the sex ratio which is common to all the survey rounds, independently of the cohort of birth of the child, and not specific to a particular period.<sup>21</sup> The most recent survey (NFHS-III) also shows an increasing sex ratio at birth starting from the end of the 1980s onward, which corresponds to the timing of the diffusion of ultrasound technologies (also consistent with the sex ratio in the Indian Census). Figure 3 shows that the decreasing trend is specific to first births, while the sex ratio for higher-order births is somewhat stable throughout the whole survey period and significantly higher than that for first births in 1980 and after. This is further indicative of the use of sex selective abortion, known to be much more common among higher order births. Indeed, pooled NFHS data on parental gender preferences indicate that, albeit more than one third of ever-married women want to have more sons than daughters (compared to only 2.5 percent who want more daughters than sons), more than 80 percent of them want _at least_ one daughter and about 86 percent want _at least_ one son.<sup>22</sup> Moreover, 42 (14.5) percent desire at least two sons (daughters).

Table 1 reports summary statistics for the pooled sample of ever-married women aged 15–49 by the sex of their first-born (refer to the data appendix for a description and availability of these variables in the NFHSs).<sup>23</sup> Panel (a) reports socio-demographic and fertility-related variables. Most characteristics differ significantly between the sample of women with a first-born girl and a first-born boy. In particular, the table shows that women with first-born girls are significantly more likely to be educated, to have married and had their first child later in life, to have (and desire to have) more children, to use contraception (and have undergone permanent sterilization)<sup>24</sup> , to have performed a prenatal ultrasound test, and to have had a shorter spacing between the first 21Rosenblum (2013) uses the 2002-2004 Reproductive and Child Health Survey (RCH-II) and finds a similar pattern: higher sex ratios for births occurred in the past, especially for lower birth orders. He tests for the exogeneity of the sex of the first born, discusses potential recall or survival bias in the data (without attempting to test or disentangle the two), and argues that the extent of the bias is small.

> 22These figures are based on the NFHS question about the number of children women would like to have if they could go back to the time before they started childbearing. NFHS-III indicates that average ideal family size among ever-married women is 2.5 children (down from 2.9 in NFHS-I). Interviewed women were also asked the ideal sex composition for these children: in NFHS-I they indicated 1.6 sons, 1.1 daughters, and 0.2 of either sex, while in NFHS-III 1.2 sons, 0.9 daughters, and 0.4 of either sex.

23All the estimates shown in this paper have been computed using sample weights provided by the NFHS. Given that three surveys were conducted in different years, the sample weights used in the pooled sample have been multiplied by the fraction of the total female population aged 15–49 in India (obtained from the United Nations Population Division World Population Prospects: 2012 Revision, _http_ : _//esa.un.org/wpp/Excel − Data/population.htm_ ) and the number of women aged 15-49 interviewed in each survey round.

> 24Knowledge of contraception is nearly universal among ever-married Indian women in NFHS-III: 99.2% of women know one or more methods of contraception and current use is 55% (up from 98.9% and 45.3% in NFHS-II, respectively). Female sterilization, with a prevalence of 37%, is a permanent contraception method (to _limit_ the number of births) that accounts for 67.4% of all contraceptives used. The highest adoption rate of female sterilization, is among women with three children who have two sons. The most common _spacing_ methods are condoms and the rhythm method, each used by 5% of women (NFHS-III data).

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