Lito Atienza has no doubt about his views. The mayor of Manila - a devout Catholic - seems to punch the air with his words as he explains why he has banned the city's public clinics from distributing free contraceptives. "I consider artificial contraception to be a very very destructive practice which ruins Filipino values," he says. "Value of life, value of the family, value of relationship."

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Mayor Atienza's policy has brought him into direct conflict with the Philippine government, which sees population control as vital to the national's development. While the two sides clash, the number of Filipinos grows inexorably and there are signs that the country is increasingly unable to cope.

The Philippines has one of the fastest population growth rates in Asia, with the total doubling in the last 30 years to around 80 million and set to double again in the next 30.

Chuck Lerman of the U.S. Agency for International Development says that could cause economic stagnation and severe strains on the environment. He says many Filipino women want smaller families - surveys show that on average they want to have one fewer child over a lifetime.

Kids here soon learn to look after their siblings

That would certainly help many of the families living in Baseco. This squatter camp clinging to the seawall of Manila Port is home to 50,000 people, three-quarters of them under the age of 18. Children swarm around you when you arrive, appearing from every corner of the shanty town.

Maria, a mother in Baseco, says she loves her five children - but she would have preferred to have had only four so she could have provided better for them. "I really want to give them a good education, to be able to go to school," she says.

Maria is now using an IUD supplied by the Women's Health Foundation, a non-governmental organisation which runs a busy clinic in Baseco.

Gladys Malayang in her clinic

Gladys Malayang, the foundation's executive director, says there is heavy demand for family planning services - but there is a problem. The foundation cannot obtain the free contraceptives to which it is entitled from the City of Manila, because of the mayor's policy.

The national government admits there is little it can do to solve the problem. Delivery of health services has been devolved to local authorities. Tomas Osias, head of the government's Population Commission, says he cannot force local politicians to carry out the national family planning programme but that he hopes to achieve 'consensus' with opponents like Mayor Atienza.

Dr. Margarita Go-Singco Holmes: government policy is hurting the poor

Others are not so calm. "For me this beggars belief," says Dr. Margarita Go-Singco Holmes, the country's best-known sex therapist. She argues that well-off women can easily afford to buy their own contraceptives, so the policy of the mayor - and other local politicians who think similarly - only affects the poor.

One chance of compromise between the two sides lies in science. Thanks to research by institutions like Georgetown University in the US, there have been dramatic advances in the reliability of natural family planning, which relies on periodic abstinence.

Esperanza Dowling - trying to reconcile Catholic values and Filipino needs

Esperanza Dowling of the Philippine Federation for Natural Family Planning is promoting the use of the "mucus method," which is now used by around 400,000 couples in the country. They are encouraged by simple visual aids such as coloured bracelets which remind husband and wife where they are in the woman's reproductive cycle.

But Esperanza Dowling admits that this is not the answer for everybody. Indeed, her organisation split away from the Catholic church because the federation believes natural family planning should be an alternative rather than a replacement for artificial contraception.

Family planning campaigns offer a brighter future - but wil the message get through?

Like many other women's activists, she says the issue is fundamentally about the right to choose. "It has to be women who make the decision," as Gladys Malayang puts it. "If women are able to make good decisions and are supported by the government then they'll be to make good decisions for the whole country."

Also in this edition of Crossing Continents, Julian Pettifer explores Filipino hoop dreams and investigates a disturbing wave of killings on university campuses.