The United Nations warned that failure to pass a controversial birth control law in the Philippines could reverse gains in development goals amid stiff opposition from the powerful Catholic Church.
The bill seeks to make it mandatory for the government to provide free contraceptives in a country where more than 80 percent of the population is Catholic and which has one of the highest maternal mortality rates in Southeast Asia.
Ugochi Daniels, country representative from the UN Population Fund, said on Sunday she remained "cautiously optimistic" that President Benigno Aquino's allies who dominate the House of Representatives could muster the numbers to pass the bill on Tuesday after 14 years of often divisive debate.
"What is important now is to highlight the urgency of the bill," Daniels said.
The UN, in a separate statement, said the Philippines was unlikely to achieve its millennium development goal of reducing maternal deaths by three quarters and providing universal access to reproductive health by 2015.
The body said it had "extensively studied" the proposed law which once passed could "vastly improve health and quality of life" in a country where a third of the population live on less than a dollar a day.
A rise in unwanted pregnancies could swell the number of people in poverty, and lead to an explosion in urban slum populations, the UN said.
And while the country has been enjoying economic expansion of more than five percent in recent years, the gains could be reversed, it warned.
"Hopes of future prosperity could turn to dust if the country is not able to deal with the population growth," the UN said.
Daniels said maternal deaths would continue to rise with more and more women getting pregnant at a young age without the proper health care and access to key reproductive information.
Between 2006 and 2010, the maternal mortality rate rose 36 percent to 221 deaths per 100,000 live births, from 162 deaths per 100,000 live births in 2000 to 2005, according to the government's 2011 Family Health Survey.
And many of those giving birth were girls between 15 and 19 years old, the UN said.
"I think we've gone from 11 (maternal deaths) a day to between 14 and 15 a day now. And unfortunately, most of these are poor women," Daniels said.
The UN Population Fund was "very concerned" about the rising number of deaths, she said, noting that even in war-torn Afghanistan the trend was downwards.
She urged Philippine lawmakers to quickly pass the bill and "stop failing our young".
"This is now the time. We have been waiting for a very long time," Daniels said.
The UN's call came as Catholic priests and nuns led thousands in a protest rally in Manila Saturday to urge lawmakers to scrap the bill.
Besides free contraception, it would also give the poor preferential access to family planning services in state hospitals, while lessons on family planning and sex education would become compulsory in schools and for couples applying for a marriage licence.
The UN has said a lack of education and access to condoms has led to an explosion of HIV infections in the Philippines, which it said is now one of seven countries in the world where cases have risen by 25 percent or more since 2001.
Aquino has signalled his backing for the bill ahead of Tuesday's vote in the House of Representatives.
The Senate, the upper house of parliament, also needs to pass the bill before it can become law, but some of its leaders were seen giving their support to the church rally Saturday.