Table 1.

Descriptive summary of background characteristics of mixed-sex twins, including tests for significant difference between the first-birth cohort and the two subsequent cohorts

	Pooled	Born Before 1995	Born in 1995–2005	Born After 2005
	(1)	(2)	(3)	(4)
Mortality (1–59 months)	0.09	0.17	0.07	0.05
Female	0.50	0.50	0.50	0.50
Birth Year	2000	1986	2000	2011
Birth Order	3.26	3.68	3.18	2.98
Rural	0.68	0.69	0.66	0.68
Northern Region	0.60	0.61	0.58	0.60
Hindu	0.79	0.77	0.80	0.79
Poorest 40%	0.40	0.36	0.38	0.46
Mother No School	0.45	0.58	0.44	0.33
Mother Primary School	0.16	0.20	0.17	0.12
Mother Secondary School	0.30	0.19	0.32	0.39
Mother Tertiary	0.09	0.04	0.07	0.16
Mother Age at Birth	25.32	24.68	24.92	26.34
Total Children Born to Mother	4.32	5.22	4.19	3.69
Mother’s Ideal Number of Boys	1.36	1.56	1.31	1.26
Mother’s Ideal Number of Girls	1.08	1.14	1.07	1.05
Mother’s Ideal Sex Ratio	0.55	0.57	0.55	0.54
N	6,200	1,868	2,278	2,054

Notes: All estimates use pooled data from the Indian National Family Health Survey (1992–1993, 1998–1999, 2005–2006, 2015–2016) and use sampling weights provided by the NFHS. All measures are dichotomous except birth year (ranges from 1958 to 2016), birth order (ranges from 1 to 11), mother age at birth (ranges from 12 to 47), total number of children born (ranges from 2 to 13), mother’s ideal number of boys (ranges from 0 to 7), mother’s ideal number of girls (ranges from 0 to 6), and ideal sex ratio (ranges from 0 to 1 and excludes women who desire 0 children). Bold numbers indicate a statistically significant (p < .05) difference between the birth cohort in question and the first birth cohort (i.e., born before 1995). Two-sample t tests are performed for all continuous outcomes, and chi-square tests are performed for all dichotomous outcomes.