modernChina. Int J Cardiol 2005;100:333.

4. Cheng TO. Medicine and health care along thesilk road. China’s population control programamong the national minorities. Arch InternMed 1985;145:137–138.

5. Cheng TO. China’s “missing” girls. Sciences1995;269:147–148.

doi:10.1016/j.amjcard.2006.02.029

Figure 1. Boys born per 100 girls in China during past 5 decades.

Figure 2. Progressive decline of boy/girl ratio in China from birth through toddler to elementary schoolage.

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