With the number of unmarried women in Saudi Arabia rising at alarming rates, an undeclared marriage system known locally as misyar is gaining prominence.

Saudi women walk outside a shopping mall in Riyadh.

This form of marriage has also generated controversy and subsequent debate at all levels of the society and among religious scholars.

Misyar is described as a form of marriage in which the wife gives up her rights offered under the religion, including the right to have the husband living with her in the same house and providing her with necessary expenses.

In short the woman gives up the right to have an independent home. The husband may come to see her at her parent's home at whatever time he chooses for himself, or at a time agreed by the two.

Although there are no official statistics on this kind of marriage, most social researchers agree the phenomenon is on the rise and is no longer confined to a particular group.

Some scholars approve of the practice by saying that it meets the basic requirements of legal marriage under Islam and helps in solving many social problems resulting from spinsterhood.

Others denounce the practice, saying it is unlawful because it does not meet the marriage requirements as stipulated by Shariah, and could thus result in more serious moral and social problems.

Among those who approve misyar is prominent Saudi scholar Shaikh Abdullah Bin Sulaiman Bin Menie. A member of the Supreme Ulema Council, Shaikh Menie says misyar is legal since it meets the requirements for a lawful marriage under Islam.

"What distinguishes this kind of marriage from others is that the wife voluntarily waives her right of having the husband living with her in the same house and paying for her necessary expenses. She agrees to have the husband visit her at any time, day or night, at the time convenient to him," he said.

Shaikh Menie said the conditions agreed by the wife do not affect the validity of the marriage and the wife can still demand her full rights, including having the husband live with her and provide for her expenses. The husband in this case is free to agree to her terms or opt for divorce, he added.

He cited the case of Al Sayida Souda, one of the wives of Prophet Mohammad (Peace Be Upon Him), who agreed to give up her right of having the Prophet spend every alternate night with her in favour of the Prophet's other wife, Al Sayida Aisha.

The problem of spinsterhood prompted the Shura Council to intervene.

It recently asked 50 Saudi female intellectuals and educationists to present strategies for dealing with the issue.

Saudi families, women in particular, were advised to accept a more modest dowry to lessen marriage expenses.

The director of social affairs department in Jeddah, Ehsan Al Tayeb described misyar as a "social phenomenon resulting from discrepancies in the country's very family structure and the marriage system".

Legal advisor, Hamid Fallata, says of misyar: "It is the choice of the coward who resort to marrying secretly," and warned the practice could result in more serious social and legal problems instead of solving these.

Social researcher, Abdullah Al Dosari, cited several reasons for the phenomenon.

"Some of these relate to men, others to women and still others have to do with the society in general. Some men want to have more than one wife for various reasons, perhaps for not being happy with the first wife."

"Women fear spinsterhood and find solace in this kind of marriage. Divorced and widowed women would not want to spend the rest of their life without a husband," he explained.

Matchmaker Um Talal said some women resort to misyar because they want to stay at their parents' home to take care of them, especially if there is no one else in the family to do so.

Some physically challenged women would also want to marry this way and their parents would not object because they want their daughter to have a husband.