More than a quarter of Korean couples aged between 25 and 39 were childless in 2022, a study showed Monday, with a substantial increase in the ratio of DINK -- double income, no kids -- couples among young South Koreans.

The Korea Labor Institute report analyzed the trend of young married couples, particularly related to households with the head of the family aged between 25 and 39. The study showed that the percentage of couples without kids in the 25-39 age group came to 27.1 percent, up almost 5 percentage points from 22.2 percent in 2013.

Most of the increase was attributed to the rising number of DINK couples, who in 2013 took up 21 percent of this particular demographic. The figure jumped up to 36.3 percent in 2022.

In contrast, only 13.5 percent of the young one-income couples were childless in 2022, marking a relatively moderate increase compared to 12.3 percent in 2013.

The report showed that 71 percent of the women in couples that had no children were in the labor force in 2022, compared to 40.6 percent of the women in couples that had children.

"Our findings show that (women) in many couples give up financial activities due to difficulties of doing both their job and raising children," the report said.

But while childless couples tended to work more, the report also found that they were less likely to own their own home. About 34.6 percent of childless couples owned homes, compared to 52 percent of the couples that did have children.

The researchers noted the rising price of housing is likely one of the main factors in the low fertility rate among young couples, adding that this may be why Seoul -- the priciest city in the country to live in -- had one of the highest percentages of young childless couples at 45.2 percent in 2022.