Parents will now be legally able to find out the sex of their unborn children before 32 weeks of pregnancy in South Korea.

The South Korean Constitutional Court on Wednesday found the restriction on revealing the sex of fetuses unconstitutional, nullifying the related law provision immediately.

The South Korean Medical Act Article 20 (2) stipulates doctors who reveal an immature fetus’ sex to anyone, including the mother, would have their license suspended face up to two years of imprisonment or 20 million won ($15,000) of fines.

The law was made in 1987 with concerns about sex-selective abortion based on the preference for sons.

Despite the punishment, the number of boys born to every 100 girls reached 116.5 in 1990. In the case of a third child, it reached 209.7 in 1993.

The birth gender ratio returned to the normal range, around 105 boys per 100 girls, in 2007.

All nine justices of the constitutional court agreed that the gender reveal ban violates the Constitution, while six supported an immediate nullification of the provision and three argued they should give National Assembly time to revise the law.

The six justices said the provision seemed to be ineffective in protecting babies' lives while excessively restricting parents’ right to know.

The other three including Chief Justice Lee Jong-seok said gender-selective abortion still remains and that it was not proper to abolish means to protect fetuses’ lives without creating alternatives.

They argued the level of restriction could be reduced by shortening the period of the gender notification ban from the current 32 weeks.