1 Valarie M. Hudson and Andrea M. den Boer, Bare Branches: The Security Implications of Asia’s Surplus Male Population; Cambridge, MA, The MIT Press, 2005, pp. 109-113, 171-172. See also, Mara Hvistendahl, Unnatural Selection: Choosing Boys over Girls, and the Consequences of a World Full of Men; Philadelphia, PA., Public Affairs (in the Perseus Books Group), 2011.
2 Bare Branches, pp. 112-113, 157.
3 Bare Branches, pp. 114-119.
4 Christophe Z. Guilmoto, Senior Fellow in Demography, Institut de Recherche pour le Developpement, Université Paris Descartes, personal communication.  These data, though not published, were collected with John Bongaarts when researching 12a below.
5 World Health Organization, 2015.
6 Nicholas D. Kristof and Sheryl WuDunn, Half the Sky: Turning Oppression into Opportunity for Women Worldwide; Vintage Books, 2010, pp. 109-122.
7 Bare Branches, p. 122. See also, Rita Banerji, items 9-10.
8  In India the number of dowry murders (bride burnings) is estimated at 8,000 per year, and in Pakistan, at about 2,000 per year.  See Rebecca Bundhun, Dowries and Death Continue Apace in India, The National, February 10, 2017, and Tehseen Saeed, Dowry Murder, The Tribune, March 2017. Bangladesh registered 4,500 dowry murders per year prior to 2014.  See UN Women Report 2014 – Annexes United Nations (May 2014), Table 6 page xiii, .
9 Juan Forero, Women in Latin America are Being Murdered at Record Rates, The Wall Street Journal, Dec. 19, 2018 and Reuters News, First Drugs, then oil, now Mexican cartels turn to human trafficking, April 29, 2020.
10 Graham Lee Brewer, The Crisis of Missing and Murdered Indigenous Women, High Country News, May 4 2018 and Carrie N. Baker and Katie Fleischer, Legislation to Address Missing and Murdered Indigenous Women Signed into Law, Oct. 12, 2020.
​11 Amartya Sen, “More Than 100 Million Women are Missing,” The New York Review of Books, December 20, 1990.
12 United Nations Population Fund, UNFPA State of the World Population 2020, p. 49.  Download the full report for complete information.  The report on the website is a summary.

12a John Bongaarts and Christophe Z. Guilmoto, “How Many More Missing Women? Excess Female Mortality and Prenatal Sex Selection, 1970–2050,” Population and Development Review 41(2): 241–269 (JUNE 2015), see chart p. 247, p. 258.  Access to this journal is limited to subscribers;  however, a copy of the paper can be viewed here.
​12b Christophe Z. Guilmoto, Senior Fellow in Demography, Institut de Recherche pour le Developpement, Université Paris Descartes, personal communication.  These data, though not published in this format, were collected with John Bongaarts when researching 12a above. Data for maternal deaths came from World Health Organization, 2015.
12c John Bongaarts and Christophe Z. Guilmoto, “How Many More Missing Women? Excess Female Mortality and Prenatal Sex Selection, 1970–2050,” Population and Development Review 41(2): 241–269 (JUNE 2015), see chart p. 247, p. 258.  Access to this journal is limited to subscribers;  however, a copy of the paper can be viewed here.  For global feminicide numbers, see the United Nations Office of Drugs and Crime, UNODC Global Study on Homicide, booklet 5.  Findings were announced in 2018 and published in 2019.
13 Christophe Guilmoto, Senior Fellow in Demography, Institut de Recherche pour le Developpement, Université Paris Descartes, personal communication. A review of methods, models, and assumptions used in these calculations is available at Klasen and Wink, Missing Women: A Review of the Debates and an Analysis of Recent Trends, 2002.
14 Nicholas Eberstadt and Evan Abramsky, “Has the ‘Global War against Baby Girls’ Come to America?” Institute for Family Studies, Jan. 27, 2020.  Grech Victor, “Further evidence of male offspring preference for certain subgroups in the United States (2007–2015),” Early Human Development, July 2017, Volume 110, pp. 9-12.  Authors note that son preference is observed in parents born overseas, but disappears in the next generation.
15 United Nations Population Fund, UNFPA, State of the World Population 2020, p. 51.
16 United Nations Population Fund, UNFPA, State of the World Population 2020, p. 51 for absolute numbers of missing women in China and India.  Data for total populations of China and India and for percentages of those populations that are female were found at data.worldbank.org.  Calculations were made from these data.

16a Rajineesh Kumar Yadav, Debt-free weddings prevent slavery in India, The Huffiington Post, Dec. 6, 2017.

17 Half the Sky, pp. xi-60 and Bare Branches, pp. 202-206, 214, 237, 241-243. Few studies have been done to document the link between sex trafficking and sex imbalance. Anti-trafficking activists report this link, and the annual US State Department Trafficking in Persons reports allege such a link, but data are thin. ​A study in India finds that for every (roughly) 1% increase in the sex ratio, there is a 0.635 increase in number of women trafficked. See Nishith Prakash and Krishna Chaitanya Vadlamannati, “Girls for Sale?  Child Sex Ratio and Girls Trafficking in India,” IZA Discussion Paper No. 8293, June 2014. (IZA – Forschungsinstitut zur Zukunft der Arbeit, Institute for the Study of Labor, Germany.
However, another study cautions that regions of the world with normal sex ratios (Latin America, Eastern Europe) have substantial trafficking problems, too, suggesting that multiple causes are in play. See Therese Hesketh and Zhu Wei Xing, “Abnormal sex ratios in human populations: Causes and consequences,” PNAS, Vol. 103 No. 36,  pp. 13271–13275, Sept. 5, 2006. More studies need to be done on this subject.
18 Regarding the correlation between distorted sex ratios and child marriage, see Bare Branches, pp. 204-205 and Unnatural Selection, pp. 190-191.
Researchers also report a correlation between distorted sex ratios and spousal age gap (the difference in age between husband and wife). See Reshmaan Hussam, “Marry Rich, Poor Girl: Investigating the Effects of Sex Selection on Intrahousehold Outcomes in India,” in Harvard Business School, Working Knowledge: Business Research for Business Leaders, 09 Oct 2017, Abstract, p. 22. Lena Edlund argues that sex selection expands the wealth gap between men and women in areas where it is practiced, privileging men over women. See “Son Preference, Sex Ratios, and Marriage Patterns,” Journal of Political Economy, 1999, vol. 107, no. 6, pt. 1, Abstract, p. 295.
Girl Up reports that maternal death rates for child mothers under the age of 15 are five times higher than for women in their early 20’s.
Maternal death used to be the leading cause of death worldwide for girls aged 15-19. However, in 2012 the World Health Organization reported that suicide has now displaced maternal death as the leading cause of death for teenage girls, particularly in South Asia and East Asia. See Nisha Lilia Diu, “Suicide is now the biggest killer of teenage girls worldwide: Here’s why,” The Telegraph, 25 May 2015.
19 Avraham Y. Ebenstein and Ethan Jennings Sharygin, “The Consequences of the “Missing Girls” of China,” The World Bank Economic Review, VOL. 23, No. 3, pp. 399-425, 2009, and Professor Li Shuzhuo, Director of the Institute for Population and Development Studies, Xi’an Jiaotong University, verbal communication, 2015.   Lastly, Nadia Diamond-Smith and Kara Rudolph find an increase in sex crimes,  domestic violence, and use of guns in regions with highly distorted sex ratios.  “The association between uneven sex ratios and violence:  Evidence from six Asian countries,” PLOS One (Public Library of Science), 2018.
 20 Bare Branches, pp. 203, 234-241, and Unnatural Selection, pp. 221-223.
21 Elizabeth Winkler, “China’s One-Child Policy May Be Making the Country More Violent: A 1 percent increase in the ratio between the sexes leads to a 5 percent increase in the Crime Rate,” New Republic, June 27, 2014. See also Lena Edlund, Hongbin Li, Junjian Yi, Junsen Zhang, “Sex Ratios and Crime: Evidence from China’s One-Child Policy,” in Review of Economics and Statistics, 2013, 95(5), 1520-1534. The latter study estimates that the sex ratio accounts for one seventh of the increase in crime in China.
21a Jean Dreze and Reetika Khera, “Crime, Gender, and Society in India: Insights from Homicide Data,” Population and Development Review, Vol. 26, No. 2 (June 2000), p. 342. Cited in Bare Branches, pp. 240-241.
22 Bare Branches, pp. 207-227.
23 Bare Branches, p. 259. Hudson and den Boer cite Christian G. Mesquida and Neil I. Wiener, “Human Collective Aggression: A Behavior Ecology Perspective,” Ethology and Sociobiology, Vol. 17, No. 4 (July 1996), pp. 247-262, and Laura Betzig, “Despotism and Differential Reproduction: A Cross-Cultural Correlation of Conflict Asymmetry, Hierarchy, and Degree of Polygyny,” Ethology and Sociobiology, Vol. 3, No. 4 (1982), pp. 209-221.

23a Valerie M. Hudson, Bonnie Ballif-Spanvill, Mary Caprioli, and Chad F. Emmett, Sex and World Peace, Columbia University Press, 2014.  The correlation between women’s rights and a country’s prosperity is a central tenet of the book.
24 Anna Fifield, “Two-husband strategy may be a solution for China’s one-child policy, professor posits,” The Washington Post, June 10, 2020.

24a Kunal Anand, “The real truth behind the crores of forced bachelors in India,” The India Times, June 14, 2017.

25 Unnatural Selection, pp. 225-229.
25a Mitali Nikore, Beti Bachao, Beti Padhao:  A Critical Review of Implementation,  The Times of India, Jan. 3, 2019. 
25b Aparna Kalra, “Modi’s (Shaky) Race to Save India’s Girls,” May 23, 2015 and “An Evaluation of Prime Minister Modi’s ‘Beti Padhao, Beti Bachao’ Initiative,” Centre for Development and Human Rights, February 19, 2016. 
26 United Nations Population Fund, UNFPA, State of the World Population 2020, p. 46.
28 Yuen Yeuk-laam “China census shows continuing gender imbalance, aging population,” Global Times Published, 21-1-2015
29 Christina Larson, “In China More Girls Are on the Way,” Bloomberg Business, July 31, 2014.

29a United Nations Population Fund, UNFPA State of the World Population 2020, p. 46.  Download the full report;  the information is not available in the summary on the website.
30 Klasen and Wink, Missing Women: A Review of the Debates and an Analysis of Recent Trends, 2002., pp. 2-3, pp. 14-15.
31 Christophe Guilmoto, “Sex Ratio Transition in Asia,” Population and Development Review 35(3): 519-549 (September 2009), pp. 524, 536.
32 Klasen and Wink, pp. 14-15. In developing countries plagued with malnutrition, a normal SRB is lower – closer to 104. Maternal malnutrition results in a disproportionately large number of male fetuses being either miscarried or stillborn, thus lowering the sex ratio at birth.
33 United Nations Development Program, see the Asia-Pacific Human Development Report called Power, Voice, and Rights: A Turning Point for Gender Equality in Asia and the Pacific, 2010, p. 42.
33a World Bank, Development Report on Gender Equality and Development, 2012.
34 Bare Branches, pp 249-254 and Unnatural Selection, pp. 225-229.