Table 1. Socioeconomic characteristics of 96 Indian surrogates and of Indian women aged 20–34 years old in the general population.

		Indian surrogates (N = 96)		General population of Indian women aged 20–34 (N = 60,852)	P-value of permutation test(1)
		n/N	%	%
Age	(years)
	20–24	12/93	13	37	<0.001
	25–29	41/93	44	34	<0.05
	≥30 (2)	40/93	43	29	<0.01
Indian region
	Northern	14/96	15	37	<0.001
	Western	58/96	60	32	<0.001
	Southern	15/96	16	13	0.48
	Eastern	9/96	9	18	<0.001
Married living with husband		81/96	84	85	0.87
Number of children
	None	0/95	0	20	NA(3)
	1–2	73/95	77	44	<0.001
	3–4	21/95	22	27	0.25
	5	1/95	1	9	<0.001
First cild at age ≤ 20		33/39	85	48	<0.001
At least 2ndary education (4)		51/91	56	39	<0.01
Family income ≥ extreme poverty line (1.25 USD)		56/66	85	58	<0.001
Family income ≥ poverty line (2 USD)		47/66	71	24	<0.001
Employed (5)		55/95	58	42	<0.01
Hindu religion		60/85	71	82	0.02

(1) Permutation tests compared percentages observed among surrogates and in national data for one category. Tests were done with the R function “Permutation Tests for Nonparametric Statistics” (perm.test, version 1.4, package: jmuOutlier) developed by Steven T. Garren.

(2) Age was divided into 5-year groups in order to be comparable with national data. Regarding guidelines for surrogacy, 82 surrogates were aged 21–35 years old, 1 surrogate was aged 20 years and 9 were aged 36–45 (of whom only 2 women were aged 40 years or above).

(3) NA: Not applicable, as no surrogate had 0 children

(4) At least 7 or 8 years of education (secondary, graduate and post-graduate).

(5) Women employed before surrogacy. In the national data, women employed at some point in the 12 months preceding the survey.