DAMASCUS - Ibrahim Issa, a jovial Syrian taxi-driver who wears a blue robe over an ample belly, has nine children from two wives. He plans to marry a third wife soon.

He says it is up to Allah whether more children arrive, and not for him to interfere, say, by using contraception. Like all Damascus taxi-drivers, he complains about the cost of living and how hard it is to make ends meet on the $300 a month he earns.

Issa, 43, shrugs when asked if all those mouths to feed don't make life harder for him. No, I'm delighted, he grins.

Syria now has a population of 20 million people, with a growth rate that remains one of the world's highest at about 2.4 percent. But it has declined since averaging 3.2 percent from 1947-94, according to the Syrian Commission for Family Affairs.

We have a population problem, no question, said Nabil Sukkar, a Syrian economist formerly with the World Bank. Unless we cope with it, it could be a burden on our development.

He said labour supply was growing about 4.5 percent a year, due to rapid population expansion in earlier decades, outpacing the capacity of Syria's economy to create jobs for the quarter of a million youngsters arriving on the job market every year.

Too big a population means a high burden on government services, such as education, electricity and health care, he said. Perhaps in 20 years the growth rate will go down to 1.5 percent as in Egypt, but in the meantime we do have a problem.

The official unemployment rate is around 10 percent, but independent estimates put it at anywhere up to 25 percent.

DISPARATE FERTILITY RATES

Syrian women have an average of 3.6 children each, but this masks big disparities between cities and the countryside.

Despite the efforts of men like Issa the taxi-driver, fertility rates in Damascus and three other governorates are set to fall from 2 to 2.5 children per woman now to 1.4 to 2 by 2025, below the replacement rate of 2.1 children per woman.

In the seven least-developed of Syria's 14 governorates, women have between 3.8 and 6.2 children. Their fertility rates are not expected to decline much in the next 15 years.

Demographers say urbanisation and the spread of education, especially among girls and women, are among the most potent forces that eventually curb population growth across the world.

Syria's minority Christians, who tend to be well-educated citydwellers with high aspirations, provide a good example.

My grandfather had eight children, my father had four and I have only two, said Samer Lahham, who runs ecumenical affairs at the Greek Orthodox Patriarchate in the Syrian capital.

Now maybe after five years each family will have only one because of economic problems, education costs, living costs.

Religion as such is irrelevant, said Lebanese demographer Riad Tabbarah. Development brings education, which is a crucial factor because it increases the cost of raising children. Once education and modernisation set in, fertility falls.

Syria, only now emerging from a socialist-style command economy, has modernised more slowly than nearby Lebanon, where fertility is already below the replacement rate and where the Lebanese have long yearned for lifestyles beyond their means.

What affects fertility is also the difference between your income and your conventional standard, Tabbarah said.

Contact with the outside world often gives people a taste for cars or other goods they can only afford by having fewer children, he said. In Syria, that exposure came slowly and they still have a high fertility level, but it's coming down.

COMMUNICATION REVOLUTION

The aspirations of Syrians, like Arabs elsewhere, are now rising because of satellite TV, mobile phones and the Internet. Young citizens are likely to have greater expectations than their parents, with readier access to regional and international media, a Western diplomat said. Even remote villages have satellite dishes. Many Syrians work abroad and return.

Youngsters may be delaying marriage in places like Damascus, partly because they spend years in higher education and partly because they then cannot meet the traditional marriage costs.

A 32-year-old philosophy graduate said he was still single and lived with his parents because he could not afford the apartment that any bride would demand, even though he drives a taxi to supplement what he makes working at a government clinic.

There are so many like me, said the frustrated young man, refusing to be named. It's enough to drive people to crime.

In rural areas, families are often large because it is relatively cheap to raise children until they are nine or 10 and can start working in the fields or earning money elsewhere.

Until modernisation prompts people who lack knowledge or access to contraceptives to desire fewer children, family planning advice is likely to fall on deaf ears. Before that, nobody wants it. After that, nobody needs it, Tabbarah said.

Giving girls a chance to go to school is a vital element in tackling Syria's population challenges, said Etab Altaqee at the U.N. Population Fund, which works with the Syrian government.

Altaqee said some community-level efforts in the northeast had yielded small but encouraging results.

In one of the poorest villages, the girls were saying we want to continue our education, but we need a bus because our fathers won't allow us to go to school by ourselves, she said. It was as easy as that, just to provide them with transport. (Editing by Samia Nakhoul)