Jeddah, Saudi Arabia  - The departure lounge at Riyadh's airport was quiet. People waiting for the early flight to Ha'il were sleepy. They watched two seated boys of primary school age, one of whom was speaking gibberish and incessantly wiggling his legs.

The other boy, a little older, had a slightly crooked back. Next to them sat their father, in a bodyshirt as traditionally worn by Saudi men, with both of his black-cloaked wives, the boys' mothers.

The boys were born before 2004, when the Saudi government introduced compulsory premarital blood tests mainly aimed at reducing the number of children with inherited diseases. Relatives in the ultraconservative Islamic kingdom still marry each other despite the known health risks to their offspring.

There are three premarital screening centres in the Red Sea city of Jeddah. Couples who have applied for a marriage licence are required to visit a centre together. Since the prospective bride and groom are forbidden from being alone together before marriage, the couple is usually accompanied by a male member of the woman's family.

"If the doctor determines that one of the two carries an inherited disease, we inform the couple, who can then do whatever they want," said Dr Shadia Matbouli, a physician at King Abdulaziz University Hospital in Jeddah.

Saudi couples are not prohibited from marrying if they have been rated "high-risk," nor do Saudis marry without intending to start a family. The concept of a childless marriage based on love is socially unacceptable in Saudi Arabia, where having five or more children is normal.

Initial results of the premarital screening programme, which has included tests for AIDS and hepatitis since 2008, are rather sobering. According to a study published in 2007, of 488,315 individuals tested, 2,375 couples were rated "high-risk." A total of 89.6 per cent of these couples went ahead and got married anyway.

Common genetic blood disorders in Saudi Arabia include sickle cell disease and thalassemia. Of the individuals tested, 4.20 per cent had sickle cell trait, 0.26 per cent had sickle cell disease, 3.22 per cent had thalassemia trait, and 0.07 per cent had thalassemia disease.

"People were sceptical at first and many baulked at the screening. But now it's fairly well accepted since a lot of families with generations of consanguineous marriages among their kin have suffered greatly from these diseases," Matbouli remarked.

She added that intermarriage between cousins was less common in Jeddah, a port city that has attracted immigrants and travellers for centuries, than in places like Al-Hufuf and Al-Hassa.

Al-Jawhara al-Sherif, a young Saudi woman who works in Jeddah for an international company that makes paper towels and likes getting together in coffeehouses with girlfriends in the evening, is all for the screening programme -- and not only because it can reduce the risk of conceiving children with inherited diseases.

She said it also protected women from the double standard practiced by many Saudi men. Premarital sex in Saudi Arabia is illegal, and women generally obey the law. Men, however, often do not, particularly on trips abroad, where they can have sex with casual acquaintances or prostitutes.

"The tests prevent a man infected abroad with HIV (the virus that causes AIDS) or other sexually transmitted diseases from passing them on to his Saudi wife," al-Sherif said.

A recently published study said that premarital screening had detected 49 HIV infections in 10 months. As a precaution against infection shortly before a wedding, test results are recognized for six months only. So postponing a wedding can mean having to retake the tests.

In addition, men must be screened prior to each of their marriages. The divorce rate is relatively high in Saudi Arabia, and a man may have up to four wives at a time if he is able to support them, according to Sharia, or Islamic law.

Among those passing through the screening programme have been numerous girls between eight and 12 years of age offered as brides to older men by their fathers. In these cases, too, if the people involved are determined to marry despite all warnings and counseling, the doctors are powerless to stop them. (dpa)