Preliminary data by Statistics Korea, on Monday, revealed that the portion of male births of the total newborns in South Korea declined to a record low in 2020.
The information came amid the latest sign that traditional preference for male children had waned as the ratio of baby boys to every 100 newborn girls came to 104.9 in 2020, down from 105.5 in 2019.
The tally marked the lowest number since the statistics agency began compiling related data in 1990.
When natural births are calculated with no preference for baby boys, the birth sex ratio reached between 103 and 107, according to the agency.
In South Korea, men have outnumbered women due to its traditional preference for male children. However, since hitting 116.5 in 1990, the birth sex ratio had seen a steady decline.
The agency earlier forecast the number of women in South Korea would begin to outpace that of men in 2029.
South Korea is grappling with demographic challenges from its chronic low birth-rate and rapid aging.
The country reported the first natural decline in population in 2020, as the number of deaths outpaced that of newborns.