analysis that compares the difference in child sex ratios between Maharashtra and its neighboring states before and after the passage of the PNDT Act.

The key assumptions of this empirical strategy are that (a) Maharashtra and its neighboring states were on similar trajectories before 1988, i.e. they had parallel trends in child sex ratios before 1988; (b) couples in Maharashtra did not go to villages in neighboring states seeking sex selective abortions between 1988 and 1994 , i.e. there were no spillover effects; (c) the national ban did not affect enforcement in Maharashtra; and (d) the ban was similarly implemented in Maharashtra and its neighboring states.

The data for this study came from village and town level longitudinal data from the 1991 and 2001 Indian censuses. To account for spillover effects, the authors compare villages in Maharashtra to villages in neighboring states that are not located along the border of Maharashtra. This way, the newly treated villages are culturally similar to Maharashtrian villages but are geographically distant enough to prevent spillovers. The evaluation results suggest that after controlling for individual and community level factors, and spillover possibilities, there was a 14 to 26 percentage point increase in the female-to-male child sex ratio. The ban resulted in 106,000 more surviving girls in the 0-6 age groups in the newly treated rural areas.

While these results suggest that the ban was effective in achieving a less imbalanced sex ratio, caution must be used when interpreting them. First, the outcome variable in this study is the child sex ratio (which is affected by prenatal and postnatal sex discrimination), so the authors cannot isolate the effect of the ban on prenatal sex selection or SRB. Second, as the authors argue themselves, evidence on parallel trends in sex ratios before 1988 is not conclusive. Third, the available data do not allow the authors to test the assumption that the Maharashtra ban and the national ban were similarly implemented, or that the national ban did not affect enforcement in Maharashtra.

# _Republic of Korea_

In Korea, prenatal sex determination technology was introduced in the mid-1980s. Following the introduction of this technology, the country saw an increase in its SRB that continued until the mid-1990s. In response to the growing sex imbalances, the government enforced a ban on the use of prenatal sex identification in 1987. This ban, in combination with the restrictions on the use of abortion services, was expected to curb the practice of prenatal sex selection. In 1994, the government strengthened the provisions of the 1987 Act by imposing stricter penalties on medical professionals who broke the law. There is no specific information on how strong the enforcement of the ban was. Reports suggest that in 1990, the licenses of eight physicians were suspended on grounds that they had performed sex-determination tests. These arrests were widely reported in the media as well (Park & Cho 1995; Boer & Hudson 2017; Ganatra 2008).

Some observers claim that the momentary drop in SRB in 1991 could be attributed to the suspension of miscreant physicians in 1990. However, Park and Cho (1995) argue that this interpretation is flawed as it does not account for parents’ adherence to the Chinese lunar calendar. The year 1990 was the Year of the Horse (a zodiac sign deemed unfavorable for girls), so the greater number of girls registered in 1991 may have simply been 1990 female births that were registered a year later to ensure that the girls born could avoid the stigma of being born under the Horse sign. Further, they argue that the 1992 sex ratio lies between the rates of 1990 and 1991. In fact, SRB in Korea did not reach biologically normal levels until the late 2000s, i.e. nearly 20 years 20