Many of China's single-child parents choose to stay with their original families after marriage to share the burden of raising kids and carry on the family line for both sides, China Women's News reported.

In this type of marriage arrangement, which is dubbed "Liang tou hun", literally "marriage on two sides", a couple — both single children of their original families — stay under the same roof with the parents of either side alternatively.

Such a couple usually raises two children, one adopting the father's surname and mainly raised by his family, and the other given the mother's surname and raised by the mother's side.

This phenomenon has emerged in rural areas in East China's Zhejiang and Jiangsu provinces in recent years.

The new type of marriage is due to a fast-paced modern life, where young couples have no energy or time to take care of their kids and have to rely on their parents, said Yang Huili, a lawyer from Zhejiang Nuoliya Law Firm.

The dependence on original families is also a result of poor abilities for independent living of some single-child parents, Yang added.

There are, however, some advantages in this arrangement.

As a groom needn't give an expensive betrothal gift to the bride's family and the bride does not have to pay a dowry, it reduces the financial burden on both sides and stimulates more young people to get married, said Yang Hong, a lawyer from Zhejiang Siwei Law Firm.

She said the "two-sides marriage" helps alleviate the aging program facing Chinese society by encouraging couples to have two children.

She added with each of the two kids of the family adopting the surname of one of the parents, the new marriage arrangement could also prevent disputes in surname and child rearing.

Du Peng, a lawyer from Shunbo Law Firm of Zhejiang, said the "two-sides marriage" causes less mental pressure on a groom who otherwise has to live with the bride's family after marriage as his original family is less well-off, and thus has low willingness to take responsibility for the family.

In the "two-sides marriage", as the couple ties the knot with no financial burden, the relationship has less mental pressure on the man's side, Du said.

But there are also negative aspects.

While this new type of marriage can bring the bond between couples and their original families closer, the integrity of the nuclear family would be affected, and the couple's intimacy could be undermined, Yang Huili said.

In many cases, quarrels broke out between husbands and wives because of disputes over issues such as stay time allocated unevenly between the two sides.

For example, in one such family, Xiao Xi and her husband Xiao Zheng from Hangzhou, capital of Zhejiang, are both single children born after 1985.

Xiao Zheng refused to visit the tombs of his wife's family during Tomb-Sweeping Festival and viewed it a disgrace, as in the traditional patriarchal society it is the women's duty to pay a visit to tombs of the husband's family.

In addition, raising children separately causes problems such as a preference for one child over the other on one side.

"The bias would harm the relationship between the children and make it harder for them to integrate into the family," Yang said, "especially when the two kids of a couple live separately for a long time."

As for the prospects of the "two-sides' marriage", experts hold different opinions.

Yang Huili said the arrangement is the result of China's strict family planning policy. As restrictions on childbirth are loosened and couples are encouraged to have more than one child, the needs for such marriages will diminish and the phenomenon will gradually retreat.

With more professional domestic services becoming available, and improvements to the education system, particularly for preschool kids, young couples will find it easier to leave their original families, Yang Huili said.

On the other side, Yang Hong said the "two-sides marriage" will become more common. According to her, with improved education and social progress, people's attitudes toward marriage and surname adoption will become more open-minded, and the obsession with carrying on the family line will be weakened.