The demand for one-way permits is likely to fall substantially as more Hong Kong women have been marrying mainland men in recent years, says Secretary for Labour and Welfare Law Chi-kwong.

Given this reversing marriage trend, the city may see a reduction in its population sooner than the government's expectation of 2043, Law wrote on his blog.

A more accurate estimation, he added, can be made after the 2021 census.

Law said most cross-border marriages in the 1980s had Hong Kong men marrying mainland women, who mostly preferred settling in the SAR.

But in recent years, there is growing proportion of Hong Kong women tying the knot with mainland men and more of these families opt to live in the mainland.

In 2017, these couples accounted for 30 percent of the total registered cross-border marriages in Hong Kong.

Law predicted that the ratio between Hong Kong men and women marrying people from the mainland will reach 50:50 in 10 years' time.

He said this will likely lead to a reduction in the number of applications for one-way permits, under which mainlanders can apply for permission to move to Hong Kong permanently, usually for family reunion purposes.

A quota of 150 such permits, issued by mainland authorities, are available each day.

James Mak Yiu-pong, principal matching consultant of Matching Loves, was not surprised by the reversing trend. He said some in the matchmaking industry are actually doing business mainly by linking Hong Kong women and mainland men.

He said the reason behind the trend is that Hong Kong men are losing the advantages they previously had.

Mak said Hong Kong men in general earned more than their mainland counterparts and their financial capabilities allowed them to marry and support their mainland wives in the past. However, the situation is reversing gradually as China's economy develops.

Some big firms in the innovative industry, especially IT giants such as Tencent and Huawei, are offering higher salaries than many jobs in Hong Kong, Mak said.

"Comparing a mainland man and a Hong Kong man who both earn HK$60,000, the mainland man can afford a better quality of life in the mainland," he added.

As women usually expect their husbands to earn more, those in Hong Kong have started to rely on wealthy mainland men in recent years, Mak said.

He added that local men usually have a wider international perspective, but well-educated mainland men are catching up in this aspect too.

Law, meanwhile, said blended families - those that consist of a couple, the children they have together, and their children from previous relationships - have also become a trend. In 2017, 25 percent of the newly registered couples were entering their second marriage.

cindymt.wan@singtaonewscorp.com